Android学习笔记总结

第一步：

Android(1) - 在 Windows 下搭建 Android 开发环境，以及 Hello World 程序

搭建 Android 的开发环境，以及写一个简单的示例程序

· 在 Windows 下搭建 Android 开发环境

· Android 项目的目录结构说明

· 写一个简单的 Hello World 程序

一、在 Windows 下搭建 Android 开发环境 1、安装 JDK (Java Development Kit) http://download.java.net/jdk6/ 2、安装 Android SDK http://developer.android.com/sdk 3、安装 Eclipse http://www.eclipse.org/ 4、打开 Eclipse ，并安装其 Android 插件（ADT）打开菜单 "Help" -> "Install New Software"，在 "Availabe Software" 中加入地址 http://dl-ssl.google.com/android/eclipse/ ，然后安装 ADT(Android Development Tools) 5、新建 Android 项目 "New" -> Android Project，Project Name - 项目名称；Build Target - 编译项目的 SDK 版本；Application name - 程序名称；Package name - 包名；Min SDK Version - 程序所支持的最低 SDK 版本代号（2 对应 1.1，3 对应 1.5，4 对应 1.6） 6、运行 Android 项目打开菜单 "Run" -> "Run Configurations" -> New launch configuration，设置启动项目名称，在 Android 选项卡中选择启动项目，在 Target 选项卡中设置模拟器 7、创建/使用模拟 SD 卡创建 SD 卡，运行类似如下命令：mksdcard -l sdcard 512M d:\android\sdcard.img 模拟器中使用 SD 卡，在项目配置的 Target 选项卡的 "Additional Emulator Command Line Options" 框中输入类似如下参数：-sdcard d:\android\sdcard.img 8、配置模拟器运行类似如下命令：android create avd --name android15 --target 2。或者直接在菜单 "Window" -> "Android AVD Manager" 中配置模拟器 9、浏览模拟 SD 卡中的内容调试程序，在 DDMS 中选择 "File Explorer" ，在其中的 sdcard 目录下就是模拟 SD 卡中的内容 10、查看日志 LogCat Window -> Show View -> Other -> Android -> LogCat 11、在模拟器中安装/卸载 apk 安装 apk 运行类似如下命令：adb install name.apk；卸载 apk 运行类似如下命令：adb uninstall packagename（注：这里的参数是需要卸载的包名） 12、反编译 Android 程序解压 apk 文件，取出其中的 classes.dex 文件，运行类似如下命令：dexdump.exe -d classes.dex > dump.txt（其意思是将 classes.dex dump 出来，并将反编译后的代码保存到指定的文本文件中） 13、人品不好是出现的某些错误的解决办法如果出现类似如下的错误等 no classfiles specified Conversion to Dalvik format failed with error 1 解决办法：Project -> Clean 出现 Android SDK Content Loader 60% （一直卡在 60%）解决办法：Project -> 去掉 Build Automatically 前面的勾 14、查看 SDK 源代码先想办法搞到源代码，如这个地址 http://www.digginmobile.com/android.asp ，然后将其解压到 SDK 根路径下的 sources 文件夹内即可二、Android 项目的目录结构 1、src - 用于放置源程序 2、gen - 自动生成 R.java 文件，用于引用资源文件（即 res 目录下的数据） 3、assets - 用于放置原始文件，Android 不会对此目录下的文件做任何处理，这是其与 res 目录不同的地方 4、res/drawable - 用于放置图片之类的资源；res/layout - 用于放置布局用的 xml 文件；res/values - 用于放置一些常量数据 5、AndroidManifest.xml - Android 程序的清单文件，相当于配置文件，配置应用程序名称、图标、Activity、Service、Receiver等三、Hello World 程序 1、res/layout/main.xml

代码

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" android:id="@+id/layout" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/txt" /> </LinearLayout>

2、res/values/strings.xml

代码

<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">layout 直接调用 values 中的字符串</string> <string name="hello2">编程方式调用 values 中的字符串</string> <string name="app_name">webabcd_hello</string> </resources>

3、res/drawable 目录下放置一个名为 icon.png 的图片文件 4、AndroidManifest.xml

代码

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.webabcd.hello" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".Main" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> <uses-sdk android:minSdkVersion="3" /> </manifest>

5、Main.java

代码

package com.webabcd.hello; import android.app.Activity; import android.os.Bundle; import android.widget.LinearLayout; import android.widget.TextView; public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // 将指定的布局文件作为 Activity 所显示的内容 setContentView(R.layout.main); // 动态地在指定的容器控件上添加新的控件 TextView txt = new TextView(this); txt.setText("动态添加控件"); // setContentView(txt); ((LinearLayout)this.findViewById(R.id.layout)).addView(txt); // 引用资源文件内的内容作为输出内容 TextView txt1 = (TextView)this.findViewById(R.id.txt); txt1.setText(this.getString(R.string.hello2)); } }

Android(2) - 布局(Layout)和菜单(Menu)

介绍在 Android 中各种布局的应用，以及菜单效果的实现

· 各种布局方式的应用，FrameLayout, LinearLayout, TableLayout, AbsoluteLayout, RelativeLayout

· 为指定元素配置上下文菜单，为应用程序配置选项菜单，以及多级菜单的实现

1、各种布局方式的演示 res/layout/main.xml

代码

列1"列2"列3"列1" /> </TableRow> </TableLayout>  <AbsoluteLayout android:layout_height="wrap_content" android:layout_width="fill_parent"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="AbsoluteLayout" android:layout_x="100px" android:layout_y="100px" /> </AbsoluteLayout>  <RelativeLayout android:id="@+id/RelativeLayout01" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="wrap_content" android:id="@+id/abc" android:layout_height="wrap_content" android:text="centerInParent=true" android:layout_centerInParent="true" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="marginLeft=20px" android:layout_marginLeft="20px" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="xxx" android:layout_below="@id/abc" android:layout_alignRight="@id/abc" /> </RelativeLayout> </LinearLayout>

res/values/strings.xml

<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello">Hello Layout</string> <string name="app_name">webabcd_layout</string> </resources>

Main.java

代码

package com.webabcd.layout; import android.app.Activity; import android.os.Bundle; public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); } }

2、上下文菜单，选项菜单，子菜单 res/layout/main.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/txt1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello_contextMenu" /> <TextView android:id="@+id/txt2" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello_subMenu" /> </LinearLayout>

res/values/strings.xml

代码

<?xml version="1.0" encoding="utf-8"?> <resources> <string name="hello_contextMenu">Hello Context Menu</string> <string name="hello_subMenu">Hello Context Sub Menu</string> <string name="app_name">webabcd_menu</string> </resources>

Main.java

代码

package com.webabcd.menu; import android.app.Activity; import android.os.Bundle; import android.view.ContextMenu; import android.view.Menu; import android.view.MenuItem; import android.view.SubMenu; import android.view.View; import android.view.ContextMenu.ContextMenuInfo; import android.widget.TextView; import android.widget.Toast; // 演示两种菜单的实现方式：上下文菜单（通过在某元素上长按，来呼出菜单）和选项菜单（通过按手机上的菜单按钮，来呼出菜单） public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // 为 R.id.txt1 注册一个上下文菜单（在此 TextView 上长按，则会呼出上下文菜单） // 具体呼出的菜单内容需要重写 onCreateContextMenu 来创建 TextView txt1 = (TextView) this.findViewById(R.id.txt1); this.registerForContextMenu(txt1); // 为 R.id.txt2 注册一个上下文菜单 TextView txt2 = (TextView) this.findViewById(R.id.txt2); this.registerForContextMenu(txt2); } // 重写 onCreateContextMenu 用以创建上下文菜单 // 重写 onContextItemSelected 用以响应上下文菜单 @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { super.onCreateContextMenu(menu, v, menuInfo); // 创建 R.id.txt1 的上下文菜单 if (v == (TextView) this.findViewById(R.id.txt1)) { // ContextMenu.setIcon() - 设置菜单的图标 // ContextMenu.setHeaderTitle() - 设置菜单的标题 menu.setHeaderIcon(R.drawable.icon01); menu.setHeaderTitle("我是菜单"); // 用 ContextMenu.add() 来增加菜单项，返回值为 MenuItem // 第一个参数：组ID // 第二个参数：菜单项ID // 第三个参数：顺序号 // 第四个参数：菜单项上显示的内容 menu.add(1, 0, 0, "菜单1"); // MenuItem - 新增菜单项后的返回类型，针对菜单项的其他设置在此对象上操作 menu.add(1, 1, 1, "菜单2").setCheckable(true); } // 创建 R.id.txt2 的上下文菜单（多级上下文菜单） else if (v == (TextView) this.findViewById(R.id.txt2)) { // ContextMenu.addSubMenu("菜单名称") - 用来添加子菜单。子菜单其实就是一个特殊的菜单 SubMenu sub = menu.addSubMenu("父菜单1"); sub.setIcon(R.drawable.icon01); sub.add(0, 0, 0, "菜单1"); sub.add(0, 1, 1, "菜单2"); sub.setGroupCheckable(1, true, true); SubMenu sub2 = menu.addSubMenu("父菜单2"); sub2.setIcon(R.drawable.icon01); sub2.add(1, 0, 0, "菜单3"); sub2.add(1, 1, 1, "菜单4"); sub2.setGroupCheckable(1, true, false); } } // 重写 onCreateOptionsMenu 用以创建选项菜单 @Override public boolean onCreateOptionsMenu(Menu menu) { MenuItem menuItem = menu.add(0, 0, 0, "菜单111111111111111111111"); // MenuItem.setIcon() - 设置菜单项的图标 // MenuItem.setTitleCondensed() - 菜单的简标题，如果指定了简标题的话，菜单项上的标题将会以此简标题为准 // MenuItem.setAlphabeticShortcut() - 设置选中此菜单项的快捷键 // 注：菜单项超过 6 个的话，第 6 个菜单将会变为 More 菜单，多余的菜单会在单击 More 菜单之后显示出来 menuItem.setIcon(R.drawable.icon01); menuItem.setTitleCondensed("菜单1"); menuItem.setAlphabeticShortcut('a'); menu.add(0, 1, 1, "菜单2").setIcon(R.drawable.icon02); menu.add(0, 2, 2, "菜单3").setIcon(R.drawable.icon03); menu.add(0, 3, 3, "菜单4"); menu.add(0, 4, 4, "菜单5"); menu.add(0, 5, 5, "菜单6"); menu.add(0, 6, 6, "菜单7").setIcon(R.drawable.icon04); menu.add(0, 7, 7, "菜单8").setIcon(R.drawable.icon05); return true; } // 重写 onOptionsItemSelected 用以响应选项菜单 @Override public boolean onOptionsItemSelected(MenuItem item) { super.onOptionsItemSelected(item); Toast.makeText(Main.this, "被单击的菜单项为：" + String.valueOf(item.getItemId()), Toast.LENGTH_SHORT).show(); return false; } }

Android(3) - 对话框(Dialog)和通知(Notification)

介绍在 Android 中种对话框及各种通知效果的应用

· 常用对话框的使用，弹出式对话框、日期选择对话框、时间选择对话框、进度条对话框

· 通知（出现在通知列表）和提示性通知（Toast）的演示

1、常用对话框的演示 res/layout/main.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/txtMsg" android:layout_width="wrap_content" android:layout_height="wrap_content"></TextView> <Button android:id="@+id/btn1" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn2" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn3" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn4" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn5" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn6" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> </LinearLayout>

res/layout/view.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:text="我是一个 View" android:layout_width="wrap_content" android:layout_height="wrap_content"> </TextView> </LinearLayout>

res/values/array.xml

<?xml version="1.0" encoding="utf-8"?> <resources>  <string-array name="ary"> <item>项目 1</item> <item>项目 2</item> </string-array> </resources>

Main.java

代码

package com.webabcd.dialog; import java.util.Calendar; import android.app.Activity; import android.app.AlertDialog; import android.app.DatePickerDialog; import android.app.Dialog; import android.app.ProgressDialog; import android.app.TimePickerDialog; import android.app.DatePickerDialog.OnDateSetListener; import android.app.TimePickerDialog.OnTimeSetListener; import android.content.DialogInterface; import android.content.DialogInterface.OnClickListener; import android.os.Bundle; import android.view.View; import android.widget.DatePicker; import android.widget.TextView; import android.widget.TimePicker; import android.widget.Button; public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // 弹出式对话框的 Demo。先调用 Builder()，在 Create()，需要显示对话框的是后再调用 show() AlertDialog dialog = new AlertDialog.Builder(this).setTitle("弹出对话框").create(); dialog.show(); // 以下是各种对话框的 Demo MyButtonClickListener listener = new MyButtonClickListener(); Button btn1 = (Button) this.findViewById(R.id.btn1); btn1.setText("简单的对话框的 Demo"); btn1.setOnClickListener(listener); Button btn2 = (Button) this.findViewById(R.id.btn2); btn2.setText("包括常用设置的对话框(数据来自 xml)"); btn2.setOnClickListener(listener); Button btn3 = (Button) this.findViewById(R.id.btn3); btn3.setText("弹出的对话框的内容是一个 View"); btn3.setOnClickListener(listener); Button btn4 = (Button) this.findViewById(R.id.btn4); btn4.setText("日期选择对话框"); btn4.setOnClickListener(listener); Button btn5 = (Button) this.findViewById(R.id.btn5); btn5.setText("时间选择对话框"); btn5.setOnClickListener(listener); Button btn6 = (Button) this.findViewById(R.id.btn6); btn6.setText("进度条对话框"); btn6.setOnClickListener(listener); } class MyButtonClickListener implements View.OnClickListener { @Override public void onClick(View v) { // 具体的对话框的实现可以通过重写 onCreateDialog 完成 switch (v.getId()) { case R.id.btn1: Main.this.showDialog(0); break; case R.id.btn2: Main.this.showDialog(1); break; case R.id.btn3: Main.this.showDialog(2); break; case R.id.btn4: Main.this.showDialog(3); break; case R.id.btn5: Main.this.showDialog(4); break; case R.id.btn6: Main.this.showDialog(5); break; } } } @Override public Dialog onCreateDialog(int id) { switch (id) { case 0: // 一个简单的弹出对话框 return new AlertDialog.Builder(this).setTitle("这是一个简单的弹出对话框的 Demo") .create(); case 1: // 一个相对复杂的弹出对话框 return new AlertDialog.Builder(this) .setTitle("标题") // 设置标题 // .setCustomTitle(View) // 以一个 View 作为标题 .setIcon(R.drawable.icon01) // 设置标题图片 // .setMessage("信息") // 需要显示的弹出内容 .setPositiveButton("确定", new OnClickListener() { // 设置弹框的确认按钮所显示的文本，以及单击按钮后的响应行为 @Override public void onClick(DialogInterface a0, int a1) { TextView txtMsg = (TextView) Main.this.findViewById(R.id.txtMsg); txtMsg.append("单击了对话框上的“确认”按钮\n"); } }) .setItems(R.array.ary, new DialogInterface.OnClickListener() { // 弹框所显示的内容来自一个数组。数组中的数据会一行一行地依次排列 public void onClick(DialogInterface dialog, int which) { } }) // 其他常用方法如下 // .setMultiChoiceItems(arg0, arg1, arg2) // .setSingleChoiceItems(arg0, arg1, arg2) // .setNeutralButton(arg0, arg1) // .setNegativeButton(arg0, arg1) .create(); case 2: // 弹出对话框为指定的 View 的 Demo return new AlertDialog.Builder(this).setTitle("此对话框的内容是一个 View") .setView(this.findViewById(R.layout.view)).create(); case 3: // 弹出日期选择对话框 Calendar c = Calendar.getInstance(); return new DatePickerDialog(this, new OnDateSetListener() { @Override public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) { TextView txtMsg = (TextView) Main.this.findViewById(R.id.txtMsg); txtMsg.append("新设置的日期为：" + String.valueOf(year) + "-" + String.valueOf(monthOfYear) + "-" + String.valueOf(dayOfMonth) + "\n"); } }, c.get(Calendar.YEAR), c.get(Calendar.MONTH), c.get(Calendar.DATE)); case 4: // 弹出时间选择对话框 Calendar c2 = Calendar.getInstance(); return new TimePickerDialog(this, new OnTimeSetListener() { @Override public void onTimeSet(TimePicker view, int hourOfDay, int minute) { TextView txtMsg = (TextView) Main.this.findViewById(R.id.txtMsg); txtMsg.append("新设置的时间为：" + String.valueOf(hourOfDay) + ":" + String.valueOf(minute) + "\n"); } }, c2.get(Calendar.HOUR), c2.get(Calendar.MINUTE), true); case 5: // 弹出进度条对话框 ProgressDialog progress = new ProgressDialog(this); progress.setMessage("loading..."); return progress; default: return null; } }}

2、各种提示效果的演示 res/layout/main.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <Button android:id="@+id/btn1" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn2" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn3" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> <Button android:id="@+id/btn4" android:layout_width="wrap_content" android:layout_height="wrap_content"></Button> </LinearLayout>

res/layout/view.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/txtMsg" android:layout_width="wrap_content" android:layout_height="wrap_content"> </TextView> </LinearLayout>

Main.java

代码

package com.webabcd.notification; import android.app.Activity; import android.app.Notification; import android.app.NotificationManager; import android.app.PendingIntent; import android.content.Context; import android.content.Intent; import android.os.Bundle; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // 通过 Tost.makeText().show() 来实现提示性的通知效果 // 短时间的提示性通知的 Demo Button btn1 = (Button) this.findViewById(R.id.btn1); btn1.setText("短时间提示"); btn1.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { Toast.makeText(Main.this, "我是短时间提示", Toast.LENGTH_SHORT).show(); } }); // 长时间的提示性通知的 Demo Button btn2 = (Button) this.findViewById(R.id.btn2); btn2.setText("长时间提示"); btn2.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { Toast.makeText(Main.this, "我是长时间提示", Toast.LENGTH_LONG).show(); } }); // 以一个 View 作为提示性通知的 Demo Button btn3 = (Button) this.findViewById(R.id.btn3); btn3.setText("以一个 View 做提示"); btn3.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { View view = inflateView(R.layout.view); TextView txtMsg = (TextView) view.findViewById(R.id.txtMsg); txtMsg.setText("提示内容"); Toast toast = new Toast(Main.this); toast.setView(view); toast.setDuration(Toast.LENGTH_LONG); toast.show(); } }); Button btn4 = (Button) this.findViewById(R.id.btn4); btn4.setText("发出一个通知（Notification）"); btn4.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { // 实例化通知管理器 NotificationManager nm = (NotificationManager) getSystemService(NOTIFICATION_SERVICE); // 指定单击通知后所打开的详细的通知页面（单击通知后打开 NotificationView） PendingIntent contentIntent = PendingIntent.getActivity( Main.this, 0, new Intent(Main.this, NotificationView.class), 0); // 实例化一个通知，并指定其图标和标题（在提示栏上显示） Notification n = new Notification(R.drawable.icon01, "我是滚动的通知信息我是滚动的通知信息我是滚动的通知信息", System.currentTimeMillis()); // 设置通知的发送人和通知的详细内容（打开提示栏后在通知列表中显示） n.setLatestEventInfo(Main.this, "通知发送人", "我是详细的通知信息我是详细的通知信息我是详细的通知信息", contentIntent); // 100 毫秒延迟后，震动 250 毫秒，暂停 100 毫秒后，再震动 500 毫秒 n.vibrate = new long[] { 100, 250, 100, 500 }; // 发出通知（其中第一个参数为通知标识符） nm.notify(0, n); } }); } // 将指定的 xml 资源转换为一个 View private View inflateView(int resource) { LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE); return vi.inflate(resource, null); } // 打开详细通知页后此 Activity 会被 Pause，从详细通知页返回后此 Activity 会被 Resume @Override protected void onPause() { // TODO Auto-generated method stub super.onPause(); Log.d("MyDebug", "onPause"); } @Override protected void onResume() { // TODO Auto-generated method stub super.onResume(); Log.d("MyDebug", "onResume"); } }

NotificationView.java

代码

package com.webabcd.notification; import android.app.Activity; import android.app.NotificationManager; import android.os.Bundle; import android.widget.TextView; // 单击通知列表的某个通知后，所打开的详细的通知页 public class NotificationView extends Activity { protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.view); TextView txtMsg = (TextView)this.findViewById(R.id.txtMsg); txtMsg.setText("点通知之后所链接到的 Activity"); NotificationManager nm = (NotificationManager) getSystemService(NOTIFICATION_SERVICE); // 取消显示在通知列表中的指定通知（参数为通知标识符） nm.cancel(0); // 需要关闭此 Activity 的话就 finish 它既可 // this.finish(); } }

Android(4) - 活动(Activity), 服务(Service), 广播(Broadcast), 广播接收器(BroadcastReceiver)

介绍

在 Android 中使用 Activity, Service, Broadcast, BroadcastReceiver

活动(Activity) - 用于表现功能

服务(Service) - 相当于后台运行的 Activity

广播(Broadcast) - 用于发送广播

广播接收器(BroadcastReceiver) - 用于接收广播

Intent - 用于连接以上各个组件，并在其间传递消息

1、演示 Activity 的基本用法，一个 Activity 启动另一个 Activity，启动另一个 Activity 时为其传递参数，被启动的 Activity 返回参数给启动者的 Activity

Main.java

代码

package com.webabcd.activity;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

public class Main extends Activity {

TextView txt;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

this.setContentView(R.layout.main);

txt = (TextView) this.findViewById(R.id.txt);

txt.setText("Activity 1");

Button btn = (Button) this.findViewById(R.id.btn);

btn.setText("启动另一个Activity");

btn.setOnClickListener(new Button.OnClickListener() {

@Override

public void onClick(View v) {

// 实例化 Intent，指定需要启动的 Activity

Intent intent = new Intent();

intent.setClass(Main.this, MyActivity.class);

// 实例化 Bundle，设置需要传递的参数

Bundle bundle = new Bundle();

bundle.putString("name", "webabcd");

bundle.putDouble("salary", 100.13);

// 将需要传递的参数赋值给 Intent 对象

intent.putExtras(bundle);

// startActivity(intent); // 启动指定的 Intent（不等待返回结果）

// Main.this.finish();

// 启动指定的 Intent，并等待返回结果

// 其中第二个参数如果大于等于零，则返回结果时会回调 onActivityResult() 方法

startActivityForResult(intent, 0);

}

});

Log.d("MyDebug", "onCreate");

}

// 被启动的 Activity 返回结果时的回调函数

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent data) {

if (resultCode == Activity.RESULT_OK){

Bundle bundle = data.getExtras();

String name = bundle.getString("name");

double salary = bundle.getDouble("salary");

txt.setText("Activity 1" + "\n名字：" + name + "\n薪水：" + String.valueOf(salary));

}

@Override

protected void onStart() {

// TODO Auto-generated method stub

super.onStart();

Log.d("MyDebug", "onStart");

}

@Override

protected void onStop() {

// TODO Auto-generated method stub

super.onStop();

Log.d("MyDebug", "onStop");

}

@Override

protected void onRestart() {

// TODO Auto-generated method stub

super.onRestart();

Log.d("MyDebug", "onRestart");

}

@Override

protected void onPause() {

// TODO Auto-generated method stub

super.onPause();

Log.d("MyDebug", "onPause");

}

@Override

protected void onResume() {

// TODO Auto-generated method stub

super.onResume();

Log.d("MyDebug", "onResume");

}

@Override

protected void onDestroy() {

// TODO Auto-generated method stub

super.onDestroy();

Log.d("MyDebug", "onDestroy");

}

MyActivity.java

代码

package com.webabcd.activity;

import android.app.Activity;

import android.content.Intent;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

import android.widget.TextView;

// 被另一个 Activity 所启动的 Activity

public class MyActivity extends Activity {

Intent intent;

/** Called when the activity is first created. */

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

this.setContentView(R.layout.main2);

// 获取启动者传递过来的参数

intent = this.getIntent();

Bundle bundle = intent.getExtras();

String name = bundle.getString("name");

double salary = bundle.getDouble("salary");

TextView txt = (TextView) this.findViewById(R.id.txt);

txt.setText("Activity 2" + "\n名字：" + name + "\n薪水：" + String.valueOf(salary));

Button btn = (Button) this.findViewById(R.id.btn);

btn.setText("返回前一个Activity");

btn.setOnClickListener(new Button.OnClickListener() {

public void onClick(View v) {

// 返回参数给启动者

MyActivity.this.setResult(Activity.RESULT_OK, intent);

MyActivity.this.finish();

}

});

}

AndroidManifest.xml

代码

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="com.webabcd.activity" android:versionCode="1"

android:versionName="1.0">

<intent-filter>

</intent-filter>

</activity>

<!--

如果有需要用到的 Activity ，则都要在这里做相应的配置

-->

</application>

<uses-sdk android:minSdkVersion="3" />

</manifest>

2、Service, Broadcast, BroadcastReceiver 的演示

Main.java

代码

package com.webabcd.service;

import android.app.Activity;

import android.content.BroadcastReceiver;

import android.content.ComponentName;

import android.content.Context;

import android.content.Intent;

import android.content.IntentFilter;

import android.content.ServiceConnection;

import android.os.Bundle;

import android.os.IBinder;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.TextView;

* startService() 和 bindService() 的区别

* startService() - 正常理解就好

* bindService() - 使当前上下文对象（本例中就是 Activity）通过一个 ServiceConnection 对象邦定到指定的 Service 。这样，如果上下文对象销毁了的话，那么其对应的 Service 也会被销毁

public class Main extends Activity implements OnClickListener {

private TextView txtMsg;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

setTitle("android 之 service");

this.findViewById(R.id.btnStart).setOnClickListener(this);

this.findViewById(R.id.btnStop).setOnClickListener(this);

this.findViewById(R.id.btnBind).setOnClickListener(this);

this.findViewById(R.id.btnUnbind).setOnClickListener(this);

txtMsg = (TextView)this.findViewById(R.id.txtMsg);

// 实例化自定义的 BroadcastReceiver

receiver = new UpdateReceiver();

IntentFilter filter = new IntentFilter();

// 为 BroadcastReceiver 指定 action ，使之用于接收同 action 的广播

filter.addAction("com.webabcd.service.msg");

// 以编程方式注册 BroadcastReceiver 。配置方式注册 BroadcastReceiver 的例子见 AndroidManifest.xml 文件

// 一般在 OnStart 时注册，在 OnStop 时取消注册

this.registerReceiver(receiver, filter);

// this.unregisterReceiver(receiver);

}

@Override

public void onClick(View v) {

Intent intent = new Intent(Main.this, MyService.class);

switch (v.getId()) {

case R.id.btnStart:

this.startService(intent);

break;

case R.id.btnStop:

this.stopService(intent);

break;

case R.id.btnBind:

this.bindService(intent, conn, Context.BIND_AUTO_CREATE);

break;

case R.id.btnUnbind:

this.unbindService(conn);

break;

}

// bindService() 所需的 ServiceConnection 对象

private ServiceConnection conn = new ServiceConnection() {

@Override

public void onServiceConnected(ComponentName className, IBinder service) {

}

@Override

public void onServiceDisconnected(ComponentName className) {

}

};

private String msg="";

private UpdateReceiver receiver;

// 实现一个 BroadcastReceiver，用于接收指定的 Broadcast

public class UpdateReceiver extends BroadcastReceiver{

@Override

public void onReceive(Context context, Intent intent) {

msg = intent.getStringExtra("msg");

txtMsg.append(msg + "\n");

}

MyService.java

代码

package com.webabcd.service;

import android.app.Service;

import android.content.Intent;

import android.os.IBinder;

import android.util.Log;

// 演示 Service 的生命周期。具体信息运行程序后在 LogCat 中查看

public class MyService extends Service {

@Override

public IBinder onBind(Intent intent) {

Log.d("MyDebug", "onBind");

sendMsg("onBind");

// TODO Auto-generated method stub

return null;

}

@Override

public void onCreate() {

// TODO Auto-generated method stub

super.onCreate();

Log.d("MyDebug", "onCreate");

sendMsg("onCreate");

}

@Override

public void onDestroy() {

// TODO Auto-generated method stub

super.onDestroy();

Log.d("MyDebug", "onDestroy");

sendMsg("onDestroy");

}

@Override

public void onRebind(Intent intent) {

// TODO Auto-generated method stub

super.onRebind(intent);

Log.d("MyDebug", "onRebind");

sendMsg("onRebind");

}

@Override

public void onStart(Intent intent, int startId) {

super.onStart(intent, startId);

Log.d("MyDebug", "onStart");

sendMsg("onStart");

}

@Override

public boolean onUnbind(Intent intent) {

Log.d("MyDebug", "onUnbind");

sendMsg("onUnbind");

// TODO Auto-generated method stub

return super.onUnbind(intent);

}

// 发送广播信息

private void sendMsg(String msg){

// 指定广播目标的 action （注：指定了此 action 的 receiver 会接收此广播）

Intent intent = new Intent("com.webabcd.service.msg");

// 需要传递的参数

intent.putExtra("msg", msg);

// 发送广播

this.sendBroadcast(intent);

}

MyBootReceiver.java

代码

package com.webabcd.service;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.util.Log;

public class MyBootReceiver extends BroadcastReceiver {

// 用于接收满足条件的 Broadcast（相应的 Broadcast 的注册信息详见 AndroidManifest.xml ，当系统启动完毕后会调用这个广播接收器）

@Override

public void onReceive(Context arg0, Intent arg1) {

Log.d("MyDebug", "onReceive");

// 启动服务

Intent service = new Intent(arg0, MyService.class);

arg0.startService(service);

}

AndroidManifest.xml

代码

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="com.webabcd.service" android:versionCode="1"

android:versionName="1.0">

<intent-filter>

</intent-filter>

</activity>

<!--

如果有需要用到的 service ，则都要在这里做相应的配置

-->

<!--

注册一个 BroadcastReceiver

其 intent-filter 为 android.intent.action.BOOT_COMPLETED（用于接收系统启动完毕的 Broadcast）

-->

<intent-filter>

</intent-filter>

</receiver>

</application>

<!--

接受系统启动完毕的 Broadcast 的权限

-->

<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

<uses-sdk android:minSdkVersion="3" />

</manifest>

Android(5) - 控件(View)之TextView, Button, ImageButton, ImageView, CheckBox, RadioButton, AnalogClock, DigitalClock

介绍在 Android 中使用各种控件(View)

· TextView - 文本显示控件

· Button - 按钮控件

· ImageButton - 图片按钮控件

· ImageView - 图片显示控件

· CheckBox - 复选框控件

· RadioButton - 单选框控件

· AnalogClock - 钟表（带表盘的那种）控件

· DigitalClock - 电子表控件

1、TextView 的 Demo textview.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">  <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" /> </LinearLayout>

_TextView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.TextView; public class _TextView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.textview); // 设置 Activity 的标题 setTitle("TextView"); TextView txt = (TextView) this.findViewById(R.id.textView); // 设置文本显示控件的文本内容，需要换行的话就用“\n” txt.setText("我是 TextView\n显示文字用的"); } }

2、Button 的 Demo button.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <Button android:id="@+id/button" android:layout_width="wrap_content" android:layout_height="wrap_content"> </Button> </LinearLayout>

_Button.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; public class _Button extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.button); setTitle("Button"); Button btn = (Button) this.findViewById(R.id.button); btn.setText("click me"); // setOnClickListener() - 响应按钮的鼠标单击事件 btn.setOnClickListener(new Button.OnClickListener(){ @Override public void onClick(View v) { TextView txt = (TextView) _Button.this.findViewById(R.id.textView); txt.setText("按钮被单击了"); } }); } }

3、ImageButton 的 Demo imagebutton.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <ImageButton android:id="@+id/imageButton" android:layout_width="wrap_content" android:layout_height="wrap_content"> </ImageButton> </LinearLayout>

_ImageButton.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.ImageButton; import android.widget.TextView; public class _ImageButton extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.imagebutton); setTitle("ImageButton"); ImageButton imgButton = (ImageButton) this.findViewById(R.id.imageButton); // 设置图片按钮的背景 imgButton.setBackgroundResource(R.drawable.icon01); // setOnClickListener() - 响应图片按钮的鼠标单击事件 imgButton.setOnClickListener(new Button.OnClickListener(){ @Override public void onClick(View v) { TextView txt = (TextView) _ImageButton.this.findViewById(R.id.textView); txt.setText("图片按钮被单击了"); } }); } }

4、ImageView 的 Demo imageview.xml

代码

_ImageView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.ImageView; public class _ImageView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.imageview); setTitle("ImageView"); ImageView imgView = (ImageView) this.findViewById(R.id.imageView); // 指定需要显示的图片 imgView.setBackgroundResource(R.drawable.icon01); } }

5、CheckBox 的 Demo checkbox.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <CheckBox android:text="CheckBox01" android:id="@+id/chk1" android:layout_width="wrap_content" android:layout_height="wrap_content"></CheckBox> <CheckBox android:text="CheckBox02" android:id="@+id/chk2" android:layout_width="wrap_content" android:layout_height="wrap_content"></CheckBox> <CheckBox android:text="CheckBox03" android:id="@+id/chk3" android:layout_width="wrap_content" android:layout_height="wrap_content"></CheckBox> </LinearLayout>

_CheckBox.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.CheckBox; import android.widget.CompoundButton; import android.widget.TextView; public class _CheckBox extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.checkbox); setTitle("CheckBox"); CheckBox chk = (CheckBox) this.findViewById(R.id.chk1); // setOnCheckedChangeListener() - 响应复选框的选中状态改变事件 chk.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { TextView txt = (TextView) _CheckBox.this.findViewById(R.id.textView); txt.setText("CheckBox01 的选中状态：" + String.valueOf(isChecked)); } }); } }

6、RadioButton 的 Demo radiobutton.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <RadioGroup android:id="@+id/radioGroup" android:layout_width="fill_parent" android:layout_height="fill_parent" android:checkedButton="@+id/rad3" android:orientation="horizontal" android:gravity="center_vertical|center_horizontal"> <RadioButton android:text="rad1" android:id="@+id/rad1" android:layout_width="wrap_content" android:layout_height="wrap_content"></RadioButton> <RadioButton android:text="rad2" android:id="@+id/rad2" android:layout_width="wrap_content" android:layout_height="wrap_content"></RadioButton> <RadioButton android:text="rad3" android:id="@+id/rad3" android:layout_width="wrap_content" android:layout_height="wrap_content"></RadioButton> </RadioGroup> </LinearLayout>

_RadioButton.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.RadioButton; import android.widget.RadioGroup; import android.widget.TextView; public class _RadioButton extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.radiobutton); setTitle("RadioButton"); RadioGroup group = (RadioGroup) this.findViewById(R.id.radioGroup); // setOnCheckedChangeListener() - 响应单选框组内的选中项发生变化时的事件 group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() { @Override public void onCheckedChanged(RadioGroup group, int checkedId) { TextView txt = (TextView) _RadioButton.this.findViewById(R.id.textView); txt.setText(((RadioButton)findViewById(checkedId)).getText() + " 被选中"); } }); } }

7、AnalogClock 的 Demo analogclock.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">  <AnalogClock android:id="@+id/analogClock" android:layout_width="wrap_content" android:layout_height="wrap_content"> </AnalogClock> </LinearLayout>

_AnalogClock.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; public class _AnalogClock extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.analogclcok); setTitle("AnalogClock"); } }

8、DigitalClock 的 Demo digitalclock.xml

代码

_DigitalClock.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; public class _DigitalClock extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.digitalclcok); setTitle("DigitalClcok"); } }

Android(6) - 控件(View)之DatePicker, TimePicker, ToggleButton, EditText, ProgressBar, SeekBar, AutoCompleteTextView, MultiAutoCompleteTextView

介绍在 Android 中使用各种控件(View)

· DatePicker - 日期选择控件

· TimePicker - 时间选择控件

· ToggleButton - 双状态按钮控件

· EditText - 可编辑文本控件

· ProgressBar - 进度条控件

· SeekBar - 可拖动的进度条控件

· AutoCompleteTextView - 支持自动完成功能的可编辑文本控件

· MultiAutoCompleteTextView - 支持自动完成功能的可编辑文本控件，允许输入多值（多值之间会自动地用指定的分隔符分开）

1、DatePicker 的 Demo datepicker.xml

代码

_DatePicker.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; public class _DatePicker extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.datepicker); // 具体的应用可参见对话框中的示例 setTitle("DatePicker"); } }

2、TimePicker 的 Demo timepicker.xml

代码

_TimePicker.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; public class _TimePicker extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.timepicker); // 具体的应用可参见对话框中的示例 setTitle("TimePicker"); } }

3、ToggleButton 的 Demo togglebutton.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <ToggleButton android:id="@+id/toggleButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textOn="关闭" android:textOff="打开" /> </LinearLayout>

_ToggleButton.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; import android.widget.ToggleButton; public class _ToggleButton extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.togglebutton); setTitle("ToggleButton"); final ToggleButton btn = (ToggleButton) this.findViewById(R.id.toggleButton); // setOnClickListener() - 响应按钮的鼠标单击事件 btn.setOnClickListener(new Button.OnClickListener(){ @Override public void onClick(View v) { TextView txt = (TextView) _ToggleButton.this.findViewById(R.id.textView); // ToggleButton.isChecked() - 双状态按钮的按钮状态 txt.setText("按钮状态：" + String.valueOf(btn.isChecked())); } }); } }

4、EditText 的 Demo edittext.xml

代码

_EditText.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.EditText; public class _EditText extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.edittext); setTitle("EditText"); EditText txt = (EditText) this.findViewById(R.id.editText); txt.setText("我可编辑"); } }

5、ProgressBar 的 Demo progressbar.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">   <ProgressBar android:id="@+android:id/progress_large" style="?android:attr/progressBarStyleLarge" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <ProgressBar android:id="@+android:id/progress" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <ProgressBar android:id="@+android:id/progress_small" style="?android:attr/progressBarStyleSmall" android:layout_width="wrap_content" android:layout_height="wrap_content" />  <ProgressBar android:id="@+id/progress_horizontal" style="?android:attr/progressBarStyleHorizontal" android:layout_width="200px" android:layout_height="wrap_content" android:max="100" android:progress="50" android:secondaryProgress="75" /> </LinearLayout>

_ProgressBar.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.Window; // 另见对话框中的进度条 public class _ProgressBar extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); // 设置特性以允许在应用程序的标题栏上显示进度条（条状） requestWindowFeature(Window.FEATURE_PROGRESS); // 设置特性以允许在应用程序的标题栏上显示进度条（圆圈状） requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); this.setContentView(R.layout.progressbar); setTitle("ProgressBar"); // 在标题栏上显示进度条（条状） setProgressBarVisibility(true); // 在标题栏上显示进度条（圆圈状） setProgressBarIndeterminateVisibility(true); // 指定进度条的进度 setProgress(50 * 100); setSecondaryProgress(75 * 100); } }

6、SeekBar 的 Demo seekbar.xml

代码

_SeekBar.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.SeekBar; import android.widget.TextView; public class _SeekBar extends Activity implements SeekBar.OnSeekBarChangeListener { SeekBar mSeekBar; TextView mProgressText; TextView mTrackingText; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.seekbar); setTitle("SeekBar"); mSeekBar = (SeekBar) findViewById(R.id.seekBar); // setOnSeekBarChangeListener() - 响应拖动进度条事件 mSeekBar.setOnSeekBarChangeListener(this); mProgressText = (TextView) findViewById(R.id.progress); mTrackingText = (TextView) findViewById(R.id.tracking); } // 拖动进度条后，进度发生改变时的回调事件 public void onProgressChanged(SeekBar seekBar, int progress, boolean fromTouch) { mProgressText.setText(progress + "%"); } // 拖动进度条前开始跟踪触摸 public void onStartTrackingTouch(SeekBar seekBar) { mTrackingText.setText("开始跟踪触摸"); } // 拖动进度条后停止跟踪触摸 public void onStopTrackingTouch(SeekBar seekBar) { mTrackingText.setText("停止跟踪触摸"); } }

7、AutoCompleteTextView 的 Demo autocompletetextview.xml

代码

_AutoCompleteTextView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.ArrayAdapter; import android.widget.AutoCompleteTextView; public class _AutoCompleteTextView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.autocompletetextview); setTitle("AutoCompleteTextView"); // 实例化适配器，指定显示格式及数据源 ArrayAdapter<String> adapter = new ArrayAdapter<String>( this, android.R.layout.simple_dropdown_item_1line, ary); AutoCompleteTextView textView = (AutoCompleteTextView) findViewById(R.id.editText); // 指定自动完成控件的适配器 textView.setAdapter(adapter); } // 自动完成控件的所需数据的数据源 private String[] ary = new String[] { "abc", "abcd", "abcde", "abcdef", "abcdefg", "hij", "hijk", "hijkl", "hijklm", "hijklmn", }; }

8、MultiAutoCompleteTextView 的 Demo multiautocompletetextview.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">  <MultiAutoCompleteTextView android:id="@+id/editText" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>

_MultiAutoCompleteTextView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.ArrayAdapter; import android.widget.MultiAutoCompleteTextView; public class _MultiAutoCompleteTextView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.multiautocompletetextview); setTitle("MultiAutoCompleteTextView"); // 实例化适配器，指定显示格式及数据源 ArrayAdapter<String> adapter = new ArrayAdapter<String>( this, android.R.layout.simple_dropdown_item_1line, ary); MultiAutoCompleteTextView textView = (MultiAutoCompleteTextView) findViewById(R.id.editText); textView.setAdapter(adapter); // 设置多个值之间的分隔符，此处为逗号 textView.setTokenizer(new MultiAutoCompleteTextView.CommaTokenizer()); } // 自动完成控件的所需数据的数据源 private String[] ary = new String[] { "abc", "abcd", "abcde", "abcdef", "abcdefg", "hij", "hijk", "hijkl", "hijklm", "hijklmn", }; }

Android(7) - 控件(View)之ZoomControls, Include, VideoView, WebView, RatingBar, Tab, Spinner, Chronometer, ScrollView

介绍在 Android 中使用各种控件(View)

· ZoomControls - 放大/缩小按钮控件

· Include - 整合控件

· VideoView - 视频播放控件

· WebView - 浏览器控件

· RatingBar - 评分控件

· Tab - 选项卡控件

· Spinner - 下拉框控件

· Chronometer - 计时器控件

· ScrollView - 滚动条控件

1、ZoomControls 的 Demo zoomcontrols.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">  <ZoomControls android:id="@+id/zoomControls" android:layout_width="wrap_content" android:layout_height="wrap_content"></ZoomControls> </LinearLayout>

_ZoomControls.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Toast; import android.widget.ZoomControls; public class _ZoomControls extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.zoomcontrols); setTitle("ZoomControls"); ZoomControls zoomControls = (ZoomControls) this.findViewById(R.id.zoomControls); // setOnZoomInClickListener() - 响应单击放大按钮的事件 zoomControls.setOnZoomInClickListener(new OnClickListener() { public void onClick(View v) { Toast.makeText(_ZoomControls.this, "单击了放大按钮", Toast.LENGTH_SHORT).show(); } }); // setOnZoomOutClickListener() - 响应单击缩小按钮的事件 zoomControls.setOnZoomOutClickListener(new OnClickListener() { public void onClick(View v) { Toast.makeText(_ZoomControls.this, "单击了缩小按钮", Toast.LENGTH_SHORT).show(); } }); } }

2、Include 的 Demo include.xml

代码

include_1.xml

代码

<?xml version="1.0" encoding="utf-8"?> <TextView xmlns:android="http://schemas.android.com/apk/res/android" android:text="TextView01" android:layout_width="wrap_content" android:layout_height="wrap_content"> </TextView>

include_2.xml

代码

<?xml version="1.0" encoding="utf-8"?> <TextView xmlns:android="http://schemas.android.com/apk/res/android" android:text="TextView02" android:layout_width="wrap_content" android:layout_height="wrap_content"> </TextView>

_Include.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; public class _Include extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.include); setTitle("Include"); } }

3、VideoView 的 Demo videoview.xml

代码

_VideoView.java

代码

package com.webabcd.view; import android.app.Activity; import android.net.Uri; import android.os.Bundle; import android.widget.MediaController; import android.widget.VideoView; public class _VideoView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.videoview); setTitle("VideoView"); VideoView videoView = (VideoView) findViewById(R.id.videoView); // 指定需要播放的视频的地址 videoView.setVideoURI(Uri.parse("android.resource://com.webabcd.view/" + R.raw.demo)); // videoView.setVideoPath(); // 设置播放器的控制条 videoView.setMediaController(new MediaController(this)); // 开始播放视频 videoView.start(); } }

4、WebView 的 Demo webview.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent">  <WebView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/webView" /> </LinearLayout>

_WebView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.webkit.WebSettings; import android.webkit.WebView; public class _WebView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.webview); setTitle("WebView"); WebView webView = (WebView) findViewById(R.id.webView); // 配置浏览器，使其可支持 JavaScript WebSettings webSettings = webView.getSettings(); webSettings.setJavaScriptEnabled(true); // 清除浏览器缓存 webView.clearCache(true); // 指定浏览器需要解析的 url 地址 webView.loadUrl("http://webabcd.cnblogs.com/"); // 指定浏览器需要解析的 html 数据 // webView.loadData("<a href='http://webabcd.cnblogs.com/'>webabcd</a>", "text/html", "utf-8"); } }

5、RatingBar 的 Demo ratingbar.xml

代码

_RatingBar.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.RatingBar; import android.widget.TextView; public class _RatingBar extends Activity implements RatingBar.OnRatingBarChangeListener { private RatingBar mRatingBar; private TextView mTextView; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.ratingbar); setTitle("RatingBar"); mTextView = (TextView) findViewById(R.id.textView); mRatingBar = (RatingBar) findViewById(R.id.ratingBar); // setOnRatingBarChangeListener() - 响应评分值发生改变的事件 mRatingBar.setOnRatingBarChangeListener(this); } @Override public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) { mTextView.setText(String.valueOf(rating)); } }

6、Tab 的 Demo tab.xml

代码

<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent">  <TextView android:id="@+id/view1" android:layout_width="fill_parent" android:layout_height="fill_parent" android:text="tab1 content" />  <TextView android:id="@+id/view2" android:layout_width="fill_parent" android:layout_height="fill_parent" android:text="tab2 content" /> </FrameLayout>

_Tab.java

代码

package com.webabcd.view; import android.app.TabActivity; import android.content.Intent; import android.os.Bundle; import android.view.LayoutInflater; import android.widget.TabHost; // 实现 Tab 功能的话要继承 TabActivity public class _Tab extends TabActivity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); TabHost tabHost = getTabHost(); LayoutInflater.from(this).inflate(R.layout.tab, tabHost.getTabContentView(), true); // Tab 1 的内容 tabHost.addTab(tabHost.newTabSpec("tab1") .setIndicator("tab1") .setContent(R.id.view1)); // Tab 2 的内容（设置了 Tab 图片） tabHost.addTab(tabHost.newTabSpec("tab2") .setIndicator("tab2", getResources().getDrawable(R.drawable.icon01)) .setContent(R.id.view2)); // Tab 3 的内容（设置 Tab 的内容为指定的 Activity） tabHost.addTab(tabHost.newTabSpec("tab3") .setIndicator("tab3") .setContent(new Intent(this, _TextView.class))); } }

7、Spinner 的 Demo spinner.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/textView" />  <Spinner android:id="@+id/spinner" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>

_Spinner.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.ArrayAdapter; import android.widget.Spinner; import android.widget.TextView; public class _Spinner extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.spinner); setTitle("Spinner"); Spinner spinner = (Spinner) findViewById(R.id.spinner); // 设置下拉框控件的标题文本 spinner.setPrompt("请选择"); // 实例化适配器，指定显示格式及数据源 ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource( this, R.array.colors, android.R.layout.simple_spinner_item); adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item); spinner.setAdapter(adapter); // setOnItemSelectedListener() - 响应下拉框的选中值发生变化的事件 spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) { TextView textView = (TextView)_Spinner.this.findViewById(R.id.textView); textView.setText(((TextView)arg1).getText()); } @Override public void onNothingSelected(AdapterView<?> arg0) { } }); } }

8、Chronometer 的 Demo chronometer.xml

代码

_Chronometer.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.os.SystemClock; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.Chronometer; public class _Chronometer extends Activity { private Chronometer mChronometer; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.chronometer); setTitle("Chronometer"); Button button; mChronometer = (Chronometer) findViewById(R.id.chronometer); // 设置计时器所显示的时间格式 mChronometer.setFormat("计时：(%s)"); button = (Button) findViewById(R.id.btnStart); button.setOnClickListener(mStartListener); button = (Button) findViewById(R.id.btnStop); button.setOnClickListener(mStopListener); button = (Button) findViewById(R.id.btnReset); button.setOnClickListener(mResetListener); } View.OnClickListener mStartListener = new OnClickListener() { public void onClick(View v) { // 启动计时器 mChronometer.start(); } }; View.OnClickListener mStopListener = new OnClickListener() { public void onClick(View v) { // 暂停计时器 mChronometer.stop(); } }; View.OnClickListener mResetListener = new OnClickListener() { public void onClick(View v) { // 复位计时器，即停止计时器 mChronometer.setBase(SystemClock.elapsedRealtime()); } }; }

9、ScrollView 的 Demo scrollview.xml

代码

_ScrollView.java

代码

package com.webabcd.view; import android.app.Activity; import android.os.Bundle; import android.widget.TextView; public class _ScrollView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.scrollview); setTitle("ScrollView"); TextView textView = (TextView)this.findViewById(R.id.textView); textView.setText("a\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na\na"); } }

Android(8) - 控件(View)之TextSwitcher, Gallery, ImageSwitcher, GridView, ListView, ExpandableList

介绍在 Android 中使用各种控件(View)

· TextSwitcher - 文字转换器控件（改变文字时增加一些动画效果）

· Gallery - 缩略图浏览器控件

· ImageSwitcher - 图片转换器控件（改变图片时增加一些动画效果）

· GridView - 网格控件

· ListView - 列表控件

· ExpandableList - 支持展开/收缩功能的列表控件

1、TextSwitcher 的 Demo textswitcher.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <Button android:id="@+id/btnChange" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="改变文字" />  <TextSwitcher android:id="@+id/textSwitcher" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>

_TextSwitcher.java

代码

package com.webabcd.view; import java.util.Random; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.animation.Animation; import android.view.animation.AnimationUtils; import android.widget.Button; import android.widget.TextSwitcher; import android.widget.TextView; import android.widget.ViewSwitcher; public class _TextSwitcher extends Activity implements ViewSwitcher.ViewFactory { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.textswithcer); setTitle("TextSwithcer"); final TextSwitcher switcher = (TextSwitcher) findViewById(R.id.textSwitcher); // 指定转换器的 ViewSwitcher.ViewFactory switcher.setFactory(this); // 设置淡入和淡出的动画效果 Animation in = AnimationUtils.loadAnimation(this, android.R.anim.fade_in); Animation out = AnimationUtils.loadAnimation(this, android.R.anim.fade_out); switcher.setInAnimation(in); switcher.setOutAnimation(out); // 单击一次按钮改变一次文字 Button btnChange = (Button) this.findViewById(R.id.btnChange); btnChange.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { switcher.setText(String.valueOf(new Random().nextInt())); } }); } // 重写 ViewSwitcher.ViewFactory 的 makeView()，返回一个 View @Override public View makeView() { TextView textView = new TextView(this); textView.setTextSize(36); return textView; } }

2、Gallery 的 Demo gallery.xml

代码

_Gallery.java

代码

package com.webabcd.view; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.BaseAdapter; import android.widget.Gallery; import android.widget.ImageView; import android.widget.Toast; import android.widget.Gallery.LayoutParams; public class _Gallery extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.gallery); setTitle("Gallery"); Gallery gallery = (Gallery) findViewById(R.id.gallery); // 为缩略图浏览器指定一个适配器 gallery.setAdapter(new ImageAdapter(this)); // 响应在缩略图列表上选中某个缩略图后的事件 gallery.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> parent, View v, int position, long id) { Toast.makeText(_Gallery.this, String.valueOf(position), Toast.LENGTH_SHORT).show(); } @Override public void onNothingSelected(AdapterView<?> arg0) { } }); } // 继承 BaseAdapter 用以实现自定义的图片适配器 public class ImageAdapter extends BaseAdapter { private Context mContext; public ImageAdapter(Context context) { mContext = context; } public int getCount() { return mThumbIds.length; } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { ImageView image = new ImageView(mContext); image.setImageResource(mThumbIds[position]); image.setAdjustViewBounds(true); image.setLayoutParams(new Gallery.LayoutParams( LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); return image; } } // 需要显示的图片集合 private Integer[] mThumbIds = { R.drawable.icon01, R.drawable.icon02, R.drawable.icon03, R.drawable.icon04, R.drawable.icon05 }; }

3、ImageSwitcher 的 Demo imageswitcher.xml

代码

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <Gallery android:id="@+id/gallery" android:layout_width="fill_parent" android:layout_height="wrap_content" android:spacing="20px" />  <ImageSwitcher android:id="@+id/imageSwitcher" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>

_ImageSwitcher.java

代码

package com.webabcd.view; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.ViewGroup; import android.view.animation.AnimationUtils; import android.widget.AdapterView; import android.widget.BaseAdapter; import android.widget.Gallery; import android.widget.ImageSwitcher; import android.widget.ImageView; import android.widget.ViewSwitcher; import android.widget.Gallery.LayoutParams; // 图片转换器的使用基本同文字转换器 // 以下是一个用 ImageSwitcher + Gallery 实现的经典的图片浏览器的 Demo public class _ImageSwitcher extends Activity implements ViewSwitcher.ViewFactory { private ImageSwitcher mSwitcher; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.imageswithcer); setTitle("ImageSwithcer"); mSwitcher = (ImageSwitcher) findViewById(R.id.imageSwitcher); mSwitcher.setFactory(this); mSwitcher.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_in)); mSwitcher.setOutAnimation(AnimationUtils.loadAnimation(this, android.R.anim.fade_out)); Gallery gallery = (Gallery) findViewById(R.id.gallery); gallery.setAdapter(new ImageAdapter(this)); gallery.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView<?> parent, View v, int position, long id) { mSwitcher.setImageResource(mImageIds[position]); } @Override public void onNothingSelected(AdapterView<?> arg0) { } }); } public class ImageAdapter extends BaseAdapter { private Context mContext; public ImageAdapter(Context context) { mContext = context; } public int getCount() { return mThumbIds.length; } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { ImageView image = new ImageView(mContext); image.setImageResource(mThumbIds[position]); image.setAdjustViewBounds(true); image.setLayoutParams(new Gallery.LayoutParams( LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT)); return image; } } private Integer[] mThumbIds = { R.drawable.icon01, R.drawable.icon02, R.drawable.icon03, R.drawable.icon04, R.drawable.icon05 }; private Integer[] mImageIds = { R.drawable.icon01, R.drawable.icon02, R.drawable.icon03, R.drawable.icon04, R.drawable.icon05 }; @Override public View makeView() { ImageView image = new ImageView(this); image.setMinimumHeight(200); image.setMinimumWidth(200); image.setScaleType(ImageView.ScaleType.FIT_CENTER); image.setLayoutParams(new ImageSwitcher.LayoutParams( LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT)); return image; } }

4、GridView 的 Demo gridview.xml

代码

<?xml version="1.0" encoding="utf-8"?>  <GridView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/gridView" android:layout_width="fill_parent" android:layout_height="fill_parent" android:padding="10px" android:verticalSpacing="10px" android:horizontalSpacing="10px" android:numColumns="auto_fit" android:columnWidth="60px" android:stretchMode="columnWidth" android:gravity="center"> </GridView>

_GridView.java

代码

package com.webabcd.view; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.GridView; import android.widget.ImageView; public class _GridView extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); this.setContentView(R.layout.gridview); setTitle("GridView"); GridView gridView = (GridView) findViewById(R.id.gridView); // 指定网格控件的适配器为自定义的图片适配器 gridView.setAdapter(new ImageAdapter(this)); } // 自定义的图片适配器 public class ImageAdapter extends BaseAdapter { private Context mContext; public ImageAdapter(Context context) { mContext = context; } public int getCount() { return mThumbIds.length; } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { ImageView imageView; if (convertView == null) { imageView = new ImageView(mContext); imageView.setLayoutParams(new GridView.LayoutParams(48, 48)); imageView.setAdjustViewBounds(false); imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); imageView.setPadding(5, 5, 5, 5); } else { imageView = (ImageView) convertView; } imageView.setImageResource(mThumbIds[position]); return imageView; } // 网格控件所需图片数据的数据源 private Integer[] mThumbIds = { R.drawable.icon01, R.drawable.icon02, R.drawable.icon03, R.drawable.icon04, R.drawable.icon05 }; } }

5、ListView 的 Demo main_list_adapter.xml

代码

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent"> <TextView android:id="@+id/text" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="16sp"> </TextView> </LinearLayout>

MainListAdapter.java

代码

package com.webabcd.view; import java.util.List; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.TextView; // 继承 BaseAdapter 以实现自定义的列表适配器 public class MainListAdapter extends BaseAdapter { private LayoutInflater mInflater; private List<String> mData; public MainListAdapter(Context context, List<String> data) { mInflater = LayoutInflater.from(context); mData = data; } @Override public int getCount() { return mData.size(); } @Override public Object getItem(int position) { return mData.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { TextView text; if (convertView == null) { // 指定一个 layout 作为自定义列表适配器的 layout convertView = mInflater.inflate(R.layout.main_list_adapter, null); text = (TextView) convertView.findViewById(R.id.text); convertView.setTag(text); } else { text = (TextView) convertView.getTag(); } String mItem = mData.get(position); text.setText(mItem); return convertView; } }

Main.java

代码

package com.webabcd.view; import java.util.ArrayList; import java.util.List; import android.app.ListActivity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.ListView; // 此处要继承 ListActivity ，用以实现 ListView 的功能 public class Main extends ListActivity { private List<String> mData; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setTheme(android.R.style.Theme_Light); setContentView(R.layout.main); mData = getData(); // 使用自定义的列表适配器来展现数据 MainListAdapter adapter = new MainListAdapter(this, mData); // 如需使用系统内置的列表适配器，则可以使用类似如下的方法 // ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, mData); this.setListAdapter(adapter); } // ListView 的数据源 private List<String> getData() { List<String> items = new ArrayList<String>(); items.add("TextView"); items.add("Button"); items.add("ImageButton"); items.add("ImageView"); items.add("CheckBox"); items.add("RadioButton"); items.add("AnalogClock"); items.add("DigitalClock"); items.add("DatePicker"); items.add("TimePicker"); items.add("ToggleButton"); items.add("EditText"); items.add("ProgressBar"); items.add("SeekBar"); items.add("AutoCompleteTextView"); items.add("MultiAutoCompleteTextView"); items.add("ZoomControls"); items.add("Include"); items.add("VideoView"); items.add("WebView"); items.add("RatingBar"); items.add("Tab"); items.add("Spinner"); items.add("Chronometer"); items.add("ScrollView"); items.add("TextSwitcher"); items.add("ListView"); items.add("Gallery"); items.add("ImageSwitcher"); items.add("GridView"); items.add("ExpandableList"); return items; } // ListView 中某项被选中后的逻辑 @Override protected void onListItemClick(ListView l, View v, int position, long id) { Intent intent = new Intent(); intent.setClassName(this, "com.webabcd.view._" + mData.get(position)); startActivityForResult(intent, 0); } }

6、ExpandableList 的 Demo _ExpandableList.java

代码

package com.webabcd.view; import android.app.ExpandableListActivity; import android.os.Bundle; import android.view.ContextMenu; import android.view.Gravity; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.view.ContextMenu.ContextMenuInfo; import android.widget.AbsListView; import android.widget.BaseExpandableListAdapter; import android.widget.ExpandableListAdapter; import android.widget.ExpandableListView; import android.widget.TextView; import android.widget.Toast; import android.widget.ExpandableListView.ExpandableListContextMenuInfo; // ExpandableList - 可展开/收缩列表 // 继承 ExpandableListActivity 以实现列表的可展开/收缩的功能 public class _ExpandableList extends ExpandableListActivity { private ExpandableListAdapter mAdapter; @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setTitle("ExpandableList"); mAdapter = new MyExpandableListAdapter(); setListAdapter(mAdapter); registerForContextMenu(this.getExpandableListView()); } // 为列表的每一项创建上下文菜单（即长按后呼出的菜单） @Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) { menu.setHeaderTitle("ContextMenu"); menu.add(0, 0, 0, "ContextMenu"); } // 单击上下文菜单后的逻辑 @Override public boolean onContextItemSelected(MenuItem item) { ExpandableListContextMenuInfo info = (ExpandableListContextMenuInfo) item.getMenuInfo(); String title = ((TextView) info.targetView).getText().toString(); int type = ExpandableListView.getPackedPositionType(info.packedPosition); if (type == ExpandableListView.PACKED_POSITION_TYPE_CHILD) { int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); int childPos = ExpandableListView.getPackedPositionChild(info.packedPosition); Toast.makeText(this, title + " - Group Index: " + groupPos + " Child Index: " + childPos, Toast.LENGTH_SHORT).show(); return true; } else if (type == ExpandableListView.PACKED_POSITION_TYPE_GROUP) { int groupPos = ExpandableListView.getPackedPositionGroup(info.packedPosition); Toast.makeText(this, title + " - Group Index: " + groupPos, Toast.LENGTH_SHORT).show(); return true; } return false; } public class MyExpandableListAdapter extends BaseExpandableListAdapter { // 父列表数据 private String[] groups = { "group1", "group2", "group3", "group4" }; // 子列表数据 private String[][] children = { { "child1" }, { "child1", "child2" }, { "child1", "child2", "child3" }, { "child1", "child2", "child3", "child4" } }; @Override public Object getChild(int groupPosition, int childPosition) { return children[groupPosition][childPosition]; } @Override public long getChildId(int groupPosition, int childPosition) { return childPosition; } @Override public int getChildrenCount(int groupPosition) { return children[groupPosition].length; } // 取子列表中的某一项的 View @Override public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) { TextView textView = getGenericView(); textView.setText(getChild(groupPosition, childPosition).toString()); return textView; } @Override public Object getGroup(int groupPosition) { return groups[groupPosition]; } @Override public int getGroupCount() { return groups.length; } @Override public long getGroupId(int groupPosition) { return groupPosition; } // 取父列表中的某一项的 View @Override public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) { TextView textView = getGenericView(); textView.setText(getGroup(groupPosition).toString()); return textView; } @Override public boolean hasStableIds() { return true; } @Override public boolean isChildSelectable(int groupPosition, int childPosition) { return true; } // 获取某一项的 View 的逻辑 private TextView getGenericView() { AbsListView.LayoutParams lp = new AbsListView.LayoutParams( ViewGroup.LayoutParams.FILL_PARENT, 48); TextView textView = new TextView(_ExpandableList.this); textView.setLayoutParams(lp); textView.setGravity(Gravity.CENTER_VERTICAL | Gravity.LEFT); textView.setPadding(32, 0, 0, 0); return textView; } } }

Android(9) - 数据库支持(SQLite), 内容提供器(ContentProvider)

介绍在 Android 中使用 SQLite, ContentProvider

· 数据库支持(SQLite) - Android 开发平台提供了操作 SQLite 数据库的相关 API

· 内容提供器(ContentProvider) - 当数据需要在应用程序之间共享时，可以在某程序中使用 ContentProvider 定义 URI，以使其它应用程序可以通过此 URI 访问指定的数据

1、SQLite 的 Demo DatabaseHelper.java

代码

package com.webabcd.SQLite; import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import android.database.sqlite.SQLiteDatabase.CursorFactory; // 数据库操作的 Helper 类 public class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context, String name, CursorFactory cursorFactory, int version) { super(context, name, cursorFactory, version); } @Override public void onCreate(SQLiteDatabase db) { // TODO 创建数据库后，对数据库的操作 } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // TODO 更改数据库版本的操作 } @Override public void onOpen(SQLiteDatabase db) { super.onOpen(db); // TODO 每次成功打开数据库后首先被执行 } }

Main.java

代码

package com.webabcd.SQLite; import java.util.Random; import android.app.Activity; import android.content.ContentValues; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; public class Main extends Activity { private DatabaseHelper dbHelper; private static final String DATABASE_NAME = "db.db"; private static final int DATABASE_VERSION = 1; private static final String TABLE_NAME = "employee"; TextView txtMsg; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); dbHelper = new DatabaseHelper(this, DATABASE_NAME, null, DATABASE_VERSION); txtMsg = (TextView) this.findViewById(R.id.txtMsg); Button btn1 = (Button) this.findViewById(R.id.btn1); btn1.setText("创建表"); btn1.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { CreateTable(); } }); Button btn2 = (Button) this.findViewById(R.id.btn2); btn2.setText("插入 3 条记录"); btn2.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { insertItem(); } }); Button btn3 = (Button) this.findViewById(R.id.btn3); btn3.setText("删除全部记录"); btn3.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { deleteItem(); } }); Button btn4 = (Button) this.findViewById(R.id.btn4); btn4.setText("更新指定数据"); btn4.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { updateItem(); } }); Button btn5 = (Button) this.findViewById(R.id.btn5); btn5.setText("显示全部数据"); btn5.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { showItems(); } }); Button btn6 = (Button) this.findViewById(R.id.btn6); btn6.setText("删除表"); btn6.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { dropTable(); } }); } // 创建数据表 private void CreateTable() { SQLiteDatabase db = dbHelper.getWritableDatabase(); String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_NAME + " (ID INTEGER PRIMARY KEY, Name VARCHAR, Age INTEGER);"; try { db.execSQL(sql); txtMsg.append("数据表成功创建\n"); } catch (SQLException ex) { txtMsg.append("数据表创建错误\n" + ex.toString() + "\n"); } } // 插入数据 private void insertItem() { SQLiteDatabase db = dbHelper.getWritableDatabase(); try { Random random = new Random(); for (int i = 0; i < 3; i++) { String sql = "insert into " + TABLE_NAME + " (name, age) values ('name" + String.valueOf(i) + "', " + random.nextInt() + ")"; // execSQL() - 执行指定的 sql db.execSQL(sql); } txtMsg.append("成功插入 3 条数据\n"); } catch (SQLException ex) { txtMsg.append("插入数据失败\n" + ex.toString() + "\n"); } } // 删除数据 private void deleteItem() { try { SQLiteDatabase db = dbHelper.getWritableDatabase(); db.delete(TABLE_NAME, " id < 999999", null); txtMsg.append("成功删除数据\n"); } catch (SQLException e) { txtMsg.append("删除数据失败\n"); } } // 更新数据 private void updateItem() { SQLiteDatabase db = dbHelper.getWritableDatabase(); try { ContentValues values = new ContentValues(); values.put("name", "批量更新后的名字"); db.update(TABLE_NAME, values, "id<?", new String[] { "3" }); txtMsg.append("成功更新数据\n"); } catch (SQLException e) { txtMsg.append("更新数据失败\n"); } } // 查询数据 private void showItems() { SQLiteDatabase db = dbHelper.getReadableDatabase(); try { String[] column = { "id", "name", "age" }; Cursor cursor = db.query(TABLE_NAME, column, null, null, null, null, null); Integer num = cursor.getCount(); txtMsg.append("共 " + Integer.toString(num) + " 条记录\n"); cursor.moveToFirst(); while (cursor.getPosition() != cursor.getCount()) { txtMsg.append(Integer.toString(cursor.getPosition()) + "," + String.valueOf(cursor.getString(0)) + "," + cursor.getString(1) + "," + String.valueOf(cursor.getString(2)) + "\n"); cursor.moveToNext(); } } catch (SQLException ex) { txtMsg.append("读取数据失败\n" + ex.toString() + "\n"); } } // 删除数据表 private void dropTable() { SQLiteDatabase db = dbHelper.getWritableDatabase(); String sql = "DROP TABLE IF EXISTS " + TABLE_NAME; try { db.execSQL(sql); txtMsg.append("数据表删除成功\n"); } catch (SQLException ex) { txtMsg.append("数据表删除错误\n" + ex.toString() + "\n"); } } }

2、ContentProvider 的 Demo MyUser.java

代码

package com.webabcd.contentprovider; import android.net.Uri; import android.provider.BaseColumns; // 自定义 ContentProvider 所需的实体类 public class MyUser { // 必须要有 _id 字段。本例中 BaseColumn 类中已经包含了 _id 字段 public static final class User implements BaseColumns { // 定义 CONTENT_URI public static final Uri CONTENT_URI = Uri.parse("content://com.webabcd.MyContentProvider"); // 表数据列 public static final String USER_NAME = "USER_NAME"; } }

MyContentProvider.java

代码

package com.webabcd.contentprovider; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import org.apache.http.util.EncodingUtils; import android.content.ContentProvider; import android.content.ContentUris; import android.content.ContentValues; import android.database.Cursor; import android.database.MatrixCursor; import android.net.Uri; // 继承 ContentProvider 以实现自定义的 ContentProvider（基于文件的信息存储） public class MyContentProvider extends ContentProvider { private File file; private FileOutputStream out; private FileInputStream in; // ContentProvider 的删除数据接口 @Override public int delete(Uri uri, String selection, String[] selectionArgs) { // TODO Auto-generated method stub return 0; } @Override public String getType(Uri uri) { // TODO Auto-generated method stub return null; } // ContentProvider 的插入数据接口 @Override public Uri insert(Uri uri, ContentValues values) { try { out = new FileOutputStream(file); out.write(values.getAsString(MyUser.User.USER_NAME).getBytes()); out.close(); int rowId = 0; Uri rowUri = ContentUris.appendId( MyUser.User.CONTENT_URI.buildUpon(), rowId).build(); getContext().getContentResolver().notifyChange(rowUri, null); return rowUri; } catch (Exception e) { return null; } } // 创建用于保存信息的文件 @Override public boolean onCreate() { try { // 每个包中应用程序的私有目录为：/data/data/包名/ // SD 卡目录为：/sdcard file = new File("/data/data/com.webabcd.contentprovider/", "demo.txt"); if (!file.exists()) file.createNewFile(); return true; } catch (Exception ex) { return false; } } // ContentProvider 的查询数据接口 @Override public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) { String content; try { in = new FileInputStream(file); int length = (int) file.length(); byte[] buffer = new byte[length]; in.read(buffer, 0, length); content = EncodingUtils.getString(buffer, "UTF-8"); in.close(); String[] columns = new String[] { MyUser.User._ID, MyUser.User.USER_NAME }; MatrixCursor cur = new MatrixCursor(columns); String[] values = new String[] { "0", content }; cur.moveToFirst(); cur.addRow(values); return cur; } catch (Exception e) { return null; } } // ContentProvider 的更新数据接口 @Override public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) { // TODO Auto-generated method stub return 0; } }

Main.java

代码

的联系人记录） */ public class Main extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button btn1 = (Button) this.findViewById(R.id.btn1); btn1.setText("新增联系人记录"); btn1.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { Random random = new Random(); insertRecords("name" + String.valueOf(random.nextInt()), String .valueOf(random.nextInt())); } }); Button btn2 = (Button) this.findViewById(R.id.btn2); btn2.setText("查看联系人记录"); btn2.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { displayRecords(); } }); Button btn3 = (Button) this.findViewById(R.id.btn3); btn3.setText("清除联系人记录"); btn3.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { deleteRecords(); } }); Button btn4 = (Button) this.findViewById(R.id.btn4); btn4.setText("更新联系人记录"); btn4.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { // 此处只是演示，id 来自 People._ID ，可参见 displayRecords() 是如何获取 id 的 int id = 0; updateRecord(id, "修改后的name"); } }); Button btn5 = (Button) this.findViewById(R.id.btn5); btn5.setText("新增记录到 MyContentProvider"); btn5.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { insertRecord2MyContentProvider("webabcd"); } }); Button btn6 = (Button) this.findViewById(R.id.btn6); btn6.setText("获取记录从 MyContentProvider"); btn6.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { displayRecord2MyContentProvider(); } }); } // 调用 ContentProvider 的插入接口 private void insertRecords(String name, String phoneNum) { ContentValues values = new ContentValues(); values.put(People.NAME, name); Uri uri = getContentResolver().insert(People.CONTENT_URI, values); Log.d("MyDebug", uri.toString()); Uri numberUri = Uri.withAppendedPath(uri, People.Phones.CONTENT_DIRECTORY); Log.d("MyDebug", numberUri.toString()); values.clear(); values.put(Contacts.Phones.TYPE, People.Phones.TYPE_MOBILE); values.put(People.NUMBER, phoneNum); getContentResolver().insert(numberUri, values); } // 调用 ContentProvider 的查询接口 private void displayRecords() { String[] columns = new String[] { People._ID, People.NAME, People.NUMBER }; Uri contacts = People.CONTENT_URI; Log.d("MyDebug", contacts.toString()); Cursor cur = managedQuery(contacts, columns, // 要返回的数据字段 null, // WHERE子句 null, // WHERE 子句的参数 null // Order-by子句 ); if (cur.moveToFirst()) { String id = null; String name = null; String phoneNo = null; while (cur.getPosition() != cur.getCount()) { id = cur.getString(cur.getColumnIndex(People._ID)); name = cur.getString(cur.getColumnIndex(People.NAME)); phoneNo = cur.getString(cur.getColumnIndex(People.NUMBER)); Toast.makeText(this, id + " / " + name + " / " + phoneNo, Toast.LENGTH_SHORT).show(); cur.moveToNext(); } } } // 调用 ContentProvider 的删除接口 private void deleteRecords() { Uri uri = People.CONTENT_URI; Log.d("MyDebug", uri.toString()); getContentResolver().delete(uri, null, null); // getContentResolver().delete(uri, "NAME=" + "'name'", null); } // 调用 ContentProvider 的更新接口 private void updateRecord(int recordNo, String name) { Uri uri = ContentUris.withAppendedId(People.CONTENT_URI, recordNo); Log.d("MyDebug", uri.toString()); ContentValues values = new ContentValues(); values.put(People.NAME, name); getContentResolver().update(uri, values, null, null); } // 调用自定义 ContentProvider 的插入接口 private void insertRecord2MyContentProvider(String name) { ContentValues values = new ContentValues(); values.put(MyUser.User.USER_NAME, name); getContentResolver().insert(MyUser.User.CONTENT_URI, values); } // 调用自定义 ContentProvider 的查询接口 private void displayRecord2MyContentProvider() { String[] columns = new String[] { MyUser.User.USER_NAME }; Uri uri = MyUser.User.CONTENT_URI; Cursor cur = managedQuery(uri, columns, null, null, null); while (cur.getPosition() != cur.getCount()) { String id = cur.getString(cur.getColumnIndex(People._ID)); String name = cur.getString(cur.getColumnIndex(MyUser.User.USER_NAME)); Toast.makeText(this, id + " / " + name, Toast.LENGTH_SHORT).show(); cur.moveToNext(); } } }

AndroidManifest.xml

代码

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.webabcd.contentprovider" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".Main" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity>  <provider android:name="MyContentProvider" android:authorities="com.webabcd.MyContentProvider" /> </application> <uses-permission android:name="android.permission.WRITE_CONTACTS"></uses-permission> <uses-permission android:name="android.permission.READ_CONTACTS"></uses-permission> <uses-sdk android:minSdkVersion="3" /> </manifest>

Android(10) - HTTP 通信, XML 解析, 通过 Hander 实现异步消息处理

介绍在 Android 中与服务端做 HTTP 通信，解析 XML，通过 Handler 实现异步消息处理

· HTTP 通信 - 与服务端做 HTTP 通信，分别以 GET 方式和 POST 方式做演示

· XML 解析 - 可以用两种方式解析 XML，分别是 DOM 方式和 SAX 方式

· 异步消息处理 - 通过 Handler 实现异步消息处理，以一个自定义的异步下载类来说明 Handler 的用法

1、HTTP 通信和 XML 解析的 Demo MySAXHandler.java

代码

package com.webabcd.communication; import org.xml.sax.Attributes; import org.xml.sax.SAXException; import org.xml.sax.helpers.DefaultHandler; // 继承 DefaultHandler 以实现指定 XML 的 SAX 解析器 // DOM - W3C 标准，需要把 xml 数据全部加载完成后才能对其做解析，可对树做任意遍历 // SAX - 流式解析，通过事件模型解析 xml，只能顺序解析 public class MySAXHandler extends DefaultHandler { private boolean mIsTitleTag = false; private boolean mIsSalaryTag = false; private boolean mIsBirthTag = false; private String mResult = ""; // 打开 xml 文档的回调函数 @Override public void startDocument() throws SAXException { // TODO Auto-generated method stub super.startDocument(); } // 关闭 xml 文档的回调函数 @Override public void endDocument() throws SAXException { // TODO Auto-generated method stub super.endDocument(); } // 一发现元素开始标记就回调此函数 @Override public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException { if (localName == "title") mIsTitleTag = true; else if (localName == "salary") mIsSalaryTag = true; else if (localName == "dateOfBirth") mIsBirthTag = true; else if (localName == "employee") mResult += "\nname:" + attributes.getValue("name"); } // 一发现元素结束标记就回调此函数 @Override public void endElement(String uri, String localName, String qName) throws SAXException { if (localName == "title") mIsTitleTag = false; else if (localName == "salary") mIsSalaryTag = false; else if (localName == "dateOfBirth") mIsBirthTag = false; } // 一发现元素值或属性值就回调此函数 @Override public void characters(char[] ch, int start, int length) throws SAXException { if (mIsTitleTag) mResult += new String(ch, start, length); else if (mIsSalaryTag) mResult += " salary:" + new String(ch, start, length); else if (mIsBirthTag) mResult += " dateOfBirth:" + new String(ch, start, length); } public String getResult(){ return mResult; } }

Main.java

代码

package com.webabcd.communication; import java.io.BufferedInputStream; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.util.ArrayList; import java.util.HashMap; import java.util.Map; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import org.apache.http.protocol.HTTP; import org.apache.http.util.ByteArrayBuffer; import org.apache.http.util.EncodingUtils; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; import org.xml.sax.XMLReader; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.TextView; public class Main extends Activity { private TextView textView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); textView = (TextView) this.findViewById(R.id.textView); Button btn1 = (Button) this.findViewById(R.id.btn1); btn1.setText("http get demo"); btn1.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { httpGetDemo(); } }); Button btn2 = (Button) this.findViewById(R.id.btn2); btn2.setText("http post demo"); btn2.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { httpPostDemo(); } }); Button btn3 = (Button) this.findViewById(R.id.btn3); // DOM - Document Object Model btn3.setText("DOM 解析 XML"); btn3.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { DOMDemo(); } }); Button btn4 = (Button) this.findViewById(R.id.btn4); // SAX - Simple API for XML btn4.setText("SAX 解析 XML"); btn4.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { SAXDemo(); } }); } // Android 调用 http 协议的 get 方法 // 本例：以 http 协议的 get 方法获取远程页面响应的内容 private void httpGetDemo(){ try { // 模拟器测试时，请使用外网地址 URL url = new URL("http://xxx.xxx.xxx"); URLConnection con = url.openConnection(); String result = "http status code: " + ((HttpURLConnection)con).getResponseCode() + "\n"; // HttpURLConnection.HTTP_OK InputStream is = con.getInputStream(); BufferedInputStream bis = new BufferedInputStream(is); ByteArrayBuffer bab = new ByteArrayBuffer(32); int current = 0; while ( (current = bis.read()) != -1 ){ bab.append((byte)current); } result += EncodingUtils.getString(bab.toByteArray(), HTTP.UTF_8); bis.close(); is.close(); textView.setText(result); } catch (Exception e) { textView.setText(e.toString()); } } // Android 调用 http 协议的 post 方法 // 本例：以 http 协议的 post 方法向远程页面传递参数，并获取其响应的内容 private void httpPostDemo(){ try { // 模拟器测试时，请使用外网地址 String url = "http://5billion.com.cn/post.php"; Map<String, String> data = new HashMap<String, String>(); data.put("name", "webabcd"); data.put("salary", "100"); DefaultHttpClient httpClient = new DefaultHttpClient(); HttpPost httpPost = new HttpPost(url); ArrayList<BasicNameValuePair> postData = new ArrayList<BasicNameValuePair>(); for (Map.Entry<String, String> m : data.entrySet()) { postData.add(new BasicNameValuePair(m.getKey(), m.getValue())); } UrlEncodedFormEntity entity = new UrlEncodedFormEntity(postData, HTTP.UTF_8); httpPost.setEntity(entity); HttpResponse response = httpClient.execute(httpPost); String result = "http status code: " + response.getStatusLine().getStatusCode() + "\n"; // HttpURLConnection.HTTP_OK HttpEntity httpEntity = response.getEntity(); InputStream is = httpEntity.getContent(); result += convertStreamToString(is); textView.setText(result); } catch (Exception e) { textView.setText(e.toString()); } } // 以 DOM 方式解析 XML（xml 数据详见 res/raw/employee.xml） private void DOMDemo(){ try { DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance(); DocumentBuilder docBuilder = docFactory.newDocumentBuilder(); Document doc = docBuilder.parse(this.getResources().openRawResource(R.raw.employee)); Element rootElement = doc.getDocumentElement(); NodeList employeeNodeList = rootElement.getElementsByTagName("employee"); textView.setText("DOMDemo" + "\n"); String title = rootElement.getElementsByTagName("title").item(0).getFirstChild().getNodeValue(); textView.append(title); for (int i=0; i<employeeNodeList.getLength(); i++){ Element employeeElement = ((Element)employeeNodeList.item(i)); String name = employeeElement.getAttribute("name"); String salary = employeeElement.getElementsByTagName("salary").item(0).getFirstChild().getNodeValue(); String dateOfBirth = employeeElement.getElementsByTagName("dateOfBirth").item(0).getFirstChild().getNodeValue(); textView.append("\nname: "+name+" salary: "+salary+" dateOfBirth: " + dateOfBirth); } } catch (Exception e) { textView.setText(e.toString()); } } // 以 SAX 方式解析 XML（xml 数据详见 res/raw/employee.xml） // SAX 解析器的实现详见 MySAXHandler.java private void SAXDemo(){ try { SAXParserFactory saxFactory = SAXParserFactory.newInstance(); SAXParser parser = saxFactory.newSAXParser(); XMLReader reader = parser.getXMLReader(); MySAXHandler handler = new MySAXHandler(); reader.setContentHandler(handler); reader.parse(new InputSource(this.getResources().openRawResource(R.raw.employee))); String result = handler.getResult(); textView.setText("SAXDemo" + "\n"); textView.append(result); } catch (Exception e) { textView.setText(e.toString()); } } // 辅助方法，用于把流转换为字符串 private String convertStreamToString(InputStream is) { BufferedReader reader = new BufferedReader(new InputStreamReader(is)); StringBuilder sb = new StringBuilder(); String line = null; try { while ((line = reader.readLine()) != null) { sb.append(line + "\n"); } } catch (IOException e) { e.printStackTrace(); } finally { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } return sb.toString(); }}

2、用 Handler 来实现异步消息处理，以一个可以实时汇报下载进度的异步下载类为例开发一个 Android 类库，本例中此类库名为 webabcd_util New -> Java Project 项目上点右键 -> Build Path -> Add Libraries -> User Library -> User Libraries -> New -> 为类库起个名字 -> 选中这个类库 -> Add JARs 导入 Android 的 jar 包项目上点右键 -> Build Path -> Add Libraries -> User Library -> 选择 Android 库 DownloadManagerAsync.java

代码

package webabcd.util; import java.io.BufferedReader; import java.io.File; import java.io.FileOutputStream; import java.io.InputStream; import java.io.InputStreamReader; import java.net.URL; import java.net.URLConnection; import org.apache.http.protocol.HTTP; import android.os.Handler; import android.os.Message; import android.util.Log; // 以一个实例，即异步下载，来演示 Android 的异步消息处理（用 Handler 的方式） public class DownloadManagerAsync { public DownloadManagerAsync() { } // 实例化自定义的 Handler EventHandler mHandler = new EventHandler(this); // 按指定 url 地址下载文件到指定路径 public void download(final String url, final String savePath) { new Thread(new Runnable() { public void run() { try { sendMessage(FILE_DOWNLOAD_CONNECT); URL sourceUrl = new URL(url); URLConnection conn = sourceUrl.openConnection(); InputStream inputStream = conn.getInputStream(); int fileSize = conn.getContentLength(); File savefile = new File(savePath); if (savefile.exists()) { savefile.delete(); } savefile.createNewFile(); FileOutputStream outputStream = new FileOutputStream( savePath, true); byte[] buffer = new byte[1024]; int readCount = 0; int readNum = 0; int prevPercent = 0; while (readCount < fileSize && readNum != -1) { readNum = inputStream.read(buffer); if (readNum > -1) { outputStream.write(buffer); readCount = readCount + readNum; int percent = (int) (readCount * 100 / fileSize); if (percent > prevPercent) { // 发送下载进度信息 sendMessage(FILE_DOWNLOAD_UPDATE, percent, readCount); prevPercent = percent; } } } outputStream.close(); sendMessage(FILE_DOWNLOAD_COMPLETE, savePath); } catch (Exception e) { sendMessage(FILE_DOWNLOAD_ERROR, e); Log.e("MyError", e.toString()); } } }).start(); } // 读取指定 url 地址的响应内容 public void download(final String url) { new Thread(new Runnable() { public void run() { try { sendMessage(FILE_DOWNLOAD_CONNECT); URL sourceUrl = new URL(url); URLConnection conn = sourceUrl.openConnection(); conn.setConnectTimeout(3000); BufferedReader reader = new BufferedReader( new InputStreamReader(conn.getInputStream(), HTTP.UTF_8)); String line = null; StringBuffer content = new StringBuffer(); while ((line = reader.readLine()) != null) { content.append(line); } reader.close(); sendMessage(FILE_DOWNLOAD_COMPLETE, content.toString()); } catch (Exception e) { sendMessage(FILE_DOWNLOAD_ERROR, e); Log.e("MyError", e.toString()); } } }).start(); } // 向 Handler 发送消息 private void sendMessage(int what, Object obj) { // 构造需要向 Handler 发送的消息 Message msg = mHandler.obtainMessage(what, obj); // 发送消息 mHandler.sendMessage(msg); } private void sendMessage(int what) { Message msg = mHandler.obtainMessage(what); mHandler.sendMessage(msg); } private void sendMessage(int what, int arg1, int arg2) { Message msg = mHandler.obtainMessage(what, arg1, arg2); mHandler.sendMessage(msg); } private static final int FILE_DOWNLOAD_CONNECT = 0; private static final int FILE_DOWNLOAD_UPDATE = 1; private static final int FILE_DOWNLOAD_COMPLETE = 2; private static final int FILE_DOWNLOAD_ERROR = -1; // 自定义的 Handler private class EventHandler extends Handler { private DownloadManagerAsync mManager; public EventHandler(DownloadManagerAsync manager) { mManager = manager; } // 处理接收到的消息 @Override public void handleMessage(Message msg) { switch (msg.what) { case FILE_DOWNLOAD_CONNECT: if (mOnDownloadConnectListener != null) mOnDownloadConnectListener.onDownloadConnect(mManager); break; case FILE_DOWNLOAD_UPDATE: if (mOnDownloadUpdateListener != null) mOnDownloadUpdateListener.onDownloadUpdate(mManager, msg.arg1); break; case FILE_DOWNLOAD_COMPLETE: if (mOnDownloadCompleteListener != null) mOnDownloadCompleteListener.onDownloadComplete(mManager, msg.obj); break; case FILE_DOWNLOAD_ERROR: if (mOnDownloadErrorListener != null) mOnDownloadErrorListener.onDownloadError(mManager, (Exception) msg.obj); break; default: break; } } } // 定义连接事件 private OnDownloadConnectListener mOnDownloadConnectListener; public interface OnDownloadConnectListener { void onDownloadConnect(DownloadManagerAsync manager); } public void setOnDownloadConnectListener(OnDownloadConnectListener listener) { mOnDownloadConnectListener = listener; } // 定义下载进度更新事件 private OnDownloadUpdateListener mOnDownloadUpdateListener; public interface OnDownloadUpdateListener { void onDownloadUpdate(DownloadManagerAsync manager, int percent); } public void setOnDownloadUpdateListener(OnDownloadUpdateListener listener) { mOnDownloadUpdateListener = listener; } // 定义下载完成事件 private OnDownloadCompleteListener mOnDownloadCompleteListener; public interface OnDownloadCompleteListener { void onDownloadComplete(DownloadManagerAsync manager, Object result); } public void setOnDownloadCompleteListener( OnDownloadCompleteListener listener) { mOnDownloadCompleteListener = listener; } // 定义下载异常事件 private OnDownloadErrorListener mOnDownloadErrorListener; public interface OnDownloadErrorListener { void onDownloadError(DownloadManagerAsync manager, Exception e); } public void setOnDownloadErrorListener(OnDownloadErrorListener listener) { mOnDownloadErrorListener = listener; }}

调用上面的自定义的 Android 类库项目上点右键 -> Properties -> Java Build Path -> Projects -> Add 引用上面的类库 Main.java

代码

package com.webabcd.handler; import android.app.Activity; import android.os.Bundle; import android.widget.TextView; import webabcd.util.DownloadManagerAsync; public class Main extends Activity implements DownloadManagerAsync.OnDownloadCompleteListener, DownloadManagerAsync.OnDownloadUpdateListener, DownloadManagerAsync.OnDownloadErrorListener { TextView txt; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); DownloadManagerAsync manager = new DownloadManagerAsync(); manager.setOnDownloadCompleteListener(this); manager.setOnDownloadUpdateListener(this); manager.download("http://files.cnblogs.com/webabcd/Android.rar", "/sdcard/Android.rar"); txt = (TextView) this.findViewById(R.id.txt); txt.setText("开始下载"); } public void onDownloadComplete(DownloadManagerAsync manager, Object result) { txt.setText("下载完成"); } public void onDownloadUpdate(DownloadManagerAsync manager, int percent) { txt.setText("下载进度：" + String.valueOf(percent) + "%"); } public void onDownloadError(DownloadManagerAsync manager, Exception e) { txt.setText("下载出错"); } }

Android学习笔记总结的更多相关文章

Android 学习笔记之Volley(七)实现Json数据加载和解析...
学习内容: 1.使用Volley实现异步加载Json数据... Volley的第二大请求就是通过发送请求异步实现Json数据信息的加载,加载Json数据有两种方式,一种是通过获取Json对象,然后 ...
Android学习笔记进阶之在图片上涂鸦(能清屏)
Android学习笔记进阶之在图片上涂鸦(能清屏) 2013-11-19 10:52 117人阅读评论(0) 收藏举报 HandWritingActivity.java package xiaos ...
android学习笔记36——使用原始XML文件
XML文件 android中使用XML文件,需要开发者手动创建res/xml文件夹. 实例如下: book.xml==> <?xml version="1.0" enc ...
Android学习笔记之JSON数据解析
转载:Android学习笔记44:JSON数据解析 JSON(JavaScript Object Notation)是一种轻量级的数据交换格式,采用完全独立于语言的文本格式,为Web应用开发提供了一种 ...
udacity android 学习笔记: lesson 4 part b
udacity android 学习笔记: lesson 4 part b 作者:干货店打杂的 /titer1 /Archimedes 出处:https://code.csdn.net/titer1 ...
Android学习笔记36：使用SQLite方式存储数据
在Android中一共提供了5种数据存储方式,分别为: (1)Files:通过FileInputStream和FileOutputStream对文件进行操作.具体使用方法可以参阅博文<Andro ...
Android学习笔记之Activity详解
1 理解Activity Activity就是一个包含应用程序界面的窗口,是Android四大组件之一.一个应用程序可以包含零个或多个Activity.一个Activity的生命周期是指从屏幕上显示那 ...
Pro Android学习笔记 ActionBar（1）：Home图标区
Pro Android学习笔记(四八):ActionBar(1):Home图标区 2013年03月10日 ⁄ 综合 ⁄ 共 3256字 ⁄ 字号小中大 ⁄ 评论关闭 ActionBar在A ...
【转】Pro Android学习笔记（九八）：BroadcastReceiver（2）：接收器触发通知
文章转载只能用于非商业性质,且不能带有虚拟货币.积分.注册等附加条件.转载须注明出处:http://blog.sina.com.cn/flowingflying或作者@恺风Wei-傻瓜与非傻瓜广播接 ...
【转】 Pro Android学习笔记（九二）：AsyncTask（1）：AsyncTask类
文章转载只能用于非商业性质,且不能带有虚拟货币.积分.注册等附加条件.转载须注明出处:http://blog.csdn.net/flowingflying/ 在Handler的学习系列中,学习了如何h ...

随机推荐

Arduino IDE 添加DHT11传感器第三方库的方法
由于Arduino本身没有DHT 11温湿度传感器的的头文件,单有第三方的库可以给我门使用.方法如下: Step 1:如果你已经下载了最新版的Arduino IDE就可以使用其自带的库管理器和版型管理 ...
Cannot find PHPUnit in include path phpstorm
This is the way to do it without using composer, and using your global phpunit.Phpunit now comes wit ...
PL\SQL学习笔记
注释单行--多行一.declare一般用于做变量的申明.begin 程序体开始执行 end; 程序体结束exception .. dbms_output.put_line('绝对值'||v_ab ...
Delphi XE7,Rad Studio XE7 官方下载（附Delphi XE7破解），更新Update1(转)
源:http://blog.csdn.net/maxwoods/article/details/39024525
我的git常用命令
git add . # 将所有修改过的工作文件提交暂存区 git commit -m ""
未在本地计算机上注册“Microsoft.Ace.OleDB.12.0”
这是异常我的电脑室x86的所以选择x86.
2016"百度之星" - 资格赛（Astar Round1） Problem A
保存前缀乘,询问的时候输出c[ri]/c[li-1]即可,因为是除法,所以计算一下c[li-1]的逆元. #include <stdio.h> #include <math.h> ...
结合Pnotify插件--app-jquery-notify.js
$.NOTIFY = { showSuccess : function (title, text, context) { var opt = { title : title, text : text, ...
mac系统不能使用127.0.0.2的解决方案
英语学得不好,国外这位大神的精彩解释不是特能看的懂.我模仿的试了一下. 解决方案: 1.打开mac终端 2.输入:sudo ifconfig lo0 alias 127.1.1.1 netmask 0 ...
Android获取手机唯一码
大部分安卓手机都可以获取手机唯一码,但是有些手机的厂商却禁止了获取手机唯一码的权限,导致我们不能使用手机唯一码作为标识,但遇到一些必须要填的坑,我们也不能不填,所以使用以下方法来填坑,因此我们使用UU ...

Android学习笔记总结

Android学习笔记总结的更多相关文章

随机推荐

热门专题