怎样控制界面控件之进度条(ProgressBar)功能

一、基础知识:

1.ProgressBar在界面文件XML中的布局:

[html]
<progressBar android:id="@+id/progressbar_updown" 
        android:layout_width="200dp"  
        android:layout_height="wrap_content" 
        style="?android:attr/progressBarStyleHorizontal" 
        android:layout_gravity="center_vertical"  
        android:max="100" 
        android:progress="50" 
        android:secondaryProgress="70"    >

<progressBar android:id="@+id/progressbar_updown"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_gravity="center_vertical"
        android:max="100"
        android:progress="50"
        android:secondaryProgress="70"    >

[plain]
style="?android:attr/progressBarStyleHorizontal"    设置风格为长形  
android:max="100"    最大进度值为100  
android:progress="50"   初始化的进度值  
android:secondaryProgress="70" 初始化的底层第二个进度值  
android:layout_gravity="center_vertical"    垂直居中

style="?android:attr/progressBarStyleHorizontal"    设置风格为长形
android:max="100"    最大进度值为100
android:progress="50"   初始化的进度值
android:secondaryProgress="70" 初始化的底层第二个进度值
android:layout_gravity="center_vertical"    垂直居中

2.ProgressBar在代码文件(.java)中的控制使用:

[java]
private ProgressBar myProgressBar; 
//定义ProgressBar  
 
myProgressBar = (ProgressBar) findViewById(R.id.progressbar_updown); 
//ProgressBar通过ID来从XML中获取  
 
myProgressBar.incrementProgressBy(5); 
//ProgressBar进度值增加5  
 
myProgressBar.incrementProgressBy(-5); 
//ProgressBar进度值减少5  
 
myProgressBar.incrementSecondaryProgressBy(5); 
//ProgressBar背后的第二个进度条 进度值增加5  
 
myProgressBar.incrementSecondaryProgressBy(-5); 
//ProgressBar背后的第二个进度条 进度值减少5

private ProgressBar myProgressBar;
//定义ProgressBar

myProgressBar = (ProgressBar) findViewById(R.id.progressbar_updown);
//ProgressBar通过ID来从XML中获取

myProgressBar.incrementProgressBy(5);
//ProgressBar进度值增加5

myProgressBar.incrementProgressBy(-5);
//ProgressBar进度值减少5

myProgressBar.incrementSecondaryProgressBy(5);
//ProgressBar背后的第二个进度条 进度值增加5

myProgressBar.incrementSecondaryProgressBy(-5);
//ProgressBar背后的第二个进度条 进度值减少5

3.XML重要属性

android:progressBarStyle：默认进度条样式

android:progressBarStyleHorizontal：水平样式

4.重要方法

[plain]
getMax()：返回这个进度条的范围的上限 
 
getProgress()：返回进度 
 
getSecondaryProgress()：返回次要进度 
 
incrementProgressBy(int diff)：指定增加的进度 
 
isIndeterminate()：指示进度条是否在不确定模式下 
 
setIndeterminate(boolean indeterminate)：设置不确定模式下 
 
setVisibility(int v)：设置该进度条是否可视

getMax()：返回这个进度条的范围的上限

getProgress()：返回进度

getSecondaryProgress()：返回次要进度

incrementProgressBy(int diff)：指定增加的进度

isIndeterminate()：指示进度条是否在不确定模式下

setIndeterminate(boolean indeterminate)：设置不确定模式下

setVisibility(int v)：设置该进度条是否可视

二、代码展示:

1."Activity_09\src\yan\activity_09\MainActivity.java"

[java]
package yan.activity_09; 
 
import android.os.Bundle; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.ProgressBar; 
import android.app.Activity; 
 
public class MainActivity extends Activity { 
    // 声明变量  
    private ProgressBar firstBar = null; 
    private ProgressBar secondBar = null; 
    private Button myButton = null; 
    private int progress_vol = 0; 
     
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState); 
        setContentView(R.layout.main); 
         
        //映射控件ID到变量  
        firstBar = (ProgressBar)findViewById(R.id.firstBar); 
        secondBar = (ProgressBar)findViewById(R.id.secondBar); 
        myButton = (Button)findViewById(R.id.myButton); 
         
         
        myButton.setOnClickListener(new ButtonListenr()); 
    } 
     
    class ButtonListenr implements OnClickListener{ 
 
        @Override 
        public void onClick(View v) { 
            // TODO Auto-generated method stub  
            if(0 == progress_vol) 
            { 
                // 设置进度条的最大值  
                firstBar.setMax(200); 
                // 设置进度条为可见的状态  
                firstBar.setVisibility(View.VISIBLE); 
                secondBar.setVisibility(View.VISIBLE); 
            }else if(progress_vol < firstBar.getMax()){ 
                // 设置主进度条的当前值  
                firstBar.setProgress(progress_vol); 
                // 设置第二进度条的当前值  
                firstBar.setSecondaryProgress(progress_vol+10); 
                // 默认的进度条是无法显示进行的状态的  
                //secondBar.setProgress(progress_vol);  
            }else{ 
                // 设置进度条为不可见的状态  
                firstBar.setVisibility(View.GONE); 
                secondBar.setVisibility(View.GONE); 
            } 
            progress_vol +=10; 
        } 
         
    } 
}

package yan.activity_09;

import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.app.Activity;

public class MainActivity extends Activity {
 // 声明变量
 private ProgressBar firstBar = null;
 private ProgressBar secondBar = null;
 private Button myButton = null;
 private int progress_vol = 0;
 
 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  
  //映射控件ID到变量
  firstBar = (ProgressBar)findViewById(R.id.firstBar);
  secondBar = (ProgressBar)findViewById(R.id.secondBar);
  myButton = (Button)findViewById(R.id.myButton);
  
  
  myButton.setOnClickListener(new ButtonListenr());
 }
 
 class ButtonListenr implements OnClickListener{

@Override
  public void onClick(View v) {
   // TODO Auto-generated method stub
   if(0 == progress_vol)
   {
    // 设置进度条的最大值
    firstBar.setMax(200);
    // 设置进度条为可见的状态
    firstBar.setVisibility(View.VISIBLE);
    secondBar.setVisibility(View.VISIBLE);
   }else if(progress_vol < firstBar.getMax()){
    // 设置主进度条的当前值
    firstBar.setProgress(progress_vol);
    // 设置第二进度条的当前值
    firstBar.setSecondaryProgress(progress_vol+10);
    // 默认的进度条是无法显示进行的状态的
    //secondBar.setProgress(progress_vol);
   }else{
    // 设置进度条为不可见的状态
    firstBar.setVisibility(View.GONE);
    secondBar.setVisibility(View.GONE);
   }
   progress_vol +=10;
  }
  
 }
}

2."Activity_09\res\layout\main.xml"

[html]
<?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:background="#00aaaa"   
    >   
   <TextView 
        android:id="@+id/firstText"   
        android:text="@string/hello_world"   
        android:gravity="center_vertical"   
        android:textSize="15pt"   
        android:background="#aa0000"   
        android:layout_width="fill_parent"   
        android:layout_height="wrap_content"   
        android:singleLine="true"/>   
<ProgressBar 
    android:id="@+id/firstBar" 
    style="?android:attr/progressBarStyleHorizontal" 
    android:layout_width="200dp" 
    android:layout_height="wrap_content" 
    android:visibility="gone" 
    /> 
<ProgressBar 
    android:id="@+id/secondBar" 
    style="?android:attr/progressBarStyle" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:visibility="gone" 
    /> 
<Button 
    android:id="@+id/myButton" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="begin" 
    /> 
</LinearLayout>

<?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:background="#00aaaa" 
    > 
   <TextView
  android:id="@+id/firstText" 
  android:text="@string/hello_world" 
  android:gravity="center_vertical" 
  android:textSize="15pt" 
  android:background="#aa0000" 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
  android:singleLine="true"/> 
<ProgressBar
    android:id="@+id/firstBar"
    style="?android:attr/progressBarStyleHorizontal"
    android:layout_width="200dp"
    android:layout_height="wrap_content"
    android:visibility="gone"
    />
<ProgressBar
    android:id="@+id/secondBar"
    style="?android:attr/progressBarStyle"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:visibility="gone"
    />
<Button
    android:id="@+id/myButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="begin"
    />
</LinearLayout> 
3."Activity_09\res\values\strings.xml"

[html]
<?xml version="1.0" encoding="utf-8"?> 
<resources> 
 
    <string name="app_name">Activity_09</string> 
    <string name="hello_world">Hello world!</string> 
    <string name="menu_settings">Settings</string> 
 
</resources>

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

<string name="app_name">Activity_09</string>
    <string name="hello_world">Hello world!</string>
    <string name="menu_settings">Settings</string>

</resources>