[2017-7-28]Android Learning Day6

常用控件

1. Spinner

2. DatePickerDialog

3. TimePickerDiaog

4. RadioButton

5. CheckBox

spinner（下拉菜单）

<Spinner
        android:id="@+id/spinner"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

 public class MainActivity extends AppCompatActivity {
 
     private Spinner s;
     private String[] dataSource = new String[]{"a1","b2","c3"};
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
 
         s = (Spinner) findViewById(R.id.spinner);
         //设置一个Adapter
         s.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, dataSource));
 　　　　　//sOnSe                         OnIt
         s.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
             @Override
             public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                 //在这里写监听事件
　　　　　　　　　　　　System.out.println("用户选择的是"+dataSource[position]);
             }
 
             @Override
             public void onNothingSelected(AdapterView<?> parent) {
 　　　　　　　　　　//不写
             }
         });
     }
 }

DatePickerDialog（日期选择器）

<Button
    android:id="@+id/button"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="选择日期" />

 public class ChooseDate extends AppCompatActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_choose_date);
         slove();
     }
 
     public void slove() {
         findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 new DatePickerDialog(ChooseDate.this, new DatePickerDialog.OnDateSetListener() {
                     @Override
                     public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
                         String chooseDate = String.format("%04d-%02d-%02d",year,month+1,dayOfMonth);//"%04d"总长度4位，不够用0补齐
                         ((Button) findViewById(R.id.button)).setText(chooseDate);
                     }
                 },2000,0,1).show();//要注意月份是从0~11
             }
         });
     }
 }

TimePickerDialog（时间选择器）

这个就和日期选择器很像了

<Button
        android:id="@+id/button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="选择时间" />

 public class ChooseTime extends AppCompatActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_choose_date);
         slove();
     }
 
     public void slove() {
         findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 new TimePickerDialog(ChooseTime.this, new TimePickerDialog.OnTimeSetListener() {
                     @Override
                     public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
                         String chooseTime = String.format("%02d:%02d",hourOfDay,minute);
                         ((Button) findViewById(R.id.button)).setText(chooseTime);
                     }
                 },0,0,true).show();//True是否使用24小时制
             }
         });
     }
 }

RadioButton（单选框）

这个要注意的是，单选按钮不能单独存在，要放在RadioGroup里

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical">
     <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical"
         android:layout_weight="1">
 
         <TextView
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:layout_marginBottom="10dp"
             android:textSize="18sp"
             android:text="世界上最大的海洋是？"/>
 
         <RadioGroup
             android:layout_width="match_parent"
             android:layout_height="wrap_content" >
 
             <RadioButton
                 android:id="@+id/rbA"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:textSize="16sp"
                 android:text="A.太平洋" />
 
             <RadioButton
                 android:id="@+id/rbB"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content"
                 android:textSize="16sp"
                 android:text="B.北冰洋" />
         </RadioGroup>
 
     </LinearLayout>
 
     <Button
         android:id="@+id/chooseOne"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="提交"/>
 
 </LinearLayout>

 public class ChooseSingle extends AppCompatActivity {
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_choose_single);
         slove();
     }
 
     private void slove() {
         findViewById(R.id.chooseOne).setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 RadioButton rb = (RadioButton) findViewById(R.id.rbA);
                 if(rb.isChecked()) {
                     Toast.makeText(ChooseSingle.this, "正确", Toast.LENGTH_SHORT).show();
                 }
                 else {
                     Toast.makeText(ChooseSingle.this, "错误", Toast.LENGTH_SHORT).show();
                 }
             }
         });
     }
 }

CheckBox（多选框）

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical">
 
     <TextView
         android:id="@+id/tv1"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="你喜欢喝什么饮料？" />
 
     <CheckBox
         android:id="@+id/cb1"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="冰峰" />
 
     <CheckBox
         android:id="@+id/cb2"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="果啤" />
 
     <CheckBox
         android:id="@+id/cb3"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="雪碧" />
 
     <TextView
         android:id="@+id/tv2"
         android:layout_width="match_parent"
         android:layout_height="wrap_content" />
 </LinearLayout>

 package com.liwenchi.myapplication;
 
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 import android.view.View;
 import android.widget.CheckBox;
 import android.widget.CompoundButton;
 import android.widget.TextView;
 
 public class MainActivity extends AppCompatActivity {
 
     private CheckBox cb1,cb2,cb3;
     private TextView tv;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         slove();
     }
 
     public void slove() {
         cb1 = (CheckBox) findViewById(R.id.cb1);
         cb2 = (CheckBox) findViewById(R.id.cb2);
         cb3 = (CheckBox) findViewById(R.id.cb3);
         tv = (TextView) findViewById(R.id.tv2);
         cb1.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
             @Override
             public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 onChanged();
             }
         });
         cb2.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
             @Override
             public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 onChanged();
             }
         });
         cb3.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
             @Override
             public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                 onChanged();
             }
         });
     }
 
     public void onChanged() {
         String s = "我喜欢";
         if(cb1.isChecked()) {
             s += ","+cb1.getText();
         }
         if(cb2.isChecked()) {
             s += ","+cb2.getText();
         }
         if(cb3.isChecked()) {
             s += ","+cb3.getText();
         }
         tv.setText(s);
     }
 }