AlertDialog详解

原文出处

 AlertDialog的构造方法全部是Protected的，所以不能直接通过new一个AlertDialog来创建出一个AlertDialog。

要创建一个AlertDialog，就要用到AlertDialog.Builder中的create()方法。

使用AlertDialog.Builder创建对话框需要了解以下几个方法：

setTitle ：为对话框设置标题
setIcon ：为对话框设置图标
setMessage：为对话框设置内容
setView ： 给对话框设置自定义样式
setItems ：设置对话框要显示的一个list，一般用于显示几个命令时
setMultiChoiceItems ：用来设置对话框显示一系列的复选框
setNeutralButton   ：普通按钮

setPositiveButton  ：给对话框添加"Yes"按钮
setNegativeButton ：对话框添加"No"按钮
create ： 创建对话框
show ：显示对话框
一、简单的AlertDialog

下面，创建一个简单的ALertDialog并显示它：

[java]  packagecom.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
import android.os.Bundle; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  
    
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("对话框的标题"). 
               setMessage("对话框的内容"). 
               setIcon(R.drawable.ic_launcher).  
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.os.Bundle;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 
 
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  DialogalertDialog = new AlertDialog.Builder(this). 
    setTitle("对话框的标题").
    setMessage("对话框的内容").
    setIcon(R.drawable.ic_launcher). 
    create();
   alertDialog.show();
  }
}运行结果如下：

 

   二、带按钮的AlertDialog

上面的例子很简单，下面我们在这个AlertDialog上面加几个Button，实现删除操作的提示对话框

[java] package com.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
importandroid.content.DialogInterface;  
import android.os.Bundle; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  
    
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("确定删除？"). 
               setMessage("您确定删除该条信息吗？"). 
               setIcon(R.drawable.ic_launcher).  
               setPositiveButton("确定", new DialogInterface.OnClickListener(){  

                                        @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               setNegativeButton("取消", new DialogInterface.OnClickListener(){  

                                        @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               setNeutralButton("查看详情", new DialogInterface.OnClickListener(){  

                                        @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
importandroid.content.DialogInterface; 
importandroid.os.Bundle;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 
 
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  DialogalertDialog = new AlertDialog.Builder(this). 
    setTitle("确定删除？").
    setMessage("您确定删除该条信息吗？").
    setIcon(R.drawable.ic_launcher). 
    setPositiveButton("确定", new DialogInterface.OnClickListener(){ 

          @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    setNegativeButton("取消", new DialogInterface.OnClickListener(){ 

          @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    setNeutralButton("查看详情", new DialogInterface.OnClickListener(){ 

          @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    create();
   alertDialog.show();
  }
}在这个例子中，我们定义了三个按钮，分别是"Yes"按钮，"No"按钮以及一个普通按钮，每个按钮都有onClick事件，TODO的地方可以放点了按钮之后想要做的一些处理

看一下运行结果：

 可以看到三个按钮添加到了AlertDialog上，三个没有添加事件处理的按钮，点了只是关闭对话框，没有任何其他操作。

 

 

 

   三、类似ListView的AlertDialog
用setItems(CharSequence[] items, final OnClickListenerlistener)方法来实现类似ListView的AlertDialog

第一个参数是要显示的数据的数组，第二个参数是点击某个item的触发事件

[java] package com.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
importandroid.content.DialogInterface;  
import android.os.Bundle; 
import android.widget.Toast; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  
    
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉"}; 

        Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("你喜欢吃哪种水果？"). 
               setIcon(R.drawable.ic_launcher)  
               .setItems(arrayFruit, new DialogInterface.OnClickListener(){  

                     @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       Toast.makeText(Dialog_AlertDialogDemoActivity.this,arrayFruit[which],Toast.LENGTH_SHORT).show();  
                   } 
               }). 
               setNegativeButton("取消", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
importandroid.content.DialogInterface; 
importandroid.os.Bundle;
import android.widget.Toast;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 
 
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  final String[] arrayFruit = newString[] { "苹果", "橘子", "草莓", "香蕉" };

  DialogalertDialog = new AlertDialog.Builder(this). 
    setTitle("你喜欢吃哪种水果？").
    setIcon(R.drawable.ic_launcher) 
    .setItems(arrayFruit, new DialogInterface.OnClickListener(){ 

      @Override
     public void onClick(DialogInterface dialog, int which) {
      Toast.makeText(Dialog_AlertDialogDemoActivity.this,arrayFruit[which], Toast.LENGTH_SHORT).show(); 
     }
    }).
    setNegativeButton("取消", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    create();
   alertDialog.show();
  }
}运行结果如下：

 

 

 

    四、类似RadioButton的AlertDialog
用setSingleChoiceItems(CharSequence[] items, int checkedItem, finalOnClickListenerlistener)方法来实现类似RadioButton的AlertDialog

第一个参数是要显示的数据的数组，第二个参数是初始值（初始被选中的item），第三个参数是点击某个item的触发事件

在这个例子里面我们设了一个selectedFruitIndex用来记住选中的item的index

[java] package com.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
importandroid.content.DialogInterface;  
import android.os.Bundle; 
import android.widget.Toast; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  

        private int selectedFruitIndex = 0; 

         
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉"}; 

        Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("你喜欢吃哪种水果？"). 
               setIcon(R.drawable.ic_launcher)  
               .setSingleChoiceItems(arrayFruit, 0, newDialogInterface.OnClickListener(){  

                     @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       selectedFruitIndex = which; 
                   } 
               }). 
               setPositiveButton("确认", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       Toast.makeText(Dialog_AlertDialogDemoActivity.this,arrayFruit[selectedFruitIndex],Toast.LENGTH_SHORT).show();  
                   } 
               }). 
               setNegativeButton("取消", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
importandroid.content.DialogInterface; 
importandroid.os.Bundle;
import android.widget.Toast;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 

   private int selectedFruitIndex= 0;

  
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  final String[] arrayFruit = newString[] { "苹果", "橘子", "草莓", "香蕉" };

  DialogalertDialog = new AlertDialog.Builder(this). 
    setTitle("你喜欢吃哪种水果？").
    setIcon(R.drawable.ic_launcher) 
    .setSingleChoiceItems(arrayFruit, 0, newDialogInterface.OnClickListener() { 

      @Override
     public void onClick(DialogInterface dialog, int which) {
      selectedFruitIndex = which;
     }
    }).
    setPositiveButton("确认", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      Toast.makeText(Dialog_AlertDialogDemoActivity.this,arrayFruit[selectedFruitIndex],Toast.LENGTH_SHORT).show(); 
     }
    }).
    setNegativeButton("取消", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    create();
   alertDialog.show();
  }
}

运行结果如下：

 

  五、类似CheckBox的AlertDialog
用setMultiChoiceItems(CharSequence[]items, boolean[] checkedItems, final OnMultiChoiceClickListenerlistener)方法来实现类似CheckBox的AlertDialog 
第一个参数是要显示的数据的数组，第二个参数是选中状态的数组，第三个参数是点击某个item的触发事件

[java] package com.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
importandroid.content.DialogInterface;  
import android.os.Bundle; 
import android.widget.Toast; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  
    
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        final String[] arrayFruit = new String[] { "苹果", "橘子", "草莓", "香蕉"}; 
       final boolean[] arrayFruitSelected = new boolean[] {true, true,false, false}; 

        Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("你喜欢吃哪种水果？"). 
               setIcon(R.drawable.ic_launcher)  
               .setMultiChoiceItems(arrayFruit, arrayFruitSelected, newDialogInterface.OnMultiChoiceClickListener(){  

                                        @Override 
                   public void onClick(DialogInterface dialog, int which, booleanisChecked) { 
                       arrayFruitSelected[which] = isChecked; 
                   } 
               }). 
               setPositiveButton("确认", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       StringBuilder stringBuilder = newStringBuilder(); 
                       for (int i = 0; i< arrayFruitSelected.length; i++){  
                           if (arrayFruitSelected[i] == true) 
                           { 
                               stringBuilder.append(arrayFruit[i] +"、");  
                           } 
                       } 
                       Toast.makeText(Dialog_AlertDialogDemoActivity.this,stringBuilder.toString(),Toast.LENGTH_SHORT).show();  
                   } 
               }). 
               setNegativeButton("取消", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
importandroid.content.DialogInterface; 
importandroid.os.Bundle;
import android.widget.Toast;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 
 
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  final String[] arrayFruit = newString[] { "苹果", "橘子", "草莓", "香蕉" };
   final boolean[]arrayFruitSelected = new boolean[] {true, true, false, false};

  DialogalertDialog = new AlertDialog.Builder(this). 
    setTitle("你喜欢吃哪种水果？").
    setIcon(R.drawable.ic_launcher) 
    .setMultiChoiceItems(arrayFruit, arrayFruitSelected, newDialogInterface.OnMultiChoiceClickListener() { 

          @Override
     public void onClick(DialogInterface dialog, int which, booleanisChecked) {
      arrayFruitSelected[which] = isChecked;
     }
    }).
    setPositiveButton("确认", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      StringBuilder stringBuilder = new StringBuilder();
      for (int i = 0; i< arrayFruitSelected.length; i++){ 
       if (arrayFruitSelected[i] == true)
       {
        stringBuilder.append(arrayFruit[i] + "、"); 
       }
      }
      Toast.makeText(Dialog_AlertDialogDemoActivity.this,stringBuilder.toString(),Toast.LENGTH_SHORT).show(); 
     }
    }).
    setNegativeButton("取消", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    create();
   alertDialog.show();
  }
}运行结果如下：

 

 

   六、自定义View的AlertDialog
有时候我们不能满足系统自带的AlertDialog风格，就比如说我们要实现一个Login画面，有用户名和密码，这时我们就要用到自定义View的AlertDialog

先创建Login画面的布局文件

[html]< ?xml version="1.0"encoding="utf-8"?> 
< LinearLayout xmlns:android=" http://schemas.android.com/apk/res/android " 
   android:layout_width="fill_parent"  
   android:layout_height="fill_parent"  
   android:orientation="vertical">  

    <LinearLayout 
       android:layout_width="fill_parent"  
       android:layout_height="wrap_content"  
       android:gravity="center" > 

        <TextView 
           android:layout_width="0dip"  
           android:layout_height="wrap_content"  
           android:layout_weight="1" 
           android:text="@string/user"/>  

        <EditText 
           android:layout_width="0dip"  
           android:layout_height="wrap_content"  
           android:layout_weight="1" /> 
   </LinearLayout> 

    <LinearLayout 
       android:layout_width="fill_parent"  
       android:layout_height="wrap_content"  
       android:gravity="center" > 

        <TextView 
           android:layout_width="0dip"  
           android:layout_height="wrap_content"  
           android:layout_weight="1" 
           android:text="@string/passward"/>  

        <EditText 
           android:layout_width="0dip"  
           android:layout_height="wrap_content"  
           android:layout_weight="1" /> 
   </LinearLayout> 

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

   <LinearLayout
       android:layout_width="fill_parent" 
       android:layout_height="wrap_content" 
       android:gravity="center" >

       <TextView
           android:layout_width="0dip" 
           android:layout_height="wrap_content" 
           android:layout_weight="1"
           android:text="@string/user" />

       <EditText
           android:layout_width="0dip" 
           android:layout_height="wrap_content" 
           android:layout_weight="1" />
   </LinearLayout>

   <LinearLayout
       android:layout_width="fill_parent" 
       android:layout_height="wrap_content" 
       android:gravity="center" >

       <TextView
           android:layout_width="0dip" 
           android:layout_height="wrap_content" 
           android:layout_weight="1"
           android:text="@string/passward" />

       <EditText
           android:layout_width="0dip" 
           android:layout_height="wrap_content" 
           android:layout_weight="1" />
   </LinearLayout>

然后在Activity里面把Login画面的布局文件添加到AlertDialog上

[java] package com.tianjf; 

  importandroid.app.Activity; 
import android.app.AlertDialog; 
import android.app.Dialog; 
importandroid.content.DialogInterface;  
import android.os.Bundle; 
importandroid.view.LayoutInflater;  
import android.view.View; 

 public class Dialog_AlertDialogDemoActivity extends Activity{  
    
   @Override 
    public voidonCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState);  
       setContentView(R.layout.main);  

        // 取得自定义View  
       LayoutInflater layoutInflater =LayoutInflater.from(this);  
       View myLoginView = layoutInflater.inflate(R.layout.login,null);  

                Dialog alertDialog = newAlertDialog.Builder(this).  
               setTitle("用户登录"). 
               setIcon(R.drawable.ic_launcher).  
               setView(myLoginView). 
               setPositiveButton("登录", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               setNegativeButton("取消", new DialogInterface.OnClickListener(){  

                    @Override 
                   public void onClick(DialogInterface dialog, int which){ 
                       // TODO Auto-generated methodstub  
                   } 
               }). 
               create(); 
       alertDialog.show(); 
   } 
} 
package com.tianjf;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
importandroid.content.DialogInterface; 
import android.os.Bundle;
importandroid.view.LayoutInflater; 
importandroid.view.View;

publicclass Dialog_AlertDialogDemoActivity extends Activity{ 
 
  @Override
  public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main);

  // 取得自定义View
  LayoutInflater layoutInflater =LayoutInflater.from(this); 
  View myLoginView = layoutInflater.inflate(R.layout.login,null); 

    Dialog alertDialog = newAlertDialog.Builder(this). 
    setTitle("用户登录").
    setIcon(R.drawable.ic_launcher). 
    setView(myLoginView).
    setPositiveButton("登录", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    setNegativeButton("取消", new DialogInterface.OnClickListener(){

     @Override
     public void onClick(DialogInterface dialog, int which) {
      // TODO Auto-generated method stub
     }
    }).
    create();
   alertDialog.show();
  }
}运行结果如下：