在Android应用中使用AlertDialog对话框可以实现哪些功能

package com.example.alertdialog; 
import android.R.bool; 
import android.os.Bundle; 
import android.app.Activity; 
import android.app.AlertDialog; 
import android.app.AlertDialog.Builder; 
import android.app.Dialog; 
import android.content.DialogInterface; 
import android.content.pm.LabeledIntent; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.Toast; 
public class MainActivity extends Activity implements OnClickListener { 
 private Button button1; 
 private Button button2; 
 private Button button3; 
 private Button button4; 
 private Button button5; 
 private int mark=0; 
 private String item[] = { "学生", "工人", "教师", "农民" }; 
 private String multChoice[]={"旅游","电影","运动","读书"}; 
 @Override 
 protected void onCreate(Bundle savedInstanceState) { 
 super.onCreate(savedInstanceState); 
 setContentView(R.layout.activity_main); 
 button1 = (Button) findViewById(R.id.btn_button1); 
 button2 = (Button) findViewById(R.id.btn_button2); 
 button3 = (Button) findViewById(R.id.btn_button3); 
 button4 = (Button) findViewById(R.id.btn_button4); 
 button5 = (Button) findViewById(R.id.btn_button5); 
 button1.setOnClickListener(this); 
 button2.setOnClickListener(this); 
 button3.setOnClickListener(this); 
 button4.setOnClickListener(this); 
 button5.setOnClickListener(this); 
 } 
 @Override 
 public void onClick(View v) { 
 // TODO Auto-generated method stub 
 switch (v.getId()) { 
 //确认对话框 
 case R.id.btn_button1: { 
 AlertDialog.Builder builder = new Builder(this); 
 builder.setIcon(R.drawable.ic_launcher); 
 builder.setTitle("确认对话框"); 
 builder.setMessage("确认退出？"); 
 builder.setPositiveButton("确定", 
  new DialogInterface.OnClickListener() { 
  @Override 
  public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  Toast.makeText(MainActivity.this, "你单击了确定按钮", 
   Toast.LENGTH_SHORT).show(); 
  } 
  }); 
 builder.setNegativeButton("取消", 
  new DialogInterface.OnClickListener() { 
  @Override 
  public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  Toast.makeText(MainActivity.this, "你单击了取消按钮", 
   Toast.LENGTH_SHORT).show(); 
  } 
  }); 
 builder.create(); 
 builder.show(); 
 break; 
 } 
 //列表对话框 
 case R.id.btn_button2: { 
 AlertDialog.Builder builder = new Builder(this); 
 builder.setIcon(R.drawable.ic_launcher); 
 builder.setTitle("职业"); 
 builder.setItems(item, new DialogInterface.OnClickListener() { 
 @Override 
 public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  Toast.makeText(MainActivity.this, "你的职业是" + item[which], 
  Toast.LENGTH_SHORT).show(); 
 } 
 }); 
 builder.create(); 
 builder.show(); 
 break; 
 } 
 //多选对话框 
 case R.id.btn_button3: { 
 final boolean choose[]=new boolean[multChoice.length]; 
 AlertDialog.Builder builder = new Builder(this); 
 builder.setIcon(R.drawable.ic_launcher); 
 builder.setTitle("爱好"); 
 builder.setMultiChoiceItems(multChoice, null, new DialogInterface.OnMultiChoiceClickListener() { 
 @Override 
 public void onClick(DialogInterface dialog, int which, boolean isChecked) { 
  // TODO Auto-generated method stub 
  choose[which]=isChecked; 
 } 
 }); 
 builder.setPositiveButton("确认", new DialogInterface.OnClickListener() { 
 @Override 
 public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  String result=""; 
  for(int i=0;i<multChoice.length;i++){ 
  if(choose[i]){ 
  result+=multChoice[i]+" "; 
  } 
  } 
  Toast.makeText(MainActivity.this, "你的爱好["+result+"]", Toast.LENGTH_SHORT).show(); 
 } 
 }); 
 builder.create(); 
 builder.show(); 
 break; 
 } 
 //单选对话框 
 case R.id.btn_button4: { 
 mark=0; 
 AlertDialog.Builder builder = new Builder(this); 
 builder.setIcon(R.drawable.ic_launcher); 
 builder.setTitle("职业"); 
 builder.setSingleChoiceItems(item, 0, new DialogInterface.OnClickListener() { 
 @Override 
 public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  mark=which; 
 } 
 }); 
 builder.setPositiveButton("确定", 
  new DialogInterface.OnClickListener() { 
  @Override 
  public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  Toast.makeText(MainActivity.this, "你的职业:"+item[mark], Toast.LENGTH_SHORT).show(); 
  } 
  }); 
 builder.create(); 
 builder.show(); 
 break; 
 } 
 //自定义对话框 
 case R.id.btn_button5: { 
 LayoutInflater inflater=LayoutInflater.from(this); 
 View view=inflater.inflate(R.layout.item, null); 
 AlertDialog.Builder builder = new Builder(this); 
 builder.setIcon(R.drawable.ic_launcher); 
 builder.setTitle("自定义对话框"); 
 builder.setView(view); 
 builder.setNeutralButton("普通按钮", new DialogInterface.OnClickListener() { 
 @Override 
 public void onClick(DialogInterface dialog, int which) { 
  // TODO Auto-generated method stub 
  Toast.makeText(MainActivity.this,"我是自定义的对话框哦",Toast.LENGTH_SHORT).show(); 
 } 
 }); 
 builder.create(); 
 builder.show(); 
 break; 
 } 
 } 
 } 
} 

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 xmlns:tools="http://schemas.android.com/tools" 
 android:layout_width="match_parent" 
 android:layout_height="match_parent" 
android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" 
 tools:context=".MainActivity" > 
 <LinearLayout 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:orientation="vertical" > 
 <Button 
 android:id="@+id/btn_button1" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="确认对话框" /> 
 <Button 
 android:id="@+id/btn_button2" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="列表对话框" /> 
 <Button 
 android:id="@+id/btn_button3" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="多选对话框" /> 
 <Button 
 android:id="@+id/btn_button4" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="单选对话框" /> 
 <Button 
 android:id="@+id/btn_button5" 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="自定义对话框" /> 
 </LinearLayout> 
</RelativeLayout> 

<&#63;xml version="1.0" encoding="utf-8"&#63;> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
 android:layout_width="match_parent" 
 android:layout_height="match_parent" 
 android:orientation="vertical" > 
 <ImageView 
 android:layout_width="wrap_content" 
 android:layout_height="wrap_content" 
 android:scaleType="fitCenter" 
 android:src="@drawable/icon" 
 /> 
 <TextView 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:text="我是自定义的对话框" 
 /> 
</LinearLayout>