Android 弹出对话框Dialog

package Rw.Dialog;      import Android.app.Activity;   import android.app.AlertDialog;   import android.app.ProgressDialog;   import android.content.DialogInterface;   import android.content.Intent;   import android.os.Bundle;   import android.view.LayoutInflater;   import android.view.View;   import android.view.View.OnClickListener;   import android.widget.Button;   import android.widget.Toast;      public class Dialog01Activity extends Activity {           private Button button1,button2,button3,button4,button6,button7;       ProgressDialog progressDialog=null;       public void onCreate(Bundle savedInstanceState) {           super.onCreate(savedInstanceState);           setContentView(R.layout.main);           button1=(Button)findViewById(R.id.button1);           button2=(Button)findViewById(R.id.button2);           button3=(Button)findViewById(R.id.button3);           button4=(Button)findViewById(R.id.button4);           button6=(Button)findViewById(R.id.button6);           button7=(Button)findViewById(R.id.button7);                button1.setOnClickListener(new ButtonListener());           button2.setOnClickListener(new ButtonListener());           button3.setOnClickListener(new ButtonListener());           button4.setOnClickListener(new ButtonListener());           button6.setOnClickListener(new ButtonListener());           button7.setOnClickListener(new ButtonListener());       }             class ButtonListener implements OnClickListener{              @Override           public void onClick(View v) {                final String[] itemStrings={"AA","BB","CC","DD"};               // TODO Auto-generated method stub                switch (v.getId()) {               case R.id.button1:                    AlertDialog.Builder dialog=new AlertDialog.Builder(Dialog01Activity.this);                      dialog.setTitle("Dialog").setIcon(android.R.drawable.ic_dialog_info).setMessage("弹出框").setPositiveButton("确定", new DialogInterface.OnClickListener() {                                              @Override                       public void onClick(DialogInterface dialog, int which) {                           //转跳到另外一个Activity                            // TODO Auto-generated method stub                            Intent intent=new Intent();                           intent.setClass(getApplicationContext(), list.class);                           startActivity(intent);                       }                   }).setNegativeButton("取消", new DialogInterface.OnClickListener() {                                                                     public void onClick(DialogInterface dialog, int which) {                           // TODO Auto-generated method stub                            dialog.cancel();//取消弹出框                        }                   }).create().show();                   break;               case R.id.button2:                                      AlertDialog.Builder builder=new AlertDialog.Builder(Dialog01Activity.this);                   builder.setTitle("LIST").setIcon(android.R.drawable.ic_lock_lock).setItems(itemStrings, new DialogInterface.OnClickListener() {                                              @Override                       public void onClick(DialogInterface dialog, int which) {                           // TODO Auto-generated method stub                        Toast.makeText(getApplicationContext(), "你点击的是"+itemStrings[which], Toast.LENGTH_LONG).show();                         }                   }).create().show();                   break;               case R.id.button3:                                      AlertDialog.Builder builder1=new AlertDialog.Builder(Dialog01Activity.this);                   builder1.setTitle("LIST").setIcon(android.R.drawable.ic_lock_lock).setSingleChoiceItems(itemStrings,-1, new DialogInterface.OnClickListener() {                                              @Override                       public void onClick(DialogInterface dialog, int which) {                           // TODO Auto-generated method stub                        Toast.makeText(getApplicationContext(), "你点击的是"+itemStrings[which], Toast.LENGTH_LONG).show();                                                }                   }).create().show();                   builder1.setCancelable(true);                   break;                   case R.id.button4:                       progressDialog=ProgressDialog.show(Dialog01Activity.this, "下载", "下载中.....",true);                       progressDialog.setCancelable(true);//当点击按钮返回的时候Dialog消失                        //progressDialog.dismiss();                        break;                                          case R.id.button6:                       LayoutInflater inflater=(LayoutInflater)getApplicationContext().getSystemService(LAYOUT_INFLATER_SERVICE);                       View view=inflater.inflate(R.layout.style, null);                       AlertDialog.Builder builder2=new AlertDialog.Builder(Dialog01Activity.this);                       builder2.setView(view);                       builder2.setTitle("QQ2011").setPositiveButton("确定", new DialogInterface.OnClickListener() {                                                      @Override                           public void onClick(DialogInterface dialog, int which) {                               // TODO Auto-generated method stub                                dialog.cancel();                           }                       }).create().show();                                             break;                   case R.id.button7:                       Dialog01Activity.this.finish();                           break;               default:                   break;               }           }                  }   }