1. protected void dialog() {
2.         AlertDialog.Builder builder = new Builder(AccoutList.this);
3.         builder.setMessage("确定要退出吗?");
4.         builder.setTitle("提示");
5.         builder.setPositiveButton("确认",
6.         new android.content.DialogInterface.OnClickListener() {
7.             @Override
8.             public void onClick(DialogInterface dialog, int which) {
9.                 dialog.dismiss();
10.                 //AccoutList.this.finish();
11.                 //System.exit(1);
12.                 android.os.Process.killProcess(android.os.Process.myPid());
13.             }
14.         });
15.         builder.setNegativeButton("取消",
16.         new android.content.DialogInterface.OnClickListener() {
17.             @Override
18.             public void onClick(DialogInterface dialog, int which) {
19.                 dialog.dismiss();
20.             }
21.         });
22.         builder.create().show();
23.     }

from:http://blog.csdn.net/jumping_android/article/details/7571309