android监听返回按钮事件，android监听按钮,用户在点击手机的返回按钮

android监听返回按钮事件，android监听按钮,用户在点击手机的返回按钮

用户在点击手机的返回按钮时，默认是推出当前的activty，但是有时用户不小心按到返回，所以需要给用户一个提示，这就需要重写onkeydown事件：

[Java]代码

@Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.main);     }     protected void dialog() {         AlertDialog.Builder builder = new Builder(HanderTestActivty.this);         builder.setMessage("确定要退出吗?");         builder.setTitle("提示");         builder.setPositiveButton("确认",                 new android.content.DialogInterface.OnClickListener() {                     @Override                     public void onClick(DialogInterface dialog, int which) {                         dialog.dismiss();                         HanderTestActivty.this.finish();                     }                 });         builder.setNegativeButton("取消",                 new android.content.DialogInterface.OnClickListener() {                     @Override                     public void onClick(DialogInterface dialog, int which) {                         dialog.dismiss();                     }                 });         builder.create().show();     }     @Override     public boolean onKeyDown(int keyCode, KeyEvent event) {         if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {             dialog();             return false;         }         return false;     }