android监听返回按钮事件

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，实现的效果如下：




实现代码如下：

@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;

}