如何取消我的Android警報對話框？

Question

這是我的警報：

new AlertDialog.Builder(Activity.this)
    .setMessage("You have unsaved text. Are you sure you want to leave?")
    .setCancelable(true)
    .setNegativeButton("Leave", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int id) 
        {
            finish();
        }
    })
    .setPositiveButton("Stay", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {}
    }).show();

請注意我如何允許警報取消： .setCancelable(true)

一旦用戶按下后退按鈕取消警報，我該如何運行一些代碼？

Answer 1

根據Android網站上的AlertDialog.Builder文檔，您可以使用setOnCancelListener（DialogInterface.OnCancelListener onCancelListener）方法來處理取消對話框的時間。

.setOnCancelListener(new DialogInterface.OnCancelListener() {
    @Override
    public void onCancel(DialogInterface dialog) 
    {
        // do what you need when the dialog is cancelled
    }
})

所以，你的代碼將改為：

new AlertDialog.Builder(Activity.this)
    .setMessage("You have unsaved text. Are you sure you want to leave?")
    .setCancelable(true)
    .setOnCancelListener(new DialogInterface.OnCancelListener() {
        @Override
        public void onCancel(DialogInterface dialog) 
        {
            // do what you need when the dialog is cancelled
        }
    })
    .setNegativeButton("Leave", new DialogInterface.OnClickListener() { 
        public void onClick(DialogInterface dialog, int id) 
        {
            finish();
        }
    })
    .setPositiveButton("Stay", new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog, int which) {}
    }).show();