[Android]詢問對話框

 這個例子是在主頁面按返回上頁鍵會跳出對話框，確定後離開程式

以下是程式碼：

@Overridepublic boolean onKeyDown(int keyCode, KeyEvent event)
{
    if (keyCode == KeyEvent.KEYCODE_BACK && this.getTitle().equals("") )
    {
        // 創建退出對話框        AlertDialog.Builder d = new AlertDialog.Builder(this)
                .setMessage("確定要退出嗎")
                .setCancelable(false);
        d.setPositiveButton("確定", new DialogInterface.OnClickListener() {
            @Override            public void onClick(DialogInterface dialog, int which) {
                finish();            }
        });        d.setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override            public void onClick(DialogInterface dialog, int which) {

            }
        });        d.show();    }else if(keyCode == KeyEvent.KEYCODE_DEL){

    }else{
        finish();    }
    return false;}