[Android] Dialog錯誤顯示彈跳訊息，簡易版

CustomDialog alertDialog = null;
public void showAlert(String message) {
try {
if (activity != null) {
if (alertDialog != null && alertDialog.isShowing()) {
alertDialog.appendMessage(message);
} else {
alertDialog = new CustomDialog.Builder(activity).setTitle(getString(R.string.text_alert))
.setMessage(message).setCenterButton(getString(R.string.btn_confirm), null).create();
if (!isDetached())
alertDialog.show();
}
}
} catch (Exception e) {
if (MyApplication.inDebug)
e.printStackTrace();
}
}