Android AlertDialog 獲取PositiveButton的控制權

final AlertDialog.Builder alert = new AlertDialog.Builder(
CloudSyncActivity.this);
alert.setIcon(getResources().getDrawable(R.drawable.about));
alert.setTitle("標題");
alert.setMessage("輸入提示信息");
alert.setPositiveButton("確認",
new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog,
int which) {

//控制點擊按鈕不消失問題
try
{
Field field = dialog.getClass()
.getSuperclass().getDeclaredField(
"mShowing" );
field.setAccessible( true );
// 將mShowing變量設為false，表示對話框已關閉
field.set(dialog, false );
dialog.dismiss();

}
catch (Exception e)
{

}
//獲取按鈕對象
Button PositiveButton=((AlertDialog)dialog).getButton(AlertDialog.BUTTON_POSITIVE);
//對按鈕進行操作
PositiveButton.setVisibility(View.GONE);

}
});
alert.setNegativeButton("取消",
new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog,
int which) {
try
{
Field field = dialog.getClass()
.getSuperclass().getDeclaredField(
"mShowing" );
field.setAccessible( true );
// 將mShowing變量設為false，表示對話框已關閉
field.set(dialog, true );
dialog.dismiss();

}
catch (Exception e)
{

}
}
});
alert.show();