android dialog弹出的情况下监听返回键

view = LayoutInflater.from(getActivity()).inflate(
R.layout.dialog_tips, null);
　　title2 = (TextView) view.findViewById(R.id.title2);

　　dialog = new Dialog(getActivity());
dialog.setOnKeyListener(new OnKeyListener() {

@Override
public boolean onKey(DialogInterface dialog,
int keyCode, KeyEvent event) {
　　if (keyCode == KeyEvent.KEYCODE_BACK
　　　　&& event.getRepeatCount() == 0) {
　　　　getActivity().finish();
　　}
　　　　return false;
　　}
　　});
　　dialog.getWindow().setBackgroundDrawable(
　　new ColorDrawable(
　　android.R.color.transparent));
　　dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(view);
dialog.getWindow()
.setLayout(
ScreenUtil
.getScreenWidth(getActivity()) - 50,
DensityUtil.dp2px(400));
dialog.show();