Android - change custom title view at run time

I am using a custom title view in my application for each activity. In one of the activities, based on button clicks I need to change the custom title view. Now this works fine every time when I make a call to setFeatureInt.

But if I try to update any items in the custom title (say change the text of a button or a text view on the title), the update does not take place.

Debugging through the code shows that the text view and button instances are not null and I can also see the custom title bar. But the text on the text view or the button is not updated. Has anyone else faced this problem? How do I resolve it?

Thanks.

EDIT

Here's what I tried. Does not get updated even on calling postInvalidate.

    getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.text_title);

    TextView databar = (TextView) findViewById(R.id.title_text);
    databar.setText("Some Text");
    databar.postInvalidate();

    Button leftButton = (Button) findViewById(R.id.left_btn);
    leftButton.setOnClickListener(mLeftListener);
    leftButton.setText("Left Btn");
    leftButton.postInvalidate();

    Button rightBtn = (Button) findViewById(R.id.right_btn);
    rightBtn.setOnClickListener(mRightListener);
    rightBtn.postInvalidate();