Enable/ Disable QMouse Events based on QRect

[Sidii]

Dear All,
I have one specific requirement. As per that there is one parent window. New child windows will be created on the fly of different sizes., if a window is a popup then it will be displayed on top. The problem is that the popup window size is smaller, so i am able to click the buttons which are placed visible in the back side of the underlying windows.

I tried setting the modality of the window but it is not working because there is only one parent window and all others are child windows. And i want to block the button press of the sibling window.

Is it possible to lock the screen using QRect and make it invisible for the mouse click events so that only a particular section of the window remains active. Example: i want to disable all the mouse events outside a particular QRect, and enable all the mouse clicks that are inside that QRect.

Kindly let me know how it can be achieved.

Thanks