How to assign callback when the user resizes a QMainWindow?

qt qwidget
Barney Szabolcs picture Barney Szabolcs · Oct 10, 2012 · Viewed 40.7k times · Source

Neither I could find a tutorial-like scheme for a resize event on QMainWindow, nor I did see any option for adding resize event in the drop-down menu at the Qt design window.

I am new to Qt. I'd like to write a slot function for a QMainWindow resize event. Is there such event? How can I do this?

Answer

RA. picture RA. · Oct 11, 2012

There is a resize event. In order to perform custom handling of the event, you'll need to create your own resize event handler. In your case, you would need to create a class that derives from QMainWindow and reimplement the resizeEvent function. Your code would look something like this:

void MyMainWindow::resizeEvent(QResizeEvent* event)
{
   QMainWindow::resizeEvent(event);
   // Your code here.
}

The Qt Scribble example also has an example of overriding the resize event (though not on the main window).

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