How to assign callback when the user resizes a QMainWindow?

Question

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 1

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).

Answer 2

This works in Qt5 with me f.e. to resize the icon in a QTableWidget:

mainWindow.h ... private: void resizeEvent(QResizeEvent*); ...  mainWindow.cpp ... void mainWindow::resizeEvent(QResizeEvent*) {     tableWidget->setIconSize(QSize(tableWidget->size()/7)); //7 or whatever number you need it to get the full icon size }