Qt - Make QMainWindow to non resizible in Qt Designer

Question

Is it there a way to set a QMainWindow to be non-resizible in Qt Designer? I am seeing lots of coding examples but I want to do as much UI customization in Qt Designer as I can. So far I can only get this by setting the minimum size and maximum size to be equal, but still there is the resize arrow in the corner of the window and a "maximize" button on the top of the window.

Answer 1

When you select the QMainWindow, the properties of the object does contain a field for sizePolicy, both horizontal and vertical, as mentioned by the answer of @jester and you can set those to fixed.

I have found that doesn't always work and was never sure why (perhaps to due to layouts), but as you've found out, if you set the minimumSize and maximumSize fields to the same value, it does what you want.

As for the resize arrow and maximize button, I have never been able to do that from Qt Creator (designer), so I would say it's not possible. However, just one line of code is all you should need in the constructor of your class: -

setWindowFlags(Qt::Window | Qt::CustomizeWindowHint);

By default, the window flags include Qt::WindowMaximizeButtonHint. By setting the above flags, you're stating that you want to customise the window to include the specified elements. This will also remove the minimise button, so if you want that too, you should add Qt::WindowMinimizeButtonHint