Restore layout for window doesn't work if it's currently maximized

[bbc131]

The problem can be reproduced with the example qtwidgets_dockwidgets:

1. Turn your mainwindow in 'normal' state, i.e. not 'maximized' etc.
2. Save the current layout
3. Maximize your mainwindow
4. Restore the saved layout

Now, on Windows, the mainwindow looks like correctly restored but isn't.
For example, you cannot change its size by click'n'drag on its edges, you first need to move it a bit by click'n'drag at the windows title bar.
(On Ubuntu, the restoring also doesn't work, but behaves differently. The window just stays maximized.)

To fix this, I think there are two things in LayoutSaver::restoreLayout(..), that need to be changed.

1. the window-state has to be set, if the desired state differs from the current state, not only if the desired state is not 'normal'/WindowState::None.
2. deserializeWindowGeometry cannot set the geometry correctly, if the window is currently maximized, so the window-state should be changed beforehand.

I checked this by playing a bit and this hack seems to solve the problem:

         if (!(d->m_restoreOptions & InternalRestoreOption::SkipMainWindowGeometry)) {
             Window::Ptr window = mainWindow->view()->window();
+            if (window->windowState() != WindowState::None) {
+                if (auto w = mainWindow->view()->window()) {
+                    w->setWindowState(WindowState::None);
+                }
+            }
             d->deserializeWindowGeometry(mw, window);
-            if (mw.windowState != WindowState::None) {
+            if (mw.windowState != window->windowState()) {
                 if (auto w = mainWindow->view()->window()) {
                     w->setWindowState(mw.windowState);
                 }

[iamsergio]

You might be right, but I would like to reproduce this as well, to maybe write a test.

Can't repro on Win11 / Qt 6.6.2, stock qtwidgets_dockwidgets without flags.

Which versions are you on ?

[bbc131]

Sure, my code above should just be a hint where / what the problems are...
I use Win 10 and Qt 5.15.8
Can reproduce it with the default example qtwidgets_dockwidgets without any flags.

[iamsergio]

Thanks, reproduced with Qt 5

[iamsergio]

Works for me now, thanks for the investigation

[bbc131]

I think there is a regression.
The case, where you first maximize the window, save this (maximized) layout and try to restore this later, doesn't work anymore.
This worked before.

[iamsergio]

I've added tests for that case as well now, and fixed it.

Windows and KDE pass the test.
Ubuntu and macOS pass a manual test, but not the automatic one, need to investigate further.

[iamsergio]

Tests are passing on mac and ubuntu now