How to un-minimise a window to the exact previous state (restored or maximised)?

Question

In Windows, I have a minimised window that is the foreground window (GetForegroundWindow). I now want to un-minimise the window so that it becomes visible again. How can I bring the window back to its previous state? I.e., if the window was "restored" before minimised, it should be restored, if it was maximised before being minimised, it should be maximised again and especially not restored or something.

It seems I can only determine the window's current state out of {minimised, restored, maximised}, but theoretically, minimised and maximised should be flags that can be set together.

How does the Explorer taskbar know in what state to show a window if the user clicks on it?

Answer 1

If you use something like C, you can look on to ShowWindow function:

ShowWindow(hWnd, SW_RESTORE)

SW_RESTORE
Activates and displays the window. If the window is minimized or maximized, the system restores it to its original size and position. An application should specify this flag when restoring a minimized window.

Answer 2

Without getting technical (I don't know the language you are using for example), the program needs to store the current normal size, the current state and the previous state.

Then when restoring from minimized it can check the previous state and size.

In WPF the current size and state are stored in the Top, Left, Height, Width and WindowState properties of the main window. A copy of the location and size are held in the RestoreBounds structure and this is used by the base classes (so you don't have to) when restoring the window from Maximised for example.