How to restore a minimized Window in code-behind?

Question

This is somewhat of a mundane question but it seems to me there is no in-built method for it in WPF. There only seems to be the WindowState property which being an enum does not help since i cannot tell whether the Window was in the Normal or Maximized state before being minimized.

When clicking the taskbar icon the window is being restored just as expected, assuming its prior state, but i cannot seem to find any defined method which does that.

So i have been wondering if i am just missing something or if i need to use some custom interaction logic.

(I'll post my current solution as answer)

are you calling this.Show() ? or you are changing the state? — Akash Kava, Apr 03 '11 at 18:53
@Akash Kava `Window.Show` only affects the visibility, it has no effect on the window's state. Minimization is a state-issue. — H.B., Apr 03 '11 at 19:36
Well I checked reflector calling Show() does call ShowWindow api as mentioned by others, I wanted to know whether have you tried this.Show() ? because I have used it and may be I have not noticed. — Akash Kava, Apr 04 '11 at 07:53
It does not call `ShowWindow` and it does not work. As i said, it only sets the visibility (and waits for the loaded event to fire). — H.B., Apr 04 '11 at 11:13

score 95 · Accepted Answer · edited Dec 24 '22 at 05:55

95

Not sure this will work for everybody, but I ran into this today and someone on the team suggested "have you tried Normal"?

Turns out he was right. The following seems to nicely restore your window:

if (myWindow.WindowState == WindowState.Minimized)
    myWindow.WindowState = WindowState.Normal;

That works just fine, restoring the window to Maximized if needed. It seems critical to check for the minimized state first as calling WindowState.Normal a second time will "restore" your window to its non-maximized state.

edited Dec 24 '22 at 05:55

starball

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answered Jul 26 '11 at 22:33

Eric Liprandi

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Similar sentiments to H.B. Spent ten minutes wondering how to pull this off before stumbling here and seeing it was just automatic. – aggieNick02 Apr 12 '13 at 20:33

score 26 · Answer 2 · answered Jul 25 '15 at 11:17

26

SystemCommands class has a static method called RestoreWindow that restores the window to previous state.

SystemCommands.RestoreWindow(this); // this being the current window

[Note : SystemCommands class is part of .NET 4.5+ (MSDN Ref) for projects that target to earlier versions of Framework can use the WPF Shell extension (MSDN Ref)]

answered Jul 25 '15 at 11:17

kiran

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+1 When use `ShowInTaskbar="False"` with `TrayIcon` and changing `Visibility to Hidden`, then is problem with restore window back to Normal. But this works great. – slavoo Apr 06 '16 at 07:08

score 16 · Answer 3 · answered Apr 04 '11 at 06:42

16

WPF's point of view is that this is an OS feature. If you want to mess around with OS features you might have to get your hands dirty. Luckily they have provided us with the tools to do so. Here is a UN-minimize method that takes a WPF window and uses WIN32 to accomplish the effect without recording any state:

public static class Win32
{
    public static void Unminimize(Window window)
    {
        var hwnd = (HwndSource.FromVisual(window) as HwndSource).Handle;
        ShowWindow(hwnd, ShowWindowCommands.Restore);
    }

    [DllImport("user32.dll")]
    private static extern bool ShowWindow(IntPtr hWnd, ShowWindowCommands nCmdShow);

    private enum ShowWindowCommands : int
    {
        /// <summary>
        /// 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.
        /// </summary>
        Restore = 9,
    }
}

answered Apr 04 '11 at 06:42

Rick Sladkey

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Thank you for your answer. I almost never useed external calls so far so i am wondering though, is there a way to import the full `ShowWindowCommands` enum? – H.B. Apr 04 '11 at 11:31
@H.B. The site pinvoke.net has the full enum; I scraped just the one line we needed. You can google "pinvoke _win32api_" e.g. "pinvoke ShowWindow" to find code to cut and paste. The rest of ShowWindowCommands is at http://pinvoke.net/default.aspx/Enums/ShowWindowCommand.html – Rick Sladkey Apr 04 '11 at 16:18
Thank you again (i was not aware that a partial definition of the enum would be sufficient) – H.B. Apr 04 '11 at 16:40
1

Because it is interop only the size matters; even an int or uint would be OK. – Rick Sladkey Apr 04 '11 at 17:53
A new answer came in, sorry to take the accept from you but simplicity is obviously preferable. – H.B. Jul 26 '11 at 23:04

Dark Knight · Answer 4 · 2015-12-11T21:49:44.507

7

For some reason,

WindowState = WindowState.Normal;

didn't work for me. So I used following code & it worked..

 Show();
 WindowState = WindowState.Normal;

edited Dec 11 '15 at 21:49

answered Dec 11 '15 at 21:43

Dark Knight

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Worked for me :) – Naveen Kumar V Sep 19 '18 at 11:33

score 3 · Answer 5 · answered Apr 03 '11 at 18:24

Here is how i get it to restore right now: I handle the StateChanged event to keep track of the last state that was not Minimized

WindowState _lastNonMinimizedState = WindowState.Maximized;
private void Window_StateChanged(object sender, EventArgs e)
{
    if (this.WindowState != System.Windows.WindowState.Minimized)
    {
        _lastNonMinimizedState = WindowState;
    }
}

To restore i then have to set that WindowState respectively:

this.WindowState = _lastNonMinimizedState;

score 2 · Answer 6 · answered Apr 16 '13 at 11:18

Hmmm, the accepted answer did not work for me. The "maximized" window, when recalled from the task bar would end up centering itself (displaying in its Normal size, even though its state is Maximized) on the screen and things like dragging the window by its title bar ended up not working. Eventually (pretty much by trial-and-error), I figured out how to do it. Thanks to @H.B. and @Eric Liprandi for guiding me to the answer! Code follows:

private bool windowIsMinimized = false;
private WindowState lastNonMinimizedState = WindowState.Normal;

private void Window_StateChanged(object sender, EventArgs e)
{
    if (this.windowIsMinimized)
    {
        this.windowIsMinimized = false;
        this.WindowState = WindowState.Normal;
        this.WindowState = this.lastNonMinimizedState;
    }
    else if (this.WindowState == WindowState.Minimized)
    {
        this.windowIsMinimized = true;
    }
}

private void Window_MinimizeButtonClicked(object sender, MouseButtonEventArgs e)
{
    this.lastNonMinimizedState = this.WindowState;
    this.WindowState = WindowState.Minimized;
    this.windowIsMinimized = true;
}

private void Window_MaximizeRestoreButtonClicked(object sender, MouseButtonEventArgs e)
{
    if (this.WindowState == WindowState.Normal)
    {
        this.WindowState = WindowState.Maximized;
    }
    else
    {
        this.WindowState = WindowState.Normal;
    }

    this.lastNonMinimizedState = this.WindowState;
}

score 0 · Answer 7 · answered Apr 03 '11 at 18:32

In native Windows you can restore your window to a previous state with ShowWindow(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.

There's surely .Net counterpart to that.

How to restore a minimized Window in code-behind?

7 Answers7

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