From ffe74ceaa49b7be878c006c030422bf2d5b0fa73 Mon Sep 17 00:00:00 2001
From: Max Katz <maxkatz6@outlook.com>
Date: Thu, 17 Nov 2022 19:54:14 -0500
Subject: [PATCH] Merge pull request #9221 from
 AvaloniaUI/fixes/8869-show-windowstate

Fix setting WindowState before showing Window.
---
 samples/IntegrationTestApp/MainWindow.axaml         |  6 ++++++
 samples/IntegrationTestApp/MainWindow.axaml.cs      |  2 ++
 samples/IntegrationTestApp/ShowWindowTest.axaml     |  2 +-
 src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs | 10 +++++++---
 src/Windows/Avalonia.Win32/WindowImpl.cs            | 11 +++++++++--
 5 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/samples/IntegrationTestApp/MainWindow.axaml b/samples/IntegrationTestApp/MainWindow.axaml
index f4d6ad3ace9..952165b827e 100644
--- a/samples/IntegrationTestApp/MainWindow.axaml
+++ b/samples/IntegrationTestApp/MainWindow.axaml
@@ -109,6 +109,12 @@
             <ComboBoxItem>CenterScreen</ComboBoxItem>
             <ComboBoxItem>CenterOwner</ComboBoxItem>
           </ComboBox>
+          <ComboBox Name="ShowWindowState" SelectedIndex="0">
+            <ComboBoxItem>Normal</ComboBoxItem>
+            <ComboBoxItem>Minimized</ComboBoxItem>
+            <ComboBoxItem>Maximized</ComboBoxItem>
+            <ComboBoxItem>FullScreen</ComboBoxItem>
+          </ComboBox>
           <Button Name="ShowWindow">Show Window</Button>
           <Button Name="SendToBack">Send to Back</Button>
           <Button Name="ExitFullscreen">Exit Fullscreen</Button>
diff --git a/samples/IntegrationTestApp/MainWindow.axaml.cs b/samples/IntegrationTestApp/MainWindow.axaml.cs
index 1dab74dc9e7..d086ffb97b4 100644
--- a/samples/IntegrationTestApp/MainWindow.axaml.cs
+++ b/samples/IntegrationTestApp/MainWindow.axaml.cs
@@ -53,6 +53,7 @@ private void ShowWindow()
             var sizeTextBox = this.GetControl<TextBox>("ShowWindowSize");
             var modeComboBox = this.GetControl<ComboBox>("ShowWindowMode");
             var locationComboBox = this.GetControl<ComboBox>("ShowWindowLocation");
+            var stateComboBox = this.GetControl<ComboBox>("ShowWindowState");
             var size = !string.IsNullOrWhiteSpace(sizeTextBox.Text) ? Size.Parse(sizeTextBox.Text) : (Size?)null;
             var owner = (Window)this.GetVisualRoot()!;
 
@@ -68,6 +69,7 @@ private void ShowWindow()
             }
 
             sizeTextBox.Text = string.Empty;
+            window.WindowState = (WindowState)stateComboBox.SelectedIndex;
 
             switch (modeComboBox.SelectedIndex)
             {
diff --git a/samples/IntegrationTestApp/ShowWindowTest.axaml b/samples/IntegrationTestApp/ShowWindowTest.axaml
index 4001bac7e20..effa55e0611 100644
--- a/samples/IntegrationTestApp/ShowWindowTest.axaml
+++ b/samples/IntegrationTestApp/ShowWindowTest.axaml
@@ -29,7 +29,7 @@
       <ComboBoxItem>Normal</ComboBoxItem>
       <ComboBoxItem>Minimized</ComboBoxItem>
       <ComboBoxItem>Maximized</ComboBoxItem>
-      <ComboBoxItem>Fullscreen</ComboBoxItem>
+      <ComboBoxItem>FullScreen</ComboBoxItem>
     </ComboBox>
     <Button Name="HideButton" Grid.Row="8" Command="{Binding $parent[Window].Hide}">Hide</Button>
   </Grid>
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs b/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
index 88a0744e3ee..e5c01f99f64 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.AppWndProc.cs
@@ -399,9 +399,13 @@ protected virtual unsafe IntPtr AppWndProc(IntPtr hWnd, uint msg, IntPtr wParam,
                             Resized(clientSize / RenderScaling, _resizeReason);
                         }
 
-                        var windowState = size == SizeCommand.Maximized ?
-                            WindowState.Maximized :
-                            (size == SizeCommand.Minimized ? WindowState.Minimized : WindowState.Normal);
+                        var windowState = size switch
+                        {
+                            SizeCommand.Maximized => WindowState.Maximized,
+                            SizeCommand.Minimized => WindowState.Minimized,
+                            _ when _isFullScreenActive => WindowState.FullScreen,
+                            _ => WindowState.Normal,
+                        };
 
                         if (windowState != _lastWindowState)
                         {
diff --git a/src/Windows/Avalonia.Win32/WindowImpl.cs b/src/Windows/Avalonia.Win32/WindowImpl.cs
index f62335b3f3d..922bffd2fdb 100644
--- a/src/Windows/Avalonia.Win32/WindowImpl.cs
+++ b/src/Windows/Avalonia.Win32/WindowImpl.cs
@@ -245,6 +245,11 @@ public WindowState WindowState
         {
             get
             {
+                if (!IsWindowVisible(_hwnd))
+                {
+                    return _showWindowState;
+                }
+
                 if (_isFullScreenActive)
                 {
                     return WindowState.FullScreen;
@@ -511,6 +516,9 @@ public IRenderer CreateRenderer(IRenderRoot root)
 
         public void Resize(Size value, PlatformResizeReason reason)
         {
+            if (WindowState != WindowState.Normal)
+                return;
+
             int requestedClientWidth = (int)(value.Width * RenderScaling);
             int requestedClientHeight = (int)(value.Height * RenderScaling);
 
@@ -856,11 +864,10 @@ private void SetFullScreen(bool fullscreen)
 
                 var window_rect = monitor_info.rcMonitor.ToPixelRect();
 
+                _isFullScreenActive = true;
                 SetWindowPos(_hwnd, IntPtr.Zero, window_rect.X, window_rect.Y,
                              window_rect.Width, window_rect.Height,
                              SetWindowPosFlags.SWP_NOZORDER | SetWindowPosFlags.SWP_NOACTIVATE | SetWindowPosFlags.SWP_FRAMECHANGED);
-
-                _isFullScreenActive = true;
             }
             else
             {