Fix issue where content of floating window is set to inactive

source/Components/AvalonDock/Controls/LayoutAnchorableFloatingWindowControl.cs

@@ -226,14 +226,17 @@
 			switch (msg)
 			{
 				case Win32Helper.WM_ACTIVATE:
-					var isInactive = ((int)wParam & 0xFFFF) == Win32Helper.WA_INACTIVE;
-					if (_model.IsSinglePane)
-					{
-						LayoutFloatingWindowControlHelper.ActiveTheContentOfSinglePane(this, !isInactive);
-					}
-					else
-					{
-						LayoutFloatingWindowControlHelper.ActiveTheContentOfMultiPane(this, !isInactive);
+					var isActive = ((int)wParam & 0xFFFF) != Win32Helper.WA_INACTIVE;
+					if (isActive)
+					{ 
+						if (_model.IsSinglePane)
+						{
+							LayoutFloatingWindowControlHelper.ActiveTheContentOfSinglePane(this);
+						}
+						else
+						{
+							LayoutFloatingWindowControlHelper.ActiveTheContentOfMultiPane(this);
+						}
 					}
 
 					handled = true;

source/Components/AvalonDock/Controls/LayoutDocumentFloatingWindowControl.cs

@@ -107,14 +107,17 @@
 			switch (msg)
 			{
 				case Win32Helper.WM_ACTIVATE:
-					var isInactive = ((int)wParam & 0xFFFF) == Win32Helper.WA_INACTIVE;
-					if (_model.IsSinglePane)
+					var isActive = ((int)wParam & 0xFFFF) != Win32Helper.WA_INACTIVE;
+					if (isActive)
 					{
-						LayoutFloatingWindowControlHelper.ActiveTheContentOfSinglePane(this, !isInactive);
-					}
-					else
-					{
-						LayoutFloatingWindowControlHelper.ActiveTheContentOfMultiPane(this, !isInactive);
+						if (_model.IsSinglePane)
+						{
+							LayoutFloatingWindowControlHelper.ActiveTheContentOfSinglePane(this, true);
+						}
+						else
+						{
+							LayoutFloatingWindowControlHelper.ActiveTheContentOfMultiPane(this, true);
+						}
 					}
 
 					handled = true;
@@ -419,4 +422,4 @@
 			}
 		}
 	}
-}
+}

source/TestApp/MainWindow.xaml

@@ -115,6 +115,13 @@
                                     Foreground="White"
                                     Text="{Binding TestTimer, Mode=OneWay, StringFormat='Document 2 Attached to Timer ->\{0\}'}" />
                             </LayoutDocument>
+							<LayoutDocument Title="Document 3" ContentId="document3">
+								<Button
+									Margin="25"
+									VerticalAlignment="Top"
+									Click="ShowMessageBox_click"
+									Content="Click to open message box" />
+							</LayoutDocument>
                         </LayoutDocumentPane>
                     </LayoutDocumentPaneGroup>
                     <LayoutAnchorablePaneGroup DockWidth="50">

source/TestApp/MainWindow.xaml.cs

@@ -256,5 +256,7 @@ private void OnNewFloatingWindow(object sender, RoutedEventArgs e)
             anchorable.AddToLayout(dockManager,AnchorableShowStrategy.Most);
             anchorable.Float();
         }
+
+		private void ShowMessageBox_click(object sender, RoutedEventArgs e) => MessageBox.Show("Test messge", "Test");
     }
 }