Fixed: Selection isn't cleared when switching between panes (#11745)

Author: ferrariofilippo

src/Files.App/Views/PaneHolderPage.xaml

@@ -53,7 +53,7 @@
 			x:Name="PaneLeft"
 			ContentChanged="Pane_ContentChanged"
 			IsPageMainPane="True"
-			Loaded="PaneLeft_Loaded"
+			Loaded="Pane_Loaded"
 			NavParams="{x:Bind NavParamsLeft, Mode=OneWay}"
 			PaneHolder="{x:Bind}" />
 
@@ -65,7 +65,7 @@
 				x:Name="PaneRight"
 				ContentChanged="Pane_ContentChanged"
 				IsPageMainPane="False"
-				Loaded="PaneRight_Loaded"
+				Loaded="Pane_Loaded"
 				NavParams="{x:Bind NavParamsRight, Mode=OneWay}"
 				PaneHolder="{x:Bind}" />
 		</Border>

src/Files.App/Views/PaneHolderPage.xaml.cs

@@ -330,19 +330,20 @@ public void CloseActivePane()
 			IsRightPaneVisible = false;
 		}
 
-		private void PaneLeft_Loaded(object sender, RoutedEventArgs e)
+		private void Pane_Loaded(object sender, RoutedEventArgs e)
 		{
-			(sender as UIElement).GotFocus += Pane_GotFocus;
-		}
-
-		private void PaneRight_Loaded(object sender, RoutedEventArgs e)
-		{
-			(sender as UIElement).GotFocus += Pane_GotFocus;
+			((UIElement)sender).GotFocus += Pane_GotFocus;
 		}
 
 		private void Pane_GotFocus(object sender, RoutedEventArgs e)
 		{
-			ActivePane = sender == PaneLeft ? PaneLeft : PaneRight;
+			var isLeftPane = sender == PaneLeft;
+			if (isLeftPane && (PaneRight?.SlimContentPage?.IsItemSelected ?? false))
+				PaneRight.SlimContentPage.ItemManipulationModel.ClearSelection();
+			else if (!isLeftPane && (PaneLeft?.SlimContentPage?.IsItemSelected ?? false))
+				PaneLeft.SlimContentPage.ItemManipulationModel.ClearSelection();
+
+			ActivePane = isLeftPane ? PaneLeft : PaneRight;
 		}
 
 		public void Dispose()