Code Quality: Prevent exception when AppModel.LastSelectedTabIndex is set before MainPage is loaded (#17309)

seer-by-sentry[bot] · web-flow · commit c64b914af4d0 · 2025-07-24T22:50:18.000-04:00
Co-authored-by: seer-by-sentry[bot] &lt;157164994+seer-by-sentry[bot]@users.noreply.github.com&gt;
diff --git a/src/Files.App/Data/Models/AppModel.cs b/src/Files.App/Data/Models/AppModel.cs
@@ -43,8 +43,10 @@ public int TabStripSelectedIndex
 					if (value >= 0 && value < MainPageViewModel.AppInstances.Count)
 					{
 						var rootFrame = (Frame)MainWindow.Instance.Content;
-						var mainView = (MainPage)rootFrame.Content;
-						mainView.ViewModel.SelectedTabItem = MainPageViewModel.AppInstances[value];
+						if (rootFrame.Content is MainPage mainView)
+						{
+							mainView.ViewModel.SelectedTabItem = MainPageViewModel.AppInstances[value];
+						}
 					}
 				}
 				catch (COMException)

Original file line number	Diff line number	Diff line change
`@@ -43,8 +43,10 @@ public int TabStripSelectedIndex`
`43`	`43`	`if (value >= 0 && value < MainPageViewModel.AppInstances.Count)`
`44`	`44`	`{`
`45`	`45`	`var rootFrame = (Frame)MainWindow.Instance.Content;`
`46`		`- var mainView = (MainPage)rootFrame.Content;`
`47`		`- mainView.ViewModel.SelectedTabItem = MainPageViewModel.AppInstances[value];`
	`46`	`+ if (rootFrame.Content is MainPage mainView)`
	`47`	`+ {`
	`48`	`+ mainView.ViewModel.SelectedTabItem = MainPageViewModel.AppInstances[value];`
	`49`	`+ }`
`48`	`50`	`}`
`49`	`51`	`}`
`50`	`52`	`catch (COMException)`