Fix: Fixed warnings in settings (#13968)

Author: yaira2

src/Files.App/Data/Models/FolderSettingsViewModel.cs

@@ -326,15 +326,17 @@ public static void SetLayoutPreferencesForPath(string folderPath, LayoutPreferen
 			if (!userSettingsService.FoldersSettingsService.SyncFolderPreferencesAcrossDirectories)
 			{
 				var folderFRN = NativeFileOperationsHelper.GetFolderFRN(folderPath);
-				WriteLayoutPreferencesToDb(folderPath.TrimPath(), folderFRN, prefs);
+				var trimmedFolderPath = folderPath.TrimPath();
+				if (trimmedFolderPath is not null)
+					WriteLayoutPreferencesToDb(trimmedFolderPath, folderFRN, prefs);
 			}
 			else
 			{
 				userSettingsService.FoldersSettingsService.DefaultLayoutMode = prefs.LayoutMode;
 				userSettingsService.LayoutSettingsService.DefaultGridViewSize = prefs.GridViewSize;
 
 				// Do not save options which only work in recycle bin or cloud folders or search results as global
-				if (prefs.DirectorySortOption != SortOption.Path && 
+				if (prefs.DirectorySortOption != SortOption.Path &&
 					prefs.DirectorySortOption != SortOption.OriginalFolder &&
 					prefs.DirectorySortOption != SortOption.DateDeleted &&
 					prefs.DirectorySortOption != SortOption.SyncStatus)
@@ -460,7 +462,8 @@ private static LayoutPreferences GetDefaultLayoutPreferences(string folderPath)
 
 			if (folderPath == Constants.UserEnvironmentPaths.DownloadsPath)
 				// Default for downloads folder is to group by date created
-				return new LayoutPreferences() {
+				return new LayoutPreferences()
+				{
 					DirectoryGroupOption = GroupOption.DateCreated,
 					DirectoryGroupDirection = SortDirection.Descending,
 					DirectoryGroupByDateUnit = GroupByDateUnit.Year

src/Files.App/ViewModels/Settings/AboutViewModel.cs

@@ -25,7 +25,7 @@ public class AboutViewModel : ObservableObject
 		public ICommand OpenPrivacyPolicyCommand { get; }
 		public ICommand OpenCrowdinCommand { get; }
 
-		private string _ThirdPartyNotices;
+		private string _ThirdPartyNotices = string.Empty;
 		public string ThirdPartyNotices
 		{
 			get => _ThirdPartyNotices;

src/Files.App/ViewModels/Settings/AdvancedViewModel.cs

@@ -1,7 +1,6 @@
 // Copyright (c) 2023 Files Community
 // Licensed under the MIT License. See the LICENSE.
 
-using Files.App.Utils.Shell;
 using Microsoft.Extensions.Logging;
 using Microsoft.Win32;
 using SevenZip;
@@ -18,7 +17,7 @@ namespace Files.App.ViewModels.Settings
 	public class AdvancedViewModel : ObservableObject
 	{
 		private IUserSettingsService UserSettingsService { get; } = Ioc.Default.GetRequiredService<IUserSettingsService>();
-		
+
 		private readonly IFileTagsSettingsService fileTagsSettingsService = Ioc.Default.GetRequiredService<IFileTagsSettingsService>();
 
 		public ICommand SetAsDefaultExplorerCommand { get; }
@@ -93,7 +92,8 @@ private async Task SetAsDefaultExplorerAsync()
 			try
 			{
 				using var regProcess = Process.Start(new ProcessStartInfo("regedit.exe", @$"/s ""{Path.Combine(destFolder, IsSetAsDefaultFileManager ? "SetFilesAsDefault.reg" : "UnsetFilesAsDefault.reg")}""") { UseShellExecute = true, Verb = "runas" });
-				await regProcess.WaitForExitAsync();
+				if (regProcess is not null)
+					await regProcess.WaitForExitAsync();
 			}
 			catch
 			{