Fix: Fixed crash on the tags settings page (#11447)

Author: ferrariofilippo

src/Files.App/Helpers/ColorHelpers.cs

@@ -1,34 +1,53 @@
 using CommunityToolkit.WinUI.Helpers;
 using System;
+using System.Globalization;
 using Windows.UI;
 
 namespace Files.App.Helpers
 {
 	internal static class ColorHelpers
 	{
+		private const int COLOR_LENGTH = 7;
+		private const int COLOR_LENGTH_INCLUDING_ALPHA = 9;
+
+		private static readonly Color unknownTagColor = Color.FromArgb(255, 0x9E, 0xA3, 0xA1);
+
 		/// <summary>
 		/// Converts Hex to Windows.UI.Color.
 		/// </summary>
-		public static Color FromHex(string colorHex)
+		public static Color FromHex(string? colorHex)
 		{
+			// If Hex string is invalid, return Unknown Tag's color
+			if (
+				string.IsNullOrWhiteSpace(colorHex) ||
+				(colorHex.Length != COLOR_LENGTH && colorHex.Length != COLOR_LENGTH_INCLUDING_ALPHA)
+				)
+				return unknownTagColor;
+
 			colorHex = colorHex.Replace("#", string.Empty);
 
 			var alphaOffset = colorHex.Length == 8 ? 2 : 0;
 
-			var a = alphaOffset == 2 ? (byte)Convert.ToUInt32(colorHex.Substring(0, 2), 16) : (byte)255;
-			var r = (byte)Convert.ToUInt32(colorHex.Substring(alphaOffset, 2), 16);
-			var g = (byte)Convert.ToUInt32(colorHex.Substring(alphaOffset + 2, 2), 16);
-			var b = (byte)Convert.ToUInt32(colorHex.Substring(alphaOffset + 4, 2), 16);
+			var a = (byte)255;
+			var alphaValid = alphaOffset == 0 || byte.TryParse(colorHex.AsSpan(0, 2), NumberStyles.HexNumber, null, out a);
+
+			if (
+				alphaValid &&
+				byte.TryParse(colorHex.AsSpan(alphaOffset, 2), NumberStyles.HexNumber, null, out byte r) &&
+				byte.TryParse(colorHex.AsSpan(alphaOffset + 2, 2), NumberStyles.HexNumber, null, out byte g) &&
+				byte.TryParse(colorHex.AsSpan(alphaOffset + 4, 2), NumberStyles.HexNumber, null, out byte b)
+				)
+				return Color.FromArgb(a, r, g, b);
 
-			return Color.FromArgb(a, r, g, b);
+			return unknownTagColor;
 		}
 
 		/// <summary>
 		/// Converts Uint to Windows.UI.Color.
 		/// </summary>
 		public static Color FromUint(this uint value)
 		{
-			return Windows.UI.Color.FromArgb((byte)((value >> 24) & 0xFF),
+			return Color.FromArgb((byte)((value >> 24) & 0xFF),
 					   (byte)((value >> 16) & 0xFF),
 					   (byte)((value >> 8) & 0xFF),
 					   (byte)(value & 0xFF));

src/Files.App/ServicesImplementation/Settings/FileTagsSettingsService.cs

@@ -1,5 +1,6 @@
 using Files.App.Extensions;
 using Files.App.Filesystem;
+using Files.App.Helpers;
 using Files.App.Serialization;
 using Files.App.Serialization.Implementation;
 using Files.Backend.Services.Settings;
@@ -38,7 +39,15 @@ public FileTagsSettingsService()
 
 		public IList<TagViewModel> FileTagList
 		{
-			get => Get<List<TagViewModel>>(DefaultFileTags);
+			get
+			{
+				var tags = Get<List<TagViewModel>>(DefaultFileTags);
+
+				foreach (var tag in tags!)
+					tag.Color = ColorHelpers.FromHex(tag.Color).ToString();
+
+				return tags;
+			}
 			set
 			{
 				Set(value);
@@ -168,14 +177,14 @@ public override object ExportSettings()
 
 		private void UntagAllFiles(string uid)
 		{
-			var tagDoDelete = new string [] { uid };
+			var tagDoDelete = new string[] { uid };
 
 			foreach (var item in FileTagsHelper.GetDbInstance().GetAll())
 			{
 				if (item.Tags.Contains(uid))
-				{ 
+				{
 					FileTagsHelper.WriteFileTag(
-						item.FilePath, 
+						item.FilePath,
 						item.Tags.Except(tagDoDelete).ToArray());
 				}
 			}