Code Quality: Ensure minimum size for UI elements based on DPI scaling (#17462)

Co-authored-by: seer-by-sentry[bot] <157164994+seer-by-sentry[bot]@users.noreply.github.com>

Author: seer-by-sentry[bot]

src/Files.App/Data/Items/WidgetFolderCardItem.cs

@@ -43,7 +43,10 @@ public async Task LoadCardThumbnailAsync()
 			if (string.IsNullOrEmpty(Path))
 				return;
 
-			Item.TryGetThumbnail((int)(Constants.ShellIconSizes.Large * App.AppModel.AppWindowDPI), SIIGBF.SIIGBF_ICONONLY, out var rawThumbnailData);
+			var thumbnailSize = (int)(Constants.ShellIconSizes.Large * App.AppModel.AppWindowDPI);
+			// Ensure thumbnail size is at least 1 to prevent layout errors
+			thumbnailSize = Math.Max(1, thumbnailSize);
+			Item.TryGetThumbnail(thumbnailSize, SIIGBF.SIIGBF_ICONONLY, out var rawThumbnailData);
 			if (rawThumbnailData is null)
 				return;
 

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

@@ -129,10 +129,18 @@ public string PCloudDrivePath
 		/// <summary>
 		/// Gets or sets a value indicating the AppWindow DPI.
 		/// </summary>
-		private float _AppWindowDPI = PInvoke.GetDpiForWindow((HWND)MainWindow.Instance.WindowHandle) / 96f;
+		private float? _AppWindowDPI = null;
 		public float AppWindowDPI
 		{
-			get => _AppWindowDPI;
+			get
+			{
+				if (_AppWindowDPI is null || _AppWindowDPI == 0f)
+				{
+					var dpi = PInvoke.GetDpiForWindow((HWND)MainWindow.Instance.WindowHandle);
+					_AppWindowDPI = dpi > 0 ? dpi / 96f : 1.0f; // Fallback to 1.0f if invalid DPI
+				}
+				return _AppWindowDPI.Value;
+			}
 			set => SetProperty(ref _AppWindowDPI, value);
 		}
 	}

src/Files.App/Utils/Storage/Helpers/FilePropertiesHelpers.cs

@@ -100,8 +100,8 @@ public static void OpenPropertiesWindow(object item, IShellPage associatedInstan
 				propertiesWindow.Closed += PropertiesWindow_Closed;
 			}
 
-			var width = Convert.ToInt32(800 * App.AppModel.AppWindowDPI);
-			var height = Convert.ToInt32(500 * App.AppModel.AppWindowDPI);
+			var width = Math.Max(1, Convert.ToInt32(800 * App.AppModel.AppWindowDPI));
+			var height = Math.Max(1, Convert.ToInt32(500 * App.AppModel.AppWindowDPI));
 
 			propertiesWindow.AppWindow.Resize(new(width, height));
 			propertiesWindow.IsMinimizable = false;

src/Files.App/Utils/Storage/Helpers/FileThumbnailHelper.cs

@@ -13,6 +13,8 @@ public static class FileThumbnailHelper
 		public static async Task<byte[]?> GetIconAsync(string path, uint requestedSize, bool isFolder, IconOptions iconOptions)
 		{
 			var size = iconOptions.HasFlag(IconOptions.UseCurrentScale) ? requestedSize * App.AppModel.AppWindowDPI : requestedSize;
+			// Ensure size is at least 1 to prevent layout errors
+			size = Math.Max(1, size);
 
 			return await Win32Helper.StartSTATask(() => Win32Helper.GetIcon(path, (int)size, isFolder, iconOptions));
 		}