[iOS] Auto Resize chrome icons - Toolbar items

Author: kubaflo

src/Controls/src/Core/Compatibility/iOS/Extensions/ToolbarItemExtensions.cs

@@ -4,6 +4,7 @@
 using CoreGraphics;
 using Foundation;
 using Microsoft.Maui.Graphics;
+using Microsoft.Maui.Graphics.Platform;
 using Microsoft.Maui.Platform;
 using ObjCRuntime;
 using UIKit;
@@ -57,6 +58,37 @@ internal static SecondarySubToolbarItem ToSecondarySubToolbarItem(this ToolbarIt
 			return new SecondarySubToolbarItem(item, action);
 		}
 
+		static UIImage ScaleImageToSystemDefaults(ImageSource imageSource, UIImage uIImage)
+		{
+			var icon = imageSource is not FontImageSource
+						? uIImage?.ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal)
+						: uIImage;
+
+			var originalImageSize = icon?.Size ?? CGSize.Empty;
+
+			// The largest height you can use for navigation bar icons in iOS.
+			// Per Apple's Human Interface Guidelines, the navigation bar height is 44 points,
+			// so using the full height ensures maximum visual clarity and maintains consistency
+			// with iOS design standards. This allows icons to utilize the entire available
+			// vertical space within the navigation bar container.
+			var defaultIconHeight = 44f;
+			var buffer = 0.1;
+			// We only check height because the navigation bar constrains vertical space (44pt height),
+			// but allows horizontal flexibility. Width can vary based on icon design and content,
+			// while height must fit within the fixed navigation bar bounds to avoid clipping.
+
+			// if the image is bigger than the default available size, resize it
+			if (icon is not null && originalImageSize.Height - defaultIconHeight > buffer)
+			{
+				if (imageSource is not FontImageSource fontImageSource || !fontImageSource.IsSet(FontImageSource.SizeProperty))
+				{
+					icon = icon.ResizeImageSource(originalImageSize.Width, defaultIconHeight, originalImageSize);
+				}
+			}
+
+			return icon;
+		}
+
 		sealed class PrimaryToolbarItem : UIBarButtonItem
 		{
 			readonly bool _forceName;
@@ -146,9 +178,7 @@ void UpdateIconAndStyle(ToolbarItem item)
 					}
 					item.IconImageSource.LoadImage(mauiContext, result =>
 					{
-						Image = item.IconImageSource is not FontImageSource
-							? result?.Value.ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal)
-							: result?.Value;
+						Image = ScaleImageToSystemDefaults(item.IconImageSource, result?.Value);
 						Style = UIBarButtonItemStyle.Plain;
 					});
 				}
@@ -304,11 +334,11 @@ void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 
 			void UpdateIcon(ToolbarItem item)
 			{
-				if (item.IconImageSource != null && !item.IconImageSource.IsEmpty)
+				if (item.IconImageSource is not null && !item.IconImageSource.IsEmpty)
 				{
 					item.IconImageSource.LoadImage(item.FindMauiContext(), result =>
 					{
-						((SecondaryToolbarItemContent)CustomView).Image = result?.Value;
+						((SecondaryToolbarItemContent)CustomView).Image = ScaleImageToSystemDefaults(item.IconImageSource, result?.Value);
 					});
 				}
 				else