[iOS] Fixed crash updating ToolbarItem icon (already disposed)

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue6387.xaml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<controls:TestContentPage
+    xmlns:controls="clr-namespace:Xamarin.Forms.Controls"
+    xmlns="http://xamarin.com/schemas/2014/forms"
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+    x:Class="Xamarin.Forms.Controls.Issues.Issue6387"
+    Title="Issue 6387">
+    <ContentPage.Content>
+        <StackLayout>
+            <Label
+                Padding="12"
+                Text="Tap the ToolBarItem with an Icon. Without exceptions, the test has passed." />
+        </StackLayout>
+    </ContentPage.Content>
+</controls:TestContentPage>

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue6387.xaml.cs

@@ -0,0 +1,61 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+using System.Reflection;
+
+#if UITEST
+using Xamarin.UITest;
+using NUnit.Framework;
+using Xamarin.Forms.Core.UITests;
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+#if UITEST
+	[Category(UITestCategories.ToolbarItem)]
+#endif
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Github, 6387,
+		"[Bug] [iOS] Crash When the First Toolbar Item Has an Icon and a Second Item Gets Added",
+		PlatformAffected.iOS)]
+	public partial class Issue6387 : TestContentPage
+	{
+#if APP
+		readonly ToolbarItem _item0;
+		readonly ToolbarItem _item1;
+#endif
+		public Issue6387()
+		{
+#if APP
+			InitializeComponent();
+
+			_item0 = new ToolbarItem("Item 0", null, ClearAndAddToolbarItems)
+            {
+                IconImageSource = ImageSource.FromResource("Xamarin.Forms.Controls.GalleryPages.crimson.jpg", typeof(Issue6387).GetTypeInfo().Assembly)
+            };
+            _item1 = new ToolbarItem("Item 1", null, ClearAndAddToolbarItems)
+            {
+                // It doesn't matter if this item has an image or not.
+            };
+
+			ClearAndAddToolbarItems();
+#endif
+		}
+
+		protected override void Init()
+		{
+
+		}
+#if APP
+		void ClearAndAddToolbarItems()
+		{
+			ToolbarItems.Clear();
+
+			ToolbarItems.Add(_item0);
+			ToolbarItems.Add(_item1);
+		}
+#endif
+	}
+}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems

@@ -1796,6 +1796,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Issue13577.xaml.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue14505.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue14505-II.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Issue6387.xaml.cs" />
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Bugzilla22229.xaml">
@@ -2279,6 +2280,9 @@
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Issue13577.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Include="$(MSBuildThisFileDirectory)Issue6387.xaml">
+      <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+    </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Bugzilla27417Xaml.xaml">
@@ -2799,7 +2803,7 @@
   <ItemGroup>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Issue13037.xaml">
       <SubType>Designer</SubType>
-      <Generator>MSBuild:Compile</Generator>
+      <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Issue2447.xaml">
       <SubType>Designer</SubType>

Xamarin.Forms.Platform.iOS/Extensions/ToolbarItemExtensions.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel;
+using System.Threading.Tasks;
 using CoreGraphics;
 using UIKit;
 using PointF = CoreGraphics.CGPoint;
@@ -23,6 +24,7 @@ public static UIBarButtonItem ToUIBarButtonItem(this ToolbarItem item, bool forc
 
 		sealed class PrimaryToolbarItem : UIBarButtonItem
 		{
+			bool _disposed;
 			readonly bool _forceName;
 			readonly ToolbarItem _item;
 
@@ -32,7 +34,7 @@ public PrimaryToolbarItem(ToolbarItem item, bool forceName)
 				_item = item;
 
 				if (item.IconImageSource != null && !item.IconImageSource.IsEmpty && !forceName)
-					UpdateIconAndStyle();
+					Device.BeginInvokeOnMainThread(async () => { await UpdateIconAndStyleAsync(); });
 				else
 					UpdateTextAndStyle();
 				UpdateIsEnabled();
@@ -50,11 +52,15 @@ public PrimaryToolbarItem(ToolbarItem item, bool forceName)
 			protected override void Dispose(bool disposing)
 			{
 				if (disposing)
+				{
 					_item.PropertyChanged -= OnPropertyChanged;
+					_disposed = true;
+				}
+
 				base.Dispose(disposing);
 			}
 
-			void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
+			async void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 			{
 				if (e.PropertyName == MenuItem.IsEnabledProperty.PropertyName)
 					UpdateIsEnabled();
@@ -68,7 +74,7 @@ void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 					if (!_forceName)
 					{
 						if (_item.IconImageSource != null && !_item.IconImageSource.IsEmpty)
-							UpdateIconAndStyle();
+							await UpdateIconAndStyleAsync();
 						else
 							UpdateTextAndStyle();
 					}
@@ -79,8 +85,11 @@ void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 					this.SetAccessibilityLabel(_item);
 			}
 
-			async void UpdateIconAndStyle()
+			async Task UpdateIconAndStyleAsync()
 			{
+				if (_disposed)
+					return;
+
 				Image = await _item.IconImageSource.GetNativeImageAsync();
 				Style = UIBarButtonItemStyle.Plain;
 			}
@@ -100,13 +109,14 @@ void UpdateTextAndStyle()
 
 		sealed class SecondaryToolbarItem : UIBarButtonItem
 		{
+			bool _disposed;
 			readonly ToolbarItem _item;
 
 			public SecondaryToolbarItem(ToolbarItem item) : base(new SecondaryToolbarItemContent())
 			{
 				_item = item;
 				UpdateText();
-				UpdateIcon();
+				Device.BeginInvokeOnMainThread(async () => { await UpdateIconAsync(); });
 				UpdateIsEnabled();
 
 				((SecondaryToolbarItemContent)CustomView).TouchUpInside += (sender, e) => ((IMenuItemController)_item).Activate();
@@ -122,16 +132,20 @@ public SecondaryToolbarItem(ToolbarItem item) : base(new SecondaryToolbarItemCon
 			protected override void Dispose(bool disposing)
 			{
 				if (disposing)
+				{
 					_item.PropertyChanged -= OnPropertyChanged;
+					_disposed = true;
+				}
+
 				base.Dispose(disposing);
 			}
 
-			void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
+			async void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 			{
 				if (e.PropertyName == MenuItem.TextProperty.PropertyName)
 					UpdateText();
 				else if (e.PropertyName == MenuItem.IconImageSourceProperty.PropertyName)
-					UpdateIcon();
+					await UpdateIconAsync();
 				else if (e.PropertyName == MenuItem.IsEnabledProperty.PropertyName)
 					UpdateIsEnabled();
 				else if (e.PropertyName == AutomationProperties.HelpTextProperty.PropertyName)
@@ -140,8 +154,11 @@ void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 					this.SetAccessibilityLabel(_item);
 			}
 
-			async void UpdateIcon()
+			async Task UpdateIconAsync()
 			{
+				if (_disposed)
+					return;
+
 				UIImage image = null;
 				if (_item.IconImageSource != null && !_item.IconImageSource.IsEmpty)
 				{