Mhawker/ttb updates

Microsoft.Toolkit.Uwp.SampleApp/SamplePages/TabView/TabViewPage.xaml.cs

@@ -69,5 +69,5 @@ private void Tabs_TabDraggedOutside(object sender, TabDraggedOutsideEventArgs e)
             TabViewNotification.Show("Tore Tab '" + str + "' Outside of TabView.", 2000);
         }
         #pragma warning restore CS0618 // Type or member is obsolete
-    }    
+    }
 }

Microsoft.Toolkit.Uwp.SampleApp/SamplePages/TokenizingTextBox/TokenizingTextBoxXaml.bind

@@ -16,7 +16,7 @@
       <controls:TokenizingTextBox
           x:Name="TokenBox"
           PlaceholderText="Add Actions"
-          QueryIcon="{ex:SymbolIconSource Glyph=Setting, FontSize=16}"
+          QueryIcon="{ex:SymbolIconSource Glyph=Setting}"
           MaxHeight="104"
           HorizontalAlignment="Stretch"
           TextMemberPath="Text"
@@ -52,7 +52,7 @@
             PlaceholderText="Select Names"
             MaxHeight="104"
             HorizontalAlignment="Stretch"
-            QueryIcon="{ex:SymbolIconSource Glyph=Find, FontSize=16}"
+            QueryIcon="{ex:SymbolIconSource Glyph=Find}"
             TextMemberPath="Text"
             TokenDelimiter=","
             IsItemClickEnabled="True">

Microsoft.Toolkit.Uwp.UI.Controls/TokenizingTextBox/TokenizingTextBox.cs

@@ -8,6 +8,8 @@
 using System.Threading.Tasks;
 using Microsoft.Toolkit.Uwp.Deferred;
 using Microsoft.Toolkit.Uwp.Extensions;
+using Microsoft.Toolkit.Uwp.UI.Extensions;
+using Microsoft.Toolkit.Uwp.UI.Helpers;
 using Windows.System;
 using Windows.UI.Core;
 using Windows.UI.Xaml;
@@ -435,6 +437,8 @@ internal async Task AddTokenAsync(object data, bool? atEnd = null)
             last?._autoSuggestTextBox.Focus(FocusState.Keyboard);
 
             TokenItemAdded?.Invoke(this, data);
+
+            GuardAgainstPlaceholderTextLayoutIssue();
         }
 
         private void UpdateCurrentTextEdit(PretokenStringContainer edit)
@@ -475,7 +479,34 @@ private async Task<bool> RemoveTokenAsync(TokenizingTextBoxItem item, object dat
 
             TokenItemRemoved?.Invoke(this, data);
 
+            GuardAgainstPlaceholderTextLayoutIssue();
+
             return true;
         }
+
+        private void GuardAgainstPlaceholderTextLayoutIssue()
+        {
+            // If the *PlaceholderText is visible* on the last AutoSuggestBox, it can incorrectly layout itself
+            // when the *ASB has focus*. We think this is an optimization in the platform, but haven't been able to
+            // isolate a straight-reproduction of this issue outside of this control (though we have eliminated
+            // most Toolkit influences like ASB/TextBox Style, the InterspersedObservableCollection, etc...).
+            // The only Toolkit component involved here should be WrapPanel (which is a straight-forward Panel).
+            // We also know the ASB itself is adjusting it's size correctly, it's the inner component.
+            //
+            // To combat this issue:
+            //   We toggle the visibility of the Placeholder ContentControl in order to force it's layout to update properly
+            var placeholder = ContainerFromItem(_lastTextEdit).FindDescendantByName("PlaceholderTextContentPresenter");
+
+            if (placeholder?.Visibility == Visibility.Visible)
+            {
+                placeholder.Visibility = Visibility.Collapsed;
+
+                // After we ensure we've hid the control, make it visible again (this is inperceptable to the user).
+                _ = CompositionTargetHelper.ExecuteAfterCompositionRenderingAsync(() =>
+                {
+                    placeholder.Visibility = Visibility.Visible;
+                });
+            }
+        }
     }
 }

Microsoft.Toolkit.Uwp.UI.Controls/TokenizingTextBox/TokenizingTextBox.xaml

@@ -12,7 +12,7 @@
     <Thickness x:Key="TokenizingTextBoxPresenterMargin">0,0,6,0</Thickness>
     <x:Double x:Key="TokenizingTextBoxTokenSpacing">2</x:Double>
     <Thickness x:Key="TextControlBorderThemeThicknessFocused">2</Thickness>
-
+    
     <controls:TokenizingTextBoxStyleSelector x:Key="TokenizingTextBoxStyleSelector"
                                              TextStyle="{StaticResource TokenizingTextBoxItemTextStyle}"
                                              TokenStyle="{StaticResource TokenizingTextBoxItemTokenStyle}"/>

Microsoft.Toolkit.Uwp.UI.Controls/TokenizingTextBox/TokenizingTextBoxItem.AutoSuggestBox.cs

@@ -101,6 +101,15 @@ private void OnApplyTemplateAutoSuggestBox(AutoSuggestBox auto)
                 // Setup a binding to the QueryIcon of the Parent if we're the last box.
                 if (Content is PretokenStringContainer str && str.IsLast)
                 {
+                    // Workaround for https://github.com/microsoft/microsoft-ui-xaml/issues/2568
+                    if (Owner.QueryIcon is FontIconSource fis &&
+                        fis.ReadLocalValue(FontIconSource.FontSizeProperty) == DependencyProperty.UnsetValue)
+                    {
+                        // This can be expensive, could we optimize?
+                        // Also, this is changing the FontSize on the IconSource (which could be shared?)
+                        fis.FontSize = Owner.TryFindResource("TokenizingTextBoxIconFontSize") as double? ?? 16;
+                    }
+
                     var iconBinding = new Binding()
                     {
                         Source = Owner,

Microsoft.Toolkit.Uwp.UI.Controls/TokenizingTextBox/TokenizingTextBoxItem.AutoSuggestBox.xaml

@@ -4,7 +4,8 @@
 
     <!--<Thickness x:Key="ButtonPadding">8,4,8,5</Thickness> Not sure if we'll also need this later-->
     <Thickness x:Key="TextControlThemePadding">10,3,6,6</Thickness><!-- Need local copy of this, as including WinUI overrides this to something that adds too much padding for our inner box -->
-
+    <x:Double x:Key="TokenizingTextBoxIconFontSize">16</x:Double><!-- 'Example' hard-coded currently in link:TokenizingTextBoxItem.AutoSuggestBox.cs#L110, but can be overwritten in developer's resources as 'normal' -->
+
     <!--#region Button Styles -->
     <Style x:Key="TokenizingTextBoxDeleteButtonStyle"
            TargetType="Button">
@@ -15,12 +16,14 @@
                           Background="{ThemeResource TextControlButtonBackground}"
                           BorderBrush="{ThemeResource TextControlButtonBorderBrush}"
                           BorderThickness="{TemplateBinding BorderThickness}">
+                        <!-- FontSize is ignored here, see https://github.com/microsoft/microsoft-ui-xaml/issues/2568 -->
+                        <!-- Set in code-behind link:TokenizingTextBoxItem.AutoSuggestBox.cs#L104 -->
                         <TextBlock x:Name="GlyphElement"
                                    HorizontalAlignment="Center"
                                    VerticalAlignment="Center"
                                    AutomationProperties.AccessibilityView="Raw"
                                    FontFamily="{ThemeResource SymbolThemeFontFamily}"
-                                   FontSize="{ThemeResource AutoSuggestBoxIconFontSize}"
+                                   FontSize="{ThemeResource TokenizingTextBoxIconFontSize}"
                                    FontStyle="Normal"
                                    Foreground="{ThemeResource TextControlButtonForeground}"
                                    Text="&#xE10A;" />
@@ -290,17 +293,12 @@
     <Style x:Key="TokenizingTextBoxItemTextStyle" TargetType="controls:TokenizingTextBoxItem">
         <Setter Property="Background" Value="{ThemeResource SystemControlBackgroundChromeMediumLowBrush}" />
         <Setter Property="BorderBrush" Value="{ThemeResource SystemControlTransparentBrush}" />
-        <!-- <Setter Property="BorderThickness" Value="{StaticResource TokenizingTextBoxItemBorderThickness}" />
-        <Setter Property="HorizontalContentAlignment" Value="{StaticResource TokenizingTextBoxItemHorizontalContentAlignment}" />
-        <Setter Property="Padding" Value="{StaticResource TokenizingTextBoxItemPadding}" />
-        <Setter Property="VerticalContentAlignment" Value="{StaticResource TokenizingTextBoxItemVerticalContentAlignment}" />-->
         <Setter Property="IsTabStop" Value="False" />
         <Setter Property="UseSystemFocusVisuals" Value="False" />
         <Setter Property="MinWidth" Value="128" />
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="controls:TokenizingTextBoxItem">
-                    <!-- TODO: Thinking we should just give a reference to the parent for each item when we construct the container? -->
                     <AutoSuggestBox Name="PART_AutoSuggestBox"
                                     UpdateTextOnSelect="False"
                                     DisplayMemberPath="{Binding Path=Owner.DisplayMemberPath, RelativeSource={RelativeSource Mode=TemplatedParent}}"
@@ -311,7 +309,6 @@
                                     Style="{StaticResource SystemAutoSuggestBoxStyle}"
                                     Text="{Binding Text, Mode=TwoWay}"
                                     TextBoxStyle="{StaticResource TokenizingTextBoxTextBoxStyle}"/>
-                    <!-- TODO: Visual State to style autosuggestbox based on focus? -->
                 </ControlTemplate>
             </Setter.Value>
         </Setter>

Microsoft.Toolkit.Uwp.UI/Extensions/Tree/LogicalTree.cs

@@ -286,5 +286,37 @@ private static string ContentPropertySearch(Type type)
 
             return ContentPropertySearch(type.GetTypeInfo().BaseType);
         }
+
+        /// <summary>
+        /// Provides a WPF compatible version of TryFindResource to provide a static resource lookup.
+        /// If the key is not found in the current element's resources, the logical tree is then searched element-by-element to look for the resource in each element's resources.
+        /// If none of the elements contain the resource, the Application's resources are then searched.
+        /// <seealso href="https://docs.microsoft.com/en-us/dotnet/api/system.windows.frameworkelement.tryfindresource"/>
+        /// <seealso href="https://docs.microsoft.com/en-us/dotnet/desktop-wpf/fundamentals/xaml-resources-define#static-resource-lookup-behavior"/>
+        /// </summary>
+        /// <param name="start"><see cref="FrameworkElement"/> to start searching for Resource.</param>
+        /// <param name="resourceKey">Key to search for.</param>
+        /// <returns>Requested resource or null.</returns>
+        public static object TryFindResource(this FrameworkElement start, object resourceKey)
+        {
+            object value = null;
+            var current = start;
+
+            // Look in our dictionary and then walk-up parents
+            while (current != null)
+            {
+                if (current.Resources?.TryGetValue(resourceKey, out value) == true)
+                {
+                    return value;
+                }
+
+                current = current.Parent as FrameworkElement;
+            }
+
+            // Finally try application resources.
+            Application.Current?.Resources?.TryGetValue(resourceKey, out value);
+
+            return value;
+        }
     }
 }

Microsoft.Toolkit.Uwp.UI/Helpers/CompositionTargetHelper.cs

@@ -0,0 +1,50 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.Threading.Tasks;
+using Microsoft.Toolkit.Diagnostics;
+using Windows.UI.Xaml.Media;
+
+namespace Microsoft.Toolkit.Uwp.UI.Helpers
+{
+    /// <summary>
+    /// Provides helpers for the <see cref="CompositionTarget"/> class.
+    /// </summary>
+    public static class CompositionTargetHelper
+    {
+        /// <summary>
+        /// Provides a method to execute code after the rendering pass is completed.
+        /// <seealso href="https://github.com/microsoft/microsoft-ui-xaml/blob/c045cde57c5c754683d674634a0baccda34d58c4/dev/dll/SharedHelpers.cpp#L399"/>
+        /// </summary>
+        /// <param name="action">Action to be executed after render pass</param>
+        /// <returns>Awaitable Task</returns>
+        public static Task<bool> ExecuteAfterCompositionRenderingAsync(Action action)
+        {
+            Guard.IsNotNull(action, nameof(action));
+
+            var taskCompletionSource = new TaskCompletionSource<bool>();
+
+            try
+            {
+                void Callback(object sender, object args)
+                {
+                    CompositionTarget.Rendering -= Callback;
+
+                    action();
+
+                    taskCompletionSource.SetResult(true);
+                }
+
+                CompositionTarget.Rendering += Callback;
+            }
+            catch (Exception e)
+            {
+                taskCompletionSource.SetException(e); // Note this can just sometimes be a wrong thread exception, see WinUI function notes.
+            }
+
+            return taskCompletionSource.Task;
+        }
+    }
+}