From 1f2c020ff70cc8b70abc9e70f6bb0d987f0786fd Mon Sep 17 00:00:00 2001
From: Prathamesh Narkhede <pnarkhede@esri.com>
Date: Wed, 4 Sep 2024 16:46:45 -0700
Subject: [PATCH] Refactor BookmarksView for simplicity and performance

---
 .../BookmarksView/BookmarksView.cs            | 42 +++++--------------
 1 file changed, 11 insertions(+), 31 deletions(-)

diff --git a/src/Toolkit/Toolkit.Maui/BookmarksView/BookmarksView.cs b/src/Toolkit/Toolkit.Maui/BookmarksView/BookmarksView.cs
index 59342b348..b428968ec 100644
--- a/src/Toolkit/Toolkit.Maui/BookmarksView/BookmarksView.cs
+++ b/src/Toolkit/Toolkit.Maui/BookmarksView/BookmarksView.cs
@@ -24,7 +24,7 @@ namespace Esri.ArcGISRuntime.Toolkit.Maui;
 /// </summary>
 public class BookmarksView : TemplatedView
 {
-    private BookmarksViewDataSource _dataSource = new BookmarksViewDataSource();
+    private readonly BookmarksViewDataSource _dataSource = new();
     private const string _presentingViewName = "PresentingView";
 
     private static readonly DataTemplate DefaultDataTemplate;
@@ -33,18 +33,17 @@ public class BookmarksView : TemplatedView
     [DynamicDependency(nameof(Bookmark.Name), "Esri.ArcGISRuntime.Mapping.Bookmark", "Esri.ArcGISRuntime")]
     static BookmarksView()
     {
-        DefaultDataTemplate = new DataTemplate(() =>
-        {
-            var defaultLabel = new Label();
-            defaultLabel.SetBinding(Label.TextProperty, nameof(Bookmark.Name));
-            return defaultLabel;
-        });
+        string dataTemplate =
+            @"<DataTemplate xmlns=""http://schemas.microsoft.com/dotnet/2021/maui"">
+                <Label Text=""{Binding Name}"" />
+              </DataTemplate>";
+        DefaultDataTemplate = Microsoft.Maui.Controls.Xaml.Extensions.LoadFromXaml(new DataTemplate(), dataTemplate);
 
         string template =
             $@"<ControlTemplate xmlns=""http://schemas.microsoft.com/dotnet/2021/maui""
-                               xmlns:x=""http://schemas.microsoft.com/winfx/2009/xaml""
-                               xmlns:esriTK=""clr-namespace:Esri.ArcGISRuntime.Toolkit.Maui"">
-                <CollectionView x:Name=""{_presentingViewName}"" SelectionMode=""Single"" />
+                                xmlns:x=""http://schemas.microsoft.com/winfx/2009/xaml""
+                                xmlns:esriTK=""clr-namespace:Esri.ArcGISRuntime.Toolkit.Maui"">
+                <CollectionView x:Name=""{_presentingViewName}"" SelectionMode=""Single"" ItemTemplate=""{{TemplateBinding ItemTemplate}}"" />
              </ControlTemplate>";
         DefaultControlTemplate = Microsoft.Maui.Controls.Xaml.Extensions.LoadFromXaml(new ControlTemplate(), template);
     }
@@ -70,8 +69,8 @@ protected override void OnApplyTemplate()
         {
             view.SelectionChanged -= Internal_bookmarkSelected;
             view.SelectionChanged += Internal_bookmarkSelected;
+            view.ItemsSource = _dataSource;
         }
-        UpdatePresentingView();
     }
 
     /// <summary>
@@ -123,7 +122,7 @@ public GeoView? GeoView
     /// Identifies the <see cref="ItemTemplate" /> bindable property.
     /// </summary>
     public static readonly BindableProperty ItemTemplateProperty =
-        BindableProperty.Create(nameof(ItemTemplate), typeof(DataTemplate), typeof(BookmarksView), DefaultDataTemplate, BindingMode.OneWay, null, propertyChanged: ItemTemplateChanged);
+        BindableProperty.Create(nameof(ItemTemplate), typeof(DataTemplate), typeof(BookmarksView), DefaultDataTemplate, BindingMode.OneWay, null);
 
     /// <summary>
     /// Handles property changes for the <see cref="BookmarksOverride" /> bindable property.
@@ -143,15 +142,6 @@ private static void GeoViewChanged(BindableObject sender, object? oldValue, obje
         bookmarkView._dataSource.SetGeoView(newValue as GeoView);
     }
 
-    /// <summary>
-    /// Handles property changes for the <see cref="ItemTemplate" /> bindable property.
-    /// </summary>
-    private static void ItemTemplateChanged(BindableObject sender, object? oldValue, object? newValue)
-    {
-        BookmarksView bookmarksView = (BookmarksView)sender;
-        bookmarksView.UpdatePresentingView();
-    }
-
     /// <summary>
     /// Selects the bookmark and navigates to it in the associated <see cref="GeoView" />.
     /// </summary>
@@ -184,16 +174,6 @@ private void Internal_bookmarkSelected(object? sender, SelectionChangedEventArgs
         }
     }
 
-    private void UpdatePresentingView()
-    {
-        var collectionView = (CollectionView)GetTemplateChild(_presentingViewName);
-        if (collectionView is CollectionView view)
-        {
-            view.ItemTemplate = ItemTemplate;
-            view.ItemsSource = _dataSource;
-        }
-    }
-
     /// <summary>
     /// Raised whenever a bookmark is selected.
     /// </summary>