Merge branch 'main' of https://github.com/Redth/Maui.VirtualListView

Author: Redth

Sample/VirtualListViewSample/MainViewModel.cs

@@ -15,9 +15,11 @@ public MainViewModel()
 	MusicDataAdapter adapter;
 
 	[RelayCommand]
-	async Task Refresh()
+	async Task Refresh(Action completion)
 	{
 		await Task.Delay(3000);
+		System.Diagnostics.Debug.WriteLine("Refresh Complete");
+		completion?.Invoke();
 	}
 
 	[RelayCommand]

VirtualListView/Apple/VirtualListViewHandler.ios.maccatalyst.cs

@@ -39,9 +39,7 @@ protected override UICollectionView CreatePlatformView()
 		refreshControl.AddTarget(new EventHandler((s, a) =>
 		{
 			refreshControl.BeginRefreshing();
-			VirtualView?.Refresh();
-			refreshControl.EndRefreshing();
-
+			VirtualView?.Refresh(() => refreshControl.EndRefreshing());
 		}), UIControlEvent.ValueChanged);
 
 		collectionView.AddSubview(refreshControl);

VirtualListView/Controls/VirtualListView.cs

@@ -111,16 +111,16 @@ public Maui.SelectionMode SelectionMode
 
 	public event EventHandler<SelectedItemsChangedEventArgs> OnSelectedItemsChanged;
 
-	public event EventHandler<EventArgs> OnRefresh;
+	public event EventHandler<RefreshEventArgs> OnRefresh;
 
-	void IVirtualListView.Refresh()
+	void IVirtualListView.Refresh(Action completionCallback)
 	{
 		if (RefreshCommand != null && RefreshCommand.CanExecute(null))
 		{
-			RefreshCommand.Execute(null);
+			RefreshCommand.Execute(completionCallback);
 		}
 
-		OnRefresh?.Invoke(this, EventArgs.Empty);
+		OnRefresh?.Invoke(this, new RefreshEventArgs(completionCallback));
 	}
 
 	public ICommand RefreshCommand

VirtualListView/IVirtualListView.cs

@@ -26,7 +26,7 @@ public interface IVirtualListView : IView
 
 	Color RefreshAccentColor { get; }
 
-	void Refresh();
+	void Refresh(Action completionCallback);
 
 	bool IsRefreshEnabled { get; }
 

VirtualListView/Platforms/Android/RvAdapter.cs

@@ -24,6 +24,8 @@ public override int ItemCount
 	internal RvAdapter(Context context, VirtualListViewHandler handler, PositionalViewSelector positionalViewSelector)
 	{
 		Context = context;
+		HasStableIds = false;
+
 		this.handler = handler;
 		this.positionalViewSelector = positionalViewSelector;
 	}
@@ -79,7 +81,8 @@ public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int positi
 		}
 	}
 
-	List<string> cachedReuseIds = new List<string>();
+	Dictionary<string, int> cachedReuseIds = new ();
+	int reuseIdCount = 100;
 
 	public override int GetItemViewType(int position)
 	{
@@ -103,19 +106,20 @@ public override int GetItemViewType(int position)
 
 		lock (lockObj)
 		{
-			vt = cachedReuseIds.IndexOf(reuseId) + 1;
-			if (vt <= 0)
+			if (!cachedReuseIds.TryGetValue(reuseId, out var reuseIdNumber))
 			{
-				cachedReuseIds.Add(reuseId);
-				vt = cachedReuseIds.Count;
+				reuseIdNumber = ++reuseIdCount;
+				cachedReuseIds.Add(reuseId, reuseIdNumber);
 			}
+
+			vt = reuseIdNumber;
 		}
 
 		return vt;
 	}
 
 	public override long GetItemId(int position)
-		=> position;
+		=> RecyclerView.NoId;
 
 	public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
 	{
@@ -146,9 +150,9 @@ public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int
 
 	public void Reset()
 	{
-		lock (lockObj)
-		{
-			cachedReuseIds.Clear();
-		}
+		//lock (lockObj)
+		//{
+		//	cachedReuseIds.Clear();
+		//}
 	}
 }

VirtualListView/Platforms/Android/VirtualListViewHandler.android.cs

@@ -37,8 +37,7 @@ protected override void ConnectHandler(FrameLayout nativeView)
 	{
 		swipeRefreshLayout.SetOnRefreshListener(new SrlRefreshListener(() =>
 		{
-			VirtualView?.Refresh();
-			swipeRefreshLayout.Refreshing = false;
+			VirtualView?.Refresh(() => swipeRefreshLayout.Refreshing = false);
 		}));
 
 		layoutManager = new LinearLayoutManager(Context);

VirtualListView/RefreshEventArgs.cs

@@ -0,0 +1,12 @@
+namespace Microsoft.Maui;
+
+public class RefreshEventArgs : EventArgs
+{
+	public RefreshEventArgs(Action completion)
+		: base()
+	{
+		Complete = completion;
+	}
+
+	public readonly Action Complete;
+}

VirtualListView/SelectedItemsChangedEventArgs.cs

@@ -14,4 +14,4 @@ public SelectedItemsChangedEventArgs(
 	public IReadOnlyList<ItemPosition> PreviousSelection { get; }
 
 	public IReadOnlyList<ItemPosition> NewSelection { get; }
-}
+}