improved animations

Author: fgsfds

src/Avalonia.Desktop/Controls/AnimatedWrapPanel.cs

@@ -9,6 +9,7 @@
              xmlns:ctrl="clr-namespace:Avalonia.Desktop.Controls"
              xmlns:in="clr-namespace:Common.Interfaces;assembly=BuildLauncher.Common.Common"
              x:DataType="vm:CampaignsViewModel"
+             AttachedToVisualTree="OnControlAttachedToVisualTree"
              x:Class="Avalonia.Desktop.Controls.CampaignsControl">
 
     <UserControl.Resources>
@@ -84,7 +85,6 @@
             </DataTemplate>
         </UserControl.DataTemplates>
 
-
         <Grid RowDefinitions="auto,*,auto" ColumnDefinitions="2*,*">
 
             <Grid ColumnDefinitions="auto,*,auto"
@@ -115,7 +115,7 @@
                      ItemsSource="{Binding CampaignsList}"
                      SelectedItem="{Binding SelectedAddon}"
                      PointerPressed="OnCampaignsListEmptySpaceClicked"
-                     ContainerPrepared="ListBox_ContainerPrepared"
+                     ContainerPrepared="OnListBoxContainerPrepared"
                      DragDrop.AllowDrop="True"
                      DragDrop.Drop="OnCampaignsListDrop">
 
@@ -173,7 +173,7 @@
 
                 <ListBox.ItemsPanel>
                     <ItemsPanelTemplate>
-                        <ctrl:AnimatedWrapPanel Orientation="Horizontal" ItemSpacing="3" LineSpacing="0"/>
+                        <WrapPanel Orientation="Horizontal" ItemSpacing="3" LineSpacing="0"/>
                     </ItemsPanelTemplate>
                 </ListBox.ItemsPanel>
 

src/Avalonia.Desktop/Controls/CampaignsControl.axaml

@@ -4,9 +4,13 @@
 using Avalonia.Desktop.Misc;
 using Avalonia.Desktop.ViewModels;
 using Avalonia.Input;
+using Avalonia.Rendering.Composition;
+using Avalonia.Rendering.Composition.Animations;
 using Common.Common.Helpers;
 using Common.Enums;
+using Common.Helpers;
 using Common.Interfaces;
+using CommunityToolkit.Diagnostics;
 using CommunityToolkit.Mvvm.Input;
 using Ports.Ports;
 using Ports.Providers;
@@ -24,6 +28,8 @@ public sealed partial class CampaignsControl : UserControl
     private readonly InstalledAddonsProvider _addonsProvider;
     private readonly BitmapsCache _bitmapsCache;
 
+    private ImplicitAnimationCollection? _implicitAnimations;
+
     public CampaignsControl()
     {
         InitializeComponent();
@@ -383,13 +389,59 @@ private async void OnCampaignsListDrop(object sender, DragEventArgs e)
         }
     }
 
-    private void ListBox_ContainerPrepared(object? sender, Avalonia.Controls.ContainerPreparedEventArgs e)
+    private void OnListBoxContainerPrepared(object? sender, ContainerPreparedEventArgs e)
+    {
+        if (e.Container is ListBoxItem item)
+        {
+            if (item.Content is SeparatorItem)
+            {
+                item.IsHitTestVisible = false;
+                item.Focusable = false;
+            }
+            else
+            {
+                if (_implicitAnimations != null)
+                {
+                    EnsureImplicitAnimationsAsync(item);
+                }
+            }
+        }
+    }
+
+    private void OnControlAttachedToVisualTree(object? sender, VisualTreeAttachmentEventArgs e)
     {
-        if (e.Container is ListBoxItem item &&
-            item.Content is SeparatorItem)
+        if (_implicitAnimations == null)
         {
-            item.IsHitTestVisible = false;
-            item.Focusable = false;
+            var compositor = ElementComposition.GetElementVisual(this)?.Compositor;
+
+            Guard.IsNotNull(compositor);
+
+            var offsetAnimation = compositor.CreateVector3KeyFrameAnimation();
+            offsetAnimation.Target = "Offset";
+            offsetAnimation.InsertExpressionKeyFrame(1.0f, "this.FinalValue");
+            offsetAnimation.Duration = TimeSpan.FromMilliseconds(400);
+
+            var animationGroup = compositor.CreateAnimationGroup();
+            animationGroup.Add(offsetAnimation);
+
+            _implicitAnimations = compositor.CreateImplicitAnimationCollection();
+            _implicitAnimations["Offset"] = animationGroup;
+        }
+    }
+
+    private async void EnsureImplicitAnimationsAsync(Control control)
+    {
+        for (int i = 0; i < 5; i++)
+        {
+            var visual = ElementComposition.GetElementVisual(control);
+
+            if (visual != null)
+            {
+                visual.ImplicitAnimations = _implicitAnimations;
+                return;
+            }
+
+            await Task.Delay(50).ConfigureAwait(true);
         }
     }
 }