feat(ui): spin the arrow on "Check now" and "Check again"

src/Filee.App/Controls/Spin.cs

@@ -0,0 +1,71 @@
+// Turns an icon while Spin.IsActive is true (About: Check now, Engines: Check again). It is done in code, not with a
+// XAML animation: a Style.Animations on RotateTransform.Angle in Soft.axaml stopped the ComboBox chevron from flipping.
+// With "Reduce animations" on the icon does not turn.
+
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Media;
+using Avalonia.Threading;
+using Filee.App.Services;
+
+namespace Filee.App.Controls;
+
+public static class Spin
+{
+    private const double TurnMilliseconds = 900;
+
+    public static readonly AttachedProperty<bool> IsActiveProperty =
+        AvaloniaProperty.RegisterAttached<Control, bool>("IsActive", typeof(Spin));
+
+    public static bool GetIsActive(Control control) => control.GetValue(IsActiveProperty);
+    public static void SetIsActive(Control control, bool value) => control.SetValue(IsActiveProperty, value);
+
+    private sealed class State
+    {
+        public DispatcherTimer? Timer;
+    }
+
+    private static readonly ConditionalWeakTable<Control, State> States = new();
+
+    static Spin()
+    {
+        IsActiveProperty.Changed.AddClassHandler<Control>((control, e) =>
+        {
+            if (e.NewValue is true)
+                Start(control);
+            else
+                Stop(control);
+        });
+    }
+
+    private static void Start(Control control)
+    {
+        if (!Motion.Enabled)
+            return;
+        var state = States.GetOrCreateValue(control);
+        if (state.Timer is not null)
+            return;
+
+        var clock = Stopwatch.StartNew();
+        var timer = new DispatcherTimer(DispatcherPriority.Render) { Interval = TimeSpan.FromMilliseconds(16) };
+        timer.Tick += (_, _) =>
+        {
+            var angle = clock.Elapsed.TotalMilliseconds % TurnMilliseconds / TurnMilliseconds * 360;
+            control.RenderTransform = new RotateTransform(angle); // the origin is the middle of the icon
+        };
+        state.Timer = timer;
+        control.DetachedFromVisualTree += (_, _) => Stop(control);
+        timer.Start();
+    }
+
+    private static void Stop(Control control)
+    {
+        if (!States.TryGetValue(control, out var state) || state.Timer is null)
+            return;
+        state.Timer.Stop();
+        state.Timer = null;
+        control.RenderTransform = null;
+    }
+}

src/Filee.App/Styles/Soft.axaml

@@ -427,17 +427,14 @@
     <Setter Property="Foreground" Value="{DynamicResource AccentStrongBrush}" />
   </Style>
 
-  <!-- ToggleSwitch: M3 track, knob and hover color -->
+  <!-- ToggleSwitch: M3 track, knob and hover color. No hover scale on the control itself: its label is part of it, so the text would grow with the switch. -->
   <Style Selector="Window.material-you ToggleSwitch">
     <Setter Property="Transitions">
       <Transitions>
         <TransformOperationsTransition Property="RenderTransform" Duration="0:0:0.18" Easing="{StaticResource SoftEase}" />
       </Transitions>
     </Setter>
   </Style>
-  <Style Selector="Window.material-you ToggleSwitch:pointerover">
-    <Setter Property="RenderTransform" Value="scale(1.02)" />
-  </Style>
   <Style Selector="Window.material-you ToggleSwitch /template/ Border#SwitchKnobBounds">
     <Setter Property="CornerRadius" Value="{DynamicResource SoftRadiusPill}" />
     <Setter Property="Transitions">

src/Filee.App/ViewModels/Pages/AboutPageViewModel.cs

@@ -65,8 +65,18 @@ private void OnUpdatesChanged(object? sender, System.ComponentModel.PropertyChan
             ShowUpdateState(_updates.LatestVersion);
     }
 
+    /// <summary>A check can finish in a blink; the arrow on "Check now" keeps turning for at least this long so it reads as checking.</summary>
+    private static readonly TimeSpan MinimumCheckTime = TimeSpan.FromMilliseconds(900);
+
     [RelayCommand]
-    private async Task CheckNow() => ShowUpdateState(await _updates.CheckAsync(), afterCheck: true);
+    private async Task CheckNow()
+    {
+        // With "Reduce animations" on there is no arrow turning, so there is nothing to hold the result back for.
+        var minimumSpin = Task.Delay(Motion.Enabled ? MinimumCheckTime : TimeSpan.Zero);
+        var newer = await _updates.CheckAsync();
+        await minimumSpin;
+        ShowUpdateState(newer, afterCheck: true);
+    }
 
     /// <summary>Downloads and runs the new installer, which updates Filee in place (a portable copy opens the download page).</summary>
     [RelayCommand]

src/Filee.App/ViewModels/Pages/EnginesPageViewModel.cs

@@ -160,12 +160,18 @@ private void Reload()
     [RelayCommand]
     private void MoveDown(EngineItemViewModel item) => Move(item, +1);
 
+    /// <summary>The check can be over in a blink; the arrow on "Check again" keeps turning for at least this long so it reads as checking.</summary>
+    private static readonly TimeSpan MinimumRecheckTime = TimeSpan.FromMilliseconds(900);
+
     [RelayCommand]
-    private void Recheck()
+    private async Task Recheck()
     {
+        // With "Reduce animations" on there is no arrow turning, so there is nothing to hold the result back for.
+        var minimumSpin = Task.Delay(Motion.Enabled ? MinimumRecheckTime : TimeSpan.Zero);
         EngineEnvironment.ForgetSystemCopies(); // a tool installed meanwhile is found
         _downloads.RefreshStatus();
         _catalog.Refresh();
+        await minimumSpin;
     }
 
     private void Move(EngineItemViewModel item, int delta)

src/Filee.App/Views/Pages/AboutPage.axaml

@@ -62,7 +62,14 @@
           <TextBlock Classes="h2" Text="{DynamicResource about.updates}" />
           <ToggleSwitch Content="{DynamicResource general.check_updates}" IsChecked="{Binding CheckForUpdates}" />
           <WrapPanel>
-            <Button Content="{DynamicResource general.check_now}" Command="{Binding CheckNowCommand}" Margin="0,0,10,0" />
+            <Button Command="{Binding CheckNowCommand}" Margin="0,0,10,0">
+              <StackPanel Orientation="Horizontal" Spacing="6">
+                <!-- Turns while the check runs (Spin.IsActive follows CheckNowCommand.IsRunning; the code is in Controls/Spin.cs). -->
+                <PathIcon c:Spin.IsActive="{Binding CheckNowCommand.IsRunning}"
+                          Width="13" Height="13" Data="{StaticResource Icon.Refresh}" />
+                <TextBlock Text="{DynamicResource general.check_now}" />
+              </StackPanel>
+            </Button>
             <Button Classes="accent" Command="{Binding DownloadUpdateCommand}" IsVisible="{Binding UpdateAvailable}" Margin="0,0,10,0">
               <StackPanel Orientation="Horizontal" Spacing="6">
                 <PathIcon Width="13" Height="13" Data="{StaticResource Icon.Download}" />

src/Filee.App/Views/Pages/EnginesPage.axaml

@@ -2,6 +2,7 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              xmlns:vm="using:Filee.App.ViewModels.Pages"
              xmlns:svc="using:Filee.App.Services"
+             xmlns:c="using:Filee.App.Controls"
              x:Class="Filee.App.Views.Pages.EnginesPage"
              x:DataType="vm:EnginesPageViewModel">
   <UserControl.Styles>
@@ -25,7 +26,9 @@
       <DockPanel>
         <Button DockPanel.Dock="Right" Command="{Binding RecheckCommand}">
           <StackPanel Orientation="Horizontal" Spacing="6">
-            <PathIcon Width="13" Height="13" Data="{StaticResource Icon.Refresh}" />
+            <!-- Turns while the recheck runs (Spin.IsActive follows RecheckCommand.IsRunning; the code is in Controls/Spin.cs). -->
+            <PathIcon c:Spin.IsActive="{Binding RecheckCommand.IsRunning}"
+                      Width="13" Height="13" Data="{StaticResource Icon.Refresh}" />
             <TextBlock Text="{DynamicResource engines.recheck}" />
           </StackPanel>
         </Button>