From e7b99842bc139160b0be3821d653f15f87609484 Mon Sep 17 00:00:00 2001
From: rabbitism <dongbin@irihi.tech>
Date: Sat, 17 Feb 2024 15:16:49 +0800
Subject: [PATCH] feat: add a sample for date.

---
 .../Ursa.Demo/Pages/NumberDisplayerDemo.axaml |  1 +
 .../NumberDisplayerDemoViewModel.cs           |  3 ++
 .../NumberDisplayer/NumberDisplayer.cs        | 32 +++++++++++++++++--
 3 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/demo/Ursa.Demo/Pages/NumberDisplayerDemo.axaml b/demo/Ursa.Demo/Pages/NumberDisplayerDemo.axaml
index 0a7ec19..21f67cc 100644
--- a/demo/Ursa.Demo/Pages/NumberDisplayerDemo.axaml
+++ b/demo/Ursa.Demo/Pages/NumberDisplayerDemo.axaml
@@ -12,5 +12,6 @@
         <Button Command="{Binding IncreaseCommand}" >Change</Button>
         <u:Int32Displayer Value="{Binding Value}"></u:Int32Displayer>
         <u:DoubleDisplayer Value="{Binding DoubleValue}" StringFormat="N2"></u:DoubleDisplayer>
+        <u:DateDisplay Value="{Binding DateValue}" StringFormat="yyyy-MM-dd"></u:DateDisplay>
     </StackPanel>
 </UserControl>
diff --git a/demo/Ursa.Demo/ViewModels/NumberDisplayerDemoViewModel.cs b/demo/Ursa.Demo/ViewModels/NumberDisplayerDemoViewModel.cs
index 0032e47..befdd5b 100644
--- a/demo/Ursa.Demo/ViewModels/NumberDisplayerDemoViewModel.cs
+++ b/demo/Ursa.Demo/ViewModels/NumberDisplayerDemoViewModel.cs
@@ -9,12 +9,14 @@ public partial class NumberDisplayerDemoViewModel: ObservableObject
 {
     [ObservableProperty] private int _value;
     [ObservableProperty] private double _doubleValue;
+    [ObservableProperty] private DateTime _dateValue;
     public ICommand IncreaseCommand { get; }
     public NumberDisplayerDemoViewModel()
     {
         IncreaseCommand = new RelayCommand(OnChange);
         Value = 0;
         DoubleValue = 0d;
+        DateValue = DateTime.Now;
     }
 
     private void OnChange()
@@ -22,5 +24,6 @@ public partial class NumberDisplayerDemoViewModel: ObservableObject
         Random r = new Random();
         Value = r.Next(int.MaxValue);
         DoubleValue = r.NextDouble() * 100000;
+        DateValue = DateTime.Today.AddDays(r.Next(1000));
     }
 }
\ No newline at end of file
diff --git a/src/Ursa/Controls/NumberDisplayer/NumberDisplayer.cs b/src/Ursa/Controls/NumberDisplayer/NumberDisplayer.cs
index 946d58e..3beff1e 100644
--- a/src/Ursa/Controls/NumberDisplayer/NumberDisplayer.cs
+++ b/src/Ursa/Controls/NumberDisplayer/NumberDisplayer.cs
@@ -91,6 +91,8 @@ public abstract class NumberDisplayer<T>: NumberDisplayerBase
             Setters = { new Setter{Property = InternalValueProperty } }
         });
         Animation.SetAnimator(_animation.Children[0].Setters[0], GetAnimator());
+        Animation.SetAnimator(_animation.Children[1].Setters[0], GetAnimator());
+        InternalValue = Value;
     }
 
     private void OnDurationChanged(AvaloniaPropertyChangedEventArgs<TimeSpan> args)
@@ -101,11 +103,12 @@ public abstract class NumberDisplayer<T>: NumberDisplayerBase
 
     protected virtual void OnValueChanged(T? oldValue, T? newValue)
     {
+        if (_animation is null) return;
         _cts.Cancel();
         _cts = new CancellationTokenSource();
-        (_animation?.Children[0].Setters[0] as Setter)!.Value = oldValue;
-        (_animation?.Children[1].Setters[0] as Setter)!.Value = newValue;
-        _animation?.RunAsync(this, _cts.Token);
+        (_animation.Children[0].Setters[0] as Setter)!.Value = oldValue;
+        (_animation.Children[1].Setters[0] as Setter)!.Value = newValue;
+        _animation.RunAsync(this, _cts.Token);
     }
 
     protected abstract InterpolatingAnimator<T> GetAnimator();
@@ -159,3 +162,26 @@ public class DoubleDisplayer : NumberDisplayer<double>
         return value.ToString(StringFormat);
     }
 }
+
+public class DateDisplay : NumberDisplayer<DateTime>
+{
+    protected override Type StyleKeyOverride { get; } = typeof(NumberDisplayerBase);
+
+    protected override InterpolatingAnimator<DateTime> GetAnimator()
+    {
+        return new DateAnimator();
+    }
+
+    private class DateAnimator : InterpolatingAnimator<DateTime>
+    {
+        public override DateTime Interpolate(double progress, DateTime oldValue, DateTime newValue)
+        {
+            return oldValue + TimeSpan.FromTicks((long)((newValue - oldValue).Ticks * progress));
+        }
+    }
+
+    protected override string GetString(DateTime value)
+    {
+        return value.ToString(StringFormat);
+    }
+}