C# Avalonia 15- Animation- CodeAnimation

例子展现了两种设置动画的方法，各位自行选择。

 CodeAnimation.axaml代码

<Window xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        Height="369.6" Width="454.4"
        x:Class="AvaloniaUI.CodeAnimation"
        Title="CodeAnimation">
    <Grid RowDefinitions="*,*,*">
        <Button Padding="10" Name="cmdGrow" Click="cmdGrow_Click" Height="40" Width="160"
                HorizontalAlignment="Center"
                VerticalAlignment="Center"
                HorizontalContentAlignment="Center"        
                VerticalContentAlignment="Center">
            Click and Make Me Grow
        </Button>

        <Button Grid.Row="1" Padding="10" Click="cmdShrink_Click"
            HorizontalAlignment="Center"
                VerticalAlignment="Center"
                HorizontalContentAlignment="Center"
                VerticalContentAlignment="Center">
            Shrink It Back
        </Button>

        <Button Grid.Row="2" Padding="10" Name="cmdGrowIncrementally" Click="cmdGrowIncrementally_Click"
            HorizontalAlignment="Center" VerticalAlignment="Center" Width="240">
            Click and Make Me Grow (Incrementally)
        </Button>
    </Grid>
</Window>

CodeAnimation.axaml.cs代码

using Avalonia;
using Avalonia.Animation;
using Avalonia.Animation.Easings;
using Avalonia.Controls;
using Avalonia.Interactivity;
using Avalonia.Markup.Xaml;
using Avalonia.Styling;
using System;
using System.Reactive.Linq;
using System.Threading;

namespace AvaloniaUI;

public partial class CodeAnimation : Window
{
    public CodeAnimation()
    {
        InitializeComponent();
        // 在代码里给按钮设置 Transition
        cmdGrow.Transitions = new Transitions
        {
            new DoubleTransition
            {
                Property = Button.WidthProperty,
                Duration = TimeSpan.FromSeconds(5),
                Easing = new SineEaseInOut()
            },
            new DoubleTransition
            {
                Property = Button.HeightProperty,
                Duration = TimeSpan.FromSeconds(5),
                Easing = new SineEaseInOut()
            }
        };

    }

    private void cmdGrow_Click(object? sender, RoutedEventArgs e)
    {
        // 设置目标值，相当于 WPF 的 To
        cmdGrow.Width = this.Width - 100;
        cmdGrow.Height = (this.Height - 100) / 3;

        cmdGrow.GetObservable(Button.WidthProperty).Subscribe(v =>
        {
            if (v == this.Width - 100)
            {
                Console.WriteLine("Completed");
            }
        });
    }

    private void cmdShrink_Click(object? sender, RoutedEventArgs e)
    {
        cmdGrow.Width = 160;
        cmdGrow.Height = 40;
    }

    private void cmdGrowIncrementally_Click(object? sender, RoutedEventArgs e)
    {
        var animation = new Animation
        {
            Duration = TimeSpan.FromSeconds(0.5),
            Children =
            {
                new KeyFrame
                {
                    Cue = new Cue(1),
                    Setters =
                    {
                        new Setter(Button.WidthProperty, cmdGrowIncrementally.Width + 10)
                    }
                }
            },
            FillMode = FillMode.Forward
        };
        _ = animation.RunAsync(cmdGrowIncrementally);
    }
}

运行效果