WCS/Plugins/Wcs/Plugin.Cowain.Wcs/Controls/GridColumnAnimationBehavior.cs

using Avalonia.Animation.Easings;
using Avalonia.Animation;
using Avalonia;
using Avalonia.Controls;
using Avalonia.Xaml.Interactivity;
using Irihi.Avalonia.Shared.Helpers;
using Avalonia.Controls.Presenters;
using Avalonia.Data;
using Avalonia.Media;
using Avalonia.Styling;


namespace Plugin.Cowain.Wcs.Controls;

public class GridColumnAnimationBehavior : Behavior<Grid>
{
    private IDisposable? _columnSubscription;

    public static readonly StyledProperty<int> GridColumnProperty =
        AvaloniaProperty.Register<GridColumnAnimationBehavior, int>(
            nameof(GridColumn),
            defaultBindingMode: BindingMode.TwoWay);

    public int GridColumn
    {
        get => GetValue(GridColumnProperty);
        set => SetValue(GridColumnProperty, value);
    }

    protected override void OnAttached()
    {
        base.OnAttached();

        if (AssociatedObject is not null)
        {
            // 开始监听布局更新或直接触发初始动画
            AssociatedObject.AttachedToVisualTree += HandleAttached;
        }
    }

    protected override void OnDetaching()
    {
        if (AssociatedObject is not null)
        {
            AssociatedObject.AttachedToVisualTree -= HandleAttached;
        }

        _columnSubscription?.Dispose();
        base.OnDetaching();
    }

    private void HandleAttached(object? sender, VisualTreeAttachmentEventArgs e)
    {
        if (AssociatedObject is Grid grid && grid.Parent is ContentPresenter contentPresenter)
        {
            // 使用绑定监听Grid.Column变化
            _columnSubscription = contentPresenter.GetObservable(Grid.ColumnProperty)
                .Subscribe(column =>
                {
                    if (column != GridColumn)
                    {
                        AnimateColumnChange(grid, column, GridColumn);
                    }
                });
        }
    }

    private void AnimateColumnChange(Grid grid, int fromColumn, int toColumn)
    {
        var contentPresenter = grid.Parent as ContentPresenter;
        if (contentPresenter == null) return;

        // 创建水平移动动画
        var transform = new TranslateTransform();
        contentPresenter.RenderTransform = transform;

        var _animation = new Animation
        {
            Duration = TimeSpan.FromSeconds(0.3),
            Easing = new CubicEaseInOut(),
            Children =
                {
                    new KeyFrame
                    {
                        Cue = new Cue(0d),
                        Setters =
                        {
                            new Setter
                            {
                                Property = TranslateTransform.XProperty,
                                Value = fromColumn * -grid.ColumnDefinitions[fromColumn].ActualWidth
                            }
                        }
                    },
                    new KeyFrame
                    {
                        Cue = new Cue(1d),
                        Setters =
                        {
                            new Setter
                            {
                                Property = TranslateTransform.XProperty,
                                Value = toColumn * -grid.ColumnDefinitions[toColumn].ActualWidth
                            }
                        }
                    }
                }
        };
        _animation.RunAsync(contentPresenter);
    }
}