如何通过动画xamarin forms增加和减少flex布局的高度

using Xamarin.Forms;

public class MyPage : ContentPage
{
    private FlexLayout flexLayout;

    public MyPage()
    {
        flexLayout = new FlexLayout
        {
            Direction = FlexDirection.Column,
            JustifyContent = FlexJustify.SpaceAround,
            AlignItems = FlexAlignItems.Center,
            BackgroundColor = Color.LightGray,
            HeightRequest = 200 // 初始高度
        };

        var buttonIncreaseHeight = new Button
        {
            Text = "增加高度",
            Command = new Command(IncreaseHeight)
        };

        var buttonDecreaseHeight = new Button
        {
            Text = "减少高度",
            Command = new Command(DecreaseHeight)
        };

        flexLayout.Children.Add(buttonIncreaseHeight);
        flexLayout.Children.Add(buttonDecreaseHeight);

        Content = flexLayout;
    }

    private async void IncreaseHeight()
    {
        await flexLayout.LayoutTo(new Rectangle(flexLayout.X, flexLayout.Y, flexLayout.Width, flexLayout.Height + 100), 250, Easing.Linear);
    }

    private async void DecreaseHeight()
    {
        await flexLayout.LayoutTo(new Rectangle(flexLayout.X, flexLayout.Y, flexLayout.Width, flexLayout.Height - 100), 250, Easing.Linear);
    }
}