如何在Xamarin.Forms中制作可折叠面板？

using Xamarin.Forms;

namespace YourNamespace
{
    public class CollapsiblePanel : View
    {
        public static readonly BindableProperty IsExpandedProperty =
            BindableProperty.Create(nameof(IsExpanded), typeof(bool), typeof(CollapsiblePanel), false);

        public bool IsExpanded
        {
            get { return (bool)GetValue(IsExpandedProperty); }
            set { SetValue(IsExpandedProperty, value); }
        }

        public CollapsiblePanel()
        {
            var header = new ContentView
            {
                // 设置头部部分的内容
                Content = new Label { Text = "Header" },
                GestureRecognizers = { new TapGestureRecognizer { Command = new Command(ToggleExpanded) } }
            };

            var content = new ContentView
            {
                // 设置内容部分的内容
                Content = new Label { Text = "Content" }
            };

            // 创建一个垂直布局容器，用于包含头部和内容部分
            var layout = new StackLayout();
            layout.Children.Add(header);
            layout.Children.Add(content);

            // 设置自定义控件的内容为垂直布局容器
            Content = layout;
        }

        private void ToggleExpanded()
        {
            // 切换展开状态
            IsExpanded = !IsExpanded;

            // 执行动画效果
            var content = ((StackLayout)Content).Children[1];
            content.FadeTo(IsExpanded ? 1 : 0, 250, Easing.Linear);
            content.TranslateTo(0, IsExpanded ? 0 : -content.Height, 250, Easing.Linear);
        }
    }
}

using Xamarin.Forms;

namespace YourNamespace
{
    public class MainPage : ContentPage
    {
        public MainPage()
        {
            var collapsiblePanel = new CollapsiblePanel();
            Content = new StackLayout
            {
                Children = { collapsiblePanel }
            };
        }
    }
}