如何在Xamarin窗体中设置等于屏幕高度的BoxView或Frame height？

using Xamarin.Forms;

public class MyPage : ContentPage
{
    public MyPage()
    {
        var screenHeight = DeviceDisplay.MainDisplayInfo.Height;

        var boxView = new BoxView
        {
            HeightRequest = screenHeight,
            BackgroundColor = Color.Red
        };

        // 或者使用 Frame 控件
        /*
        var frame = new Frame
        {
            HeightRequest = screenHeight,
            BackgroundColor = Color.Red,
            Content = new Label { Text = "Hello World" }
        };
        */

        Content = new StackLayout
        {
            Children = { boxView }
        };
    }
}