silverlight - WP7 : Suppressing XNA touch input when handled by Silverlight?

Question

我在Mango中有一个XNA + Silverlight游戏:主要是XNA，顶部还有一些Silverlight UI。我遇到的问题是，当您按下按钮或与Silverlight控件进行交互时，触摸信息仍会传递到XNA游戏循环中。您如何抑制这一点？

Answer 1

安排了一个类为我做跟踪。页面加载后(在Loaded处理程序中)，创建此页面并为其指定根元素(以便它可以附加到LayoutUpdated事件)。注册在游戏过程中可能会覆盖游戏表面的所有控件。然后只需调用TouchesControl并传递触摸位置即可确定是否应该忽略该点。它缓存控件的区域并在布局更新时对其进行更新。

应该适用于移动，更改大小或折叠/展开的矩形元素。

public class ControlTouchTracker
{
    private List<FrameworkElement> controls = new List<FrameworkElement>();
    private Dictionary<FrameworkElement, ControlRegion> controlBounds = new Dictionary<FrameworkElement, ControlRegion>();

    public ControlTouchTracker(FrameworkElement rootElement)
    {
        rootElement.LayoutUpdated += this.OnLayoutUpdated;
    }

    public void RegisterControl(FrameworkElement control)
    {
        controls.Add(control);
    }

    public void RemoveControl(FrameworkElement control)
    {
        controls.Remove(control);
        controlBounds.Remove(control);
    }

    private void OnLayoutUpdated(object sender, EventArgs e)
    {
        foreach (Control control in this.controls)
        {
            this.RefreshControlBounds(control);
        }
    }

    private void RefreshControlBounds(FrameworkElement control)
    {
        if (this.ControlIsVisible(control))
        {
            try
            {
                GeneralTransform controlTransform = control.TransformToVisual(Application.Current.RootVisual);
                Point offset = controlTransform.Transform(new Point(0, 0));

                this.controlBounds[control] = new ControlRegion
                {
                    Left = (float)offset.X,
                    Right = (float)(offset.X + control.ActualWidth),
                    Top = (float)offset.Y,
                    Bottom = (float)(offset.Y + control.ActualHeight)
                };
            }
            catch (ArgumentException)
            {
            }
        }
        else
        {
            if (this.controlBounds.ContainsKey(control))
            {
                this.controlBounds.Remove(control);
            }
        }
    }

    private bool ControlIsVisible(FrameworkElement control)
    {
        // End case
        if (control == null)
        {
            return true;
        }

        if (control.Visibility == Visibility.Collapsed)
        {
            return false;
        }

        return this.ControlIsVisible(control.Parent as FrameworkElement);
    }

    public bool TouchesControl(Vector2 touchPosition)
    {
        foreach (ControlRegion region in this.controlBounds.Values)
        {
            if (touchPosition.X >= region.Left && touchPosition.X <= region.Right &&
                touchPosition.Y >= region.Top && touchPosition.Y <= region.Bottom)
            {
                return true;
            }
        }

        return false;
    }

    public class ControlRegion
    {
        public float Left { get; set; }
        public float Right { get; set; }
        public float Top { get; set; }
        public float Bottom { get; set; }
    }
}

(编辑)更新了示例，以与更改 Visibility的父元素一起使用。