source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/Charts/LiveTooltips/LiveTooltipAdorner.cs @ 13834

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Documents;
using System.Windows;
using System.Windows.Media;
using System.Windows.Input;
using System.Windows.Media.Effects;
using System.Windows.Controls;
using System.Windows.Shapes;

namespace Microsoft.Research.DynamicDataDisplay.Charts
{
  public class LiveToolTipAdorner : Adorner
  {
    private Canvas canvas = new Canvas { IsHitTestVisible = false };
    private readonly VisualCollection visualChildren;
    public LiveToolTipAdorner(UIElement adornedElement, LiveToolTip tooltip)
      : base(adornedElement)
    {
      visualChildren = new VisualCollection(this);

      adornedElement.MouseLeave += adornedElement_MouseLeave;
      adornedElement.MouseEnter += adornedElement_MouseEnter;
      adornedElement.PreviewMouseMove += adornedElement_MouseMove;
      //FrameworkElement frAdornedElement = (FrameworkElement)adornedElement;
      //frAdornedElement.SizeChanged += frAdornedElement_SizeChanged;

      this.liveTooltip = tooltip;

      tooltip.Visibility = Visibility.Hidden;

      canvas.Children.Add(liveTooltip);
      AddLogicalChild(canvas);
      visualChildren.Add(canvas);

      Unloaded += LiveTooltipAdorner_Unloaded;
    }

    //void frAdornedElement_SizeChanged(object sender, SizeChangedEventArgs e)
    //{
    //    grid.Width = e.NewSize.Width;
    //    grid.Height = e.NewSize.Height;

    //    InvalidateMeasure();
    //}

    void LiveTooltipAdorner_Unloaded(object sender, RoutedEventArgs e)
    {
      canvas.Children.Remove(liveTooltip);
    }

    void adornedElement_MouseLeave(object sender, MouseEventArgs e)
    {
      liveTooltip.Visibility = Visibility.Hidden;
    }

    void adornedElement_MouseEnter(object sender, MouseEventArgs e)
    {
      liveTooltip.Visibility = Visibility.Visible;
    }

    Point mousePosition;
    private void adornedElement_MouseMove(object sender, MouseEventArgs e)
    {
      liveTooltip.Visibility = Visibility.Visible;
      mousePosition = e.GetPosition(AdornedElement);
      InvalidateMeasure();
    }

    private void ArrangeTooltip()
    {
      Size tooltipSize = liveTooltip.DesiredSize;

      Point location = mousePosition;
      location.Offset(-tooltipSize.Width / 2, -tooltipSize.Height - 1);

      liveTooltip.Arrange(new Rect(location, tooltipSize));
    }

    LiveToolTip liveTooltip;
    public LiveToolTip LiveTooltip
    {
      get { return liveTooltip; }
    }

    #region Overrides

    protected override Visual GetVisualChild(int index)
    {
      return visualChildren[index];
    }

    protected override int VisualChildrenCount
    {
      get { return visualChildren.Count; }
    }

    protected override Size MeasureOverride(Size constraint)
    {
      foreach (UIElement item in visualChildren)
      {
        item.Measure(constraint);
      }

      liveTooltip.Measure(constraint);

      return base.MeasureOverride(constraint);
    }

    protected override Size ArrangeOverride(Size finalSize)
    {
      foreach (UIElement item in visualChildren)
      {
        item.Arrange(new Rect(item.DesiredSize));
      }

      ArrangeTooltip();

      return finalSize;
    }

    #endregion // end of overrides
  }
}