/// <summary>
/// Stroke Invalidated event handler
/// </summary>
private void OnStrokeInvalidated(object sender, EventArgs eventArgs)
{
System.Diagnostics.Debug.Assert(_strokes.IndexOf(sender as Stroke) != -1);
// Find the visual associated with the changed stroke.
StrokeVisual visual;
Stroke stroke = (Stroke)sender;
if (_visuals.TryGetValue(stroke, out visual) == false)
{
throw new System.ArgumentException(SR.Get(SRID.UnknownStroke1));
}
// The original value of IsHighligher and Color are cached in StrokeVisual.
// if (IsHighlighter value changed or (IsHighlighter == true and not changed and color changed)
// detach and re-attach the corresponding visual;
// otherwise Invalidate the corresponding StrokeVisual
if (visual.CachedIsHighlighter != stroke.DrawingAttributes.IsHighlighter ||
(stroke.DrawingAttributes.IsHighlighter &&
StrokeRenderer.GetHighlighterColor(visual.CachedColor) != StrokeRenderer.GetHighlighterColor(stroke.DrawingAttributes.Color)))
{
// The change requires reparenting the visual in the tree.
DetachVisual(visual);
AttachVisual(visual, false /*buildingStrokeCollection*/);
// Update the cached values
visual.CachedIsHighlighter = stroke.DrawingAttributes.IsHighlighter;
visual.CachedColor = stroke.DrawingAttributes.Color;
}
// Update the visual.
visual.Update();
}
/// <summary>
/// Finds a container for a new visual based on the drawing attributes
/// of the stroke rendered into that visual.
/// </summary>
/// <param name="drawingAttributes">drawing attributes</param>
/// <returns>visual</returns>
private ContainerVisual GetContainerVisual(DrawingAttributes drawingAttributes)
{
System.Diagnostics.Debug.Assert(drawingAttributes != null);
HighlighterContainerVisual hcVisual;
if (drawingAttributes.IsHighlighter)
{
// For a highlighter stroke, the color.A is neglected.
Color color = StrokeRenderer.GetHighlighterColor(drawingAttributes.Color);
if ((_highlighters == null) || (_highlighters.TryGetValue(color, out hcVisual) == false))
{
if (_highlighters == null)
{
_highlighters = new Dictionary <Color, HighlighterContainerVisual>();
}
hcVisual = new HighlighterContainerVisual(color);
hcVisual.Opacity = StrokeRenderer.HighlighterOpacity;
_highlightersRoot.Children.Add(hcVisual);
_highlighters.Add(color, hcVisual);
}
else if (VisualTreeHelper.GetParent(hcVisual) == null)
{
_highlightersRoot.Children.Add(hcVisual);
}
return(hcVisual);
}
else
{
return(_regularInkVisuals);
}
}
/// <summary>
/// Render the StrokeCollection under the specified DrawingContext.
/// </summary>
/// <param name="context"></param>
public void Draw(DrawingContext context)
{
if (null == context)
{
throw new System.ArgumentNullException("context");
}
//The verification of UI context affinity is done in Stroke.Draw()
List <Stroke> solidStrokes = new List <Stroke>();
Dictionary <Color, List <Stroke> > highLighters = new Dictionary <Color, List <Stroke> >();
for (int i = 0; i < this.Count; i++)
{
Stroke stroke = this[i];
List <Stroke> strokes;
if (stroke.DrawingAttributes.IsHighlighter)
{
// It's very important to override the Alpha value so that Colors of the same RGB vale
// but different Alpha would be in the same list.
Color color = StrokeRenderer.GetHighlighterColor(stroke.DrawingAttributes.Color);
if (highLighters.TryGetValue(color, out strokes) == false)
{
strokes = new List <Stroke>();
highLighters.Add(color, strokes);
}
strokes.Add(stroke);
}
else
{
solidStrokes.Add(stroke);
}
}
foreach (List <Stroke> strokes in highLighters.Values)
{
context.PushOpacity(StrokeRenderer.HighlighterOpacity);
try
{
foreach (Stroke stroke in strokes)
{
stroke.DrawInternal(context, StrokeRenderer.GetHighlighterAttributes(stroke, stroke.DrawingAttributes),
false /*Don't draw selected stroke as hollow*/);
}
}
finally
{
context.Pop();
}
}
foreach (Stroke stroke in solidStrokes)
{
stroke.DrawInternal(context, stroke.DrawingAttributes, false /*Don't draw selected stroke as hollow*/);
}
}