//------------------------------------------------------
//
// Protected Methods
//
//------------------------------------------------------
#region Protected Methods
/// <summary>
/// Render override to render the composition adorner here.
/// </summary>
protected override void OnRender(DrawingContext drawingContext)
{
// Get the matrix from AdornedElement to the visual parent to get the transformed
// start/end point
Visual parent2d = VisualTreeHelper.GetParent(this.AdornedElement) as Visual;
if (parent2d == null)
{
return;
}
GeneralTransform transform = AdornedElement.TransformToAncestor(parent2d);
if (transform == null)
{
return;
}
// Please note that we do the highlight adornment for the CONVERTED text only
// for Simplified Chinese IMEs. Doing this uniformly across all IMEs wasnt possible
// because it was noted that some of them (viz. Japanese) werent being consistent
// about this attribute.
bool isChinesePinyin = chinesePinyin.Equals(InputLanguageManager.Current.CurrentInputLanguage.IetfLanguageTag);
// Render the each of the composition string attribute from the attribute ranges.
for (int i = 0; i < _attributeRanges.Count; i++)
{
DoubleCollection dashArray;
// Get the composition attribute range from the attribute range lists
AttributeRange attributeRange = (AttributeRange)_attributeRanges[i];
// Skip the rendering composition lines if the composition line doesn't exist.
if (attributeRange.CompositionLines.Count == 0)
{
continue;
}
// Set the line bold and squiggle
bool lineBold = attributeRange.TextServicesDisplayAttribute.IsBoldLine ? true : false;
bool squiggle = false;
bool hasVirtualSelection = (attributeRange.TextServicesDisplayAttribute.AttrInfo & UnsafeNativeMethods.TF_DA_ATTR_INFO.TF_ATTR_TARGET_CONVERTED) != 0;
Brush selectionBrush = null;
double selectionOpacity = -1;
Pen selectionPen = null;
if (isChinesePinyin && hasVirtualSelection)
{
DependencyObject owner = _textView.TextContainer.Parent;
selectionBrush = (Brush)owner.GetValue(TextBoxBase.SelectionBrushProperty);
selectionOpacity = (double)owner.GetValue(TextBoxBase.SelectionOpacityProperty);
}
// Set the line height and cluse gap value that base on the ratio of text height
double height = attributeRange.Height;
double lineHeight = height * (lineBold ? BoldLineHeightRatio : NormalLineHeightRatio);
double clauseGap = height * ClauseGapRatio;
// Create Pen for drawing the composition lines with the specified line color
Pen pen = new Pen(new SolidColorBrush(Colors.Black), lineHeight);
// Set the pen style that based on IME's composition line style
switch (attributeRange.TextServicesDisplayAttribute.LineStyle)
{
case UnsafeNativeMethods.TF_DA_LINESTYLE.TF_LS_DOT:
// Add the dot length and specify the start/end line cap as the round
dashArray = new DoubleCollection();
dashArray.Add(DotLength);
dashArray.Add(DotLength);
pen.DashStyle = new DashStyle(dashArray, 0);
pen.DashCap = System.Windows.Media.PenLineCap.Round;
pen.StartLineCap = System.Windows.Media.PenLineCap.Round;
pen.EndLineCap = System.Windows.Media.PenLineCap.Round;
// Update the line height for the dot line. Dot line will be more thickness than
// other line to show it clearly.
lineHeight = height * (lineBold ? BoldDotLineHeightRatio : NormalDotLineHeightRatio);
break;
case UnsafeNativeMethods.TF_DA_LINESTYLE.TF_LS_DASH:
double dashLength = height * (lineBold ? BoldDashRatio : NormalDashRatio);
double dashGapLength = height * (lineBold ? BoldDashGapRatio : NormalDashGapRatio);
// Add the dash and dash gap legth
dashArray = new DoubleCollection();
dashArray.Add(dashLength);
dashArray.Add(dashGapLength);
pen.DashStyle = new DashStyle(dashArray, 0);
pen.DashCap = System.Windows.Media.PenLineCap.Round;
pen.StartLineCap = System.Windows.Media.PenLineCap.Round;
pen.EndLineCap = System.Windows.Media.PenLineCap.Round;
break;
case UnsafeNativeMethods.TF_DA_LINESTYLE.TF_LS_SOLID:
pen.StartLineCap = System.Windows.Media.PenLineCap.Round;
pen.EndLineCap = System.Windows.Media.PenLineCap.Round;
break;
case UnsafeNativeMethods.TF_DA_LINESTYLE.TF_LS_SQUIGGLE:
squiggle = true;
break;
}
double halfLineHeight = lineHeight / 2;
// Draw the each of the composition line
for (int j = 0; j < attributeRange.CompositionLines.Count; j++)
{
CompositionLine compositionLine = (CompositionLine)attributeRange.CompositionLines[j];
// Get the start/end point for composition adorner.
// Currently Text doesn't aware of the spaceroom for the drawing of the composition
// adorner(like as normal/bold dot/line/squggle), so we should draw the composition adorners
// to the closest area of the bottom text.
Point startPoint = new Point(compositionLine.StartPoint.X + clauseGap, compositionLine.StartPoint.Y - halfLineHeight);
Point endPoint = new Point(compositionLine.EndPoint.X - clauseGap, compositionLine.EndPoint.Y - halfLineHeight);
// Apply composition line color which is actually the foreground of text as well
pen.Brush = new SolidColorBrush(compositionLine.LineColor);
// Apply matrix to start/end point
//
transform.TryTransform(startPoint, out startPoint);
transform.TryTransform(endPoint, out endPoint);
if (isChinesePinyin && hasVirtualSelection)
{
Rect rect = Rect.Union(compositionLine.StartRect, compositionLine.EndRect);
rect = transform.TransformBounds(rect);
drawingContext.PushOpacity(selectionOpacity);
drawingContext.DrawRectangle(selectionBrush, selectionPen, rect);
drawingContext.Pop();
}
if (squiggle)
{
// Draw the squiggle line with using of the PathFigure and DrawGemetry.
// We may revisit this logic to render the smooth squiggle line.
Point pathPoint = new Point(startPoint.X, startPoint.Y - halfLineHeight);
double squiggleGap = halfLineHeight;
PathFigure pathFigure = new PathFigure();
pathFigure.StartPoint = pathPoint;
int indexPoint = 0;
while (indexPoint < ((endPoint.X - startPoint.X) / (squiggleGap)))
{
if (indexPoint % 4 == 0 || indexPoint % 4 == 3)
{
pathPoint = new Point(pathPoint.X + squiggleGap, pathPoint.Y + halfLineHeight);
pathFigure.Segments.Add(new LineSegment(pathPoint, true));
}
else if (indexPoint % 4 == 1 || indexPoint % 4 == 2)
{
pathPoint = new Point(pathPoint.X + squiggleGap, pathPoint.Y - halfLineHeight);
pathFigure.Segments.Add(new LineSegment(pathPoint, true));
}
indexPoint++;
}
PathGeometry pathGeometry = new PathGeometry();
pathGeometry.Figures.Add(pathFigure);
// Draw the composition line with the squiggle
drawingContext.DrawGeometry(null, pen, pathGeometry);
}
else
{
drawingContext.DrawLine(pen, startPoint, endPoint);
}
}
}
}