/// <summary>
/// Scans text line for matching image comment signature, then adds new or updates existing image adornment
/// </summary>
private void CreateVisuals(ITextViewLine line, int lineNumber)
{
#pragma warning disable 219
bool imageDetected = false; // useful for tracing
#pragma warning restore 219
string lineText = line.Extent.GetText();
string imageUrl;
double scale;
string matchedText;
int matchIndex = ImageCommentParser.Match(_contentTypeName, lineText, out matchedText);
if (matchIndex >= 0)
{
// Get coordinates of text
int start = line.Extent.Start.Position + matchIndex;
int end = line.Start + (line.Extent.Length - 1);
var span = new SnapshotSpan(_view.TextSnapshot, Span.FromBounds(start, end));
Exception xmlParseException;
ImageCommentParser.TryParse(matchedText, out imageUrl, out scale, out xmlParseException);
if (xmlParseException != null)
{
if (Images.ContainsKey(lineNumber))
{
_layer.RemoveAdornment(Images[lineNumber]);
Images.Remove(lineNumber);
}
_errorTags.Add(new TagSpan <ErrorTag>(span, new ErrorTag("XML parse error", getErrorMessage(xmlParseException))));
return;
}
MyImage image = null;
Exception imageLoadingException = null;
// Check for and update existing image
MyImage existingImage = Images.ContainsKey(lineNumber) ? Images[lineNumber] : null;
if (existingImage != null)
{
image = existingImage;
if (existingImage.Url == imageUrl && existingImage.Scale != scale) // URL same but scale changed
{
existingImage.Scale = scale;
}
else if (existingImage.Url != imageUrl) // URL different, so set new source
{
existingImage.TrySet(imageUrl, scale, out imageLoadingException);
}
}
else // No existing image, so create new one
{
image = new MyImage(_variableExpander);
image.TrySet(imageUrl, scale, out imageLoadingException);
Images.Add(lineNumber, image);
}
// Position image and add as adornment
if (imageLoadingException == null)
{
Geometry g = _view.TextViewLines.GetMarkerGeometry(span);
if (g == null) // Exceptional case when image dimensions are massive (e.g. specifying very large scale factor)
{
throw new InvalidOperationException("Couldn't get source code line geometry. Is the loaded image massive?");
}
double textLeft = g.Bounds.Left;
double textBottom = line.TextBottom;
Canvas.SetLeft(image, textLeft);
Canvas.SetTop(image, textBottom);
// Add image to editor view
try
{
_layer.RemoveAdornment(image);
_layer.AddAdornment(AdornmentPositioningBehavior.TextRelative, line.Extent, null, image, null);
}
catch (Exception ex)
{
// No expected exceptions, so tell user something is wrong.
ExceptionHandler.Notify(ex, true);
}
}
else
{
if (Images.ContainsKey(lineNumber))
{
Images.Remove(lineNumber);
}
_errorTags.Add(new TagSpan <ErrorTag>(span, new ErrorTag("Trouble loading image", getErrorMessage(imageLoadingException))));
}
imageDetected = true;
}
else
{
if (Images.ContainsKey(lineNumber))
{
Images.Remove(lineNumber);
}
}
}
