/// <summary>
/// Invalidates this instance.
/// </summary>
public void Invalidate()
{
if (this.rendered)
{
return;
}
this.rendered = true;
this.OnPropertyChanged("Width");
this.OnPropertyChanged("Height");
this.OnPropertyChanged("ImageSource");
int desiredWidth = Width;
int desiredHeight = Height;
if (this.tokenSource != null)
{
this.tokenSource.Cancel();
}
this.tokenSource = new CancellationTokenSource();
this.tokenSource.Token.ThrowIfCancellationRequested();
Dispatcher dispatcher = Dispatcher.CurrentDispatcher;
this.image = new byte[desiredWidth * desiredHeight * 4];
RenderingSettings renderingSettings = new RenderingSettings();
renderingSettings.DrawText = this.DrawText;
renderingSettings.DrawImages = this.DrawImages;
renderingSettings.DrawPaths = this.DrawPaths;
renderingSettings.DrawAnotations = this.DrawAnnotations;
renderingSettings.AnnotationRenderingSettings = new RenderingSettings();
renderingSettings.AnnotationRenderingSettings.DrawText = this.DrawAnnotationsText;
// Uncomment to not draw annotations
// renderingSettings.DrawAnotations = false;
Task renderingTask = new Task(() => this.page.RenderAsBytes(desiredWidth, desiredHeight, this.image, renderingSettings));
this.task = Task.Factory.StartNew(
() =>
{
renderingTask.Start();
while (!(renderingTask.IsCompleted || renderingTask.IsCanceled || renderingTask.IsFaulted))
{
if (tokenSource.IsCancellationRequested)
{
renderingSettings.CancelRendering();
this.rendered = false;
this.task = null;
this.source = null;
this.tokenSource = null;
this.image = null;
break;
}
renderingTask.Wait(1000);
dispatcher.Invoke(DispatcherPriority.DataBind, new Action(() =>
{
source = BitmapSource.Create(this.Width, this.Height, 72, 72, PixelFormats.Bgra32, null,
image, 4 * this.Width);
this.OnPropertyChanged("ImageSource");
}));
}
this.image = null;
dispatcher.Invoke(DispatcherPriority.Background, new Action(() =>
{
if (this.source != null)
{
this.source.Freeze();
}
}));
GC.Collect();
}, this.tokenSource.Token);
}
