I try to paint in my WPF PDF viewer.
If no PDF is loaded, this works.

When i opened a file, the painted things are not longer visible.

I would like that my red rectangle drawn (and displayed), even if a file is opened.
That’s my OnRender Method, what i’m doing wrong?
`
`
public class PDFView : PDFViewWPF
{
// …
#region Drawing
protected override void OnRender(DrawingContext drawingContext)
{
Trace.WriteLine(“PDFView: OnRender”);
base.OnRender(drawingContext);
drawingContext.DrawRectangle(Brushes.Red, new Pen(Brushes.Black, 0), new System.Windows.Rect(150, 150, 100, 100));
}
#endregion Drawing
// …
}
`
`
|
The answer is given by Chales Petzold here.
His answer is ‘don’t know why’, however a comment correctly suggests that setting the window’s Background to transparent fixes the bug.
It is possible that Grid generates this problem. Default Window contains a Grid element.
|
On Wednesday, May 23, 2012 12:57:39 AM UTC-7, David wrote:
I try to paint in my WPF PDF viewer.
If no PDF is loaded, this works.
When i opened a file, the painted things are not longer visible.
I would like that my red rectangle drawn (and displayed), even if a file is opened.
That’s my OnRender Method, what i’m doing wrong?
`
`
public class PDFView : PDFViewWPF
{
// …
#region Drawing
protected override void OnRender(DrawingContext drawingContext)
{
Trace.WriteLine(“PDFView: OnRender”);
base.OnRender(drawingContext);
drawingContext.DrawRectangle(Brushes.Red, new Pen(Brushes.Black, 0), new System.Windows.Rect(150, 150, 100, 100));
}
#endregion Drawing
// …
}
`
`