"Canvas does not allow drawing" - What is it?

"Canvas does not allow drawing" - What is it?

Post by Mock Loc » Thu, 04 Jan 2001 09:56:52



Sometimes, just sometimes, I get that message error on my application. What
does it mean? How can I solve this problem?

thanks

 
 
 

"Canvas does not allow drawing" - What is it?

Post by Earl F. Glyn » Thu, 04 Jan 2001 11:42:10



> Sometimes, just sometimes, I get that message error on my application. What
> does it mean? How can I solve this problem?

Try this link:

Msg 'Canvas does not allow drawing'
http://www.delphifaq.com/fq/q4053.shtml

--
efg


Overland Park, KS  USA

efg's Computer Lab:  http://www.efg2.com/Lab
Mirror:  http://homepages.borland.com/efg2lab/Default.htm

 
 
 

1. "Canvas does not allow drawing"

I get this "Canvas Does not allow drawing" exception when I try to do the
following:

TCanvas* aCanvas = new TCanvas();  //dynamically allocate a new TCanvas
DrawOn(aCanvas);  //do some drawing on it
Canvas->CopyRect(destRect, aCanvas, sourceRect);  //Try to paste the new
canvas onto a screen canvas.
I get the exception when I try to use CopyRect() to copy the new Canvas onto
something else.  Is this an acceptable practice?  I guess instead of
creating TCanvas objects I could create TBitmap objects, and use CopyRect()
with those like the documentation shows, but wouldn't using a TCanvas as the
source be less memory intensive (assuming that it is possible)?

Thanks,
-Mike

2. Visual Basic 5.0 palette manipulation

3. "The Parameter is Incorrect" and "Canvas does not allow drawing"

4. PoV-radiosity

5. "Canvas does not allow drawing"... with no canvas!

6. Animators in Hamilton, Ontario

7. Canvas does not allow drawing...

8. open inventor model editing

9. LoadFromResourceName and "Canvas does not allow drawing"

10. Canvas does not allow drawing.

11. Canvas does not allow drawing

12. Error: Canvas does not allow drawing

13. Canvas not allow drawing