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I want to create a custom control in C#. But every time I have to fully redraw my control, it flickers, even if I use double buffering (drawing to an Image first, and blitting that).

How do I eliminate flicker when I have to fully redraw?

Lars Truijens
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user7305
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4 Answers4

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You could try putting the following in your constructor after the InitiliseComponent call. 

SetStyle(ControlStyles.OptimizedDoubleBuffer | 
         ControlStyles.UserPaint |
         ControlStyles.AllPaintingInWmPaint, true);

EDIT:

If you're giving this a go, if you can, remove your own double buffering code and just have the control draw itself in response to the appropriate virtual methods being called.

Julien Roncaglia
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Shaun Austin
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  • I usually put that stuff in before the Application.Run, but yea this I think is the best solution to this problem. – Quibblesome Sep 15 '08 at 16:38
  • I agree. I've also found a good url in another flicker-related question. http://www.codeproject.com/KB/graphics/DoubleBuffering.aspx – user7305 Sep 15 '08 at 17:12
  • I've tried soooo mant different solutions but this fixes it!! +1 for telling to put it after InitializeComponent(); !! xoxoxo – Emily Dec 27 '16 at 09:45
8

I pulled this from a working C# program. Other posters have syntax errors and clearly copied from C++ instead of C#

SetStyle(ControlStyles.OptimizedDoubleBuffer | 
                        ControlStyles.UserPaint |
                        ControlStyles.AllPaintingInWmPaint, true);
Brad Bruce
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1

It may be good enough to just call 

SetStyle(ControlStyles::UserPaint | ControlStyles::AllDrawingInWmPaint, true);

The flickering you are seeing most likely because Windows draws the background of the control first (via WM_ERASEBKGND), then asks your control to do whatever drawing you need to do (via WM_PAINT). By disabling the background paint and doing all painting in your OnPaint override can eliminate the problem in 99% of the cases without the need to use all the memory needed for double buffering.

Eric W
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0

You say you've tried double buffering, but then you say drawing to an Image first and blitting that. Have you tried setting DoubleBuffered = true in the constructor rather than doing it yourself with an Image?

Grokys
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