Screen flicker issue

Question

I've got an issue where some computers (rarely) start to flicker when using our application. I found some odd code in the main form of our app:

    protected override CreateParams CreateParams
    {
        get
        {                
            var cp = base.CreateParams;
            cp.ExStyle |= 0x02000000;//composite window. Composite windows do not render/flickr when controls are born.  This speeds up loading.
            return cp;
        }
    }

The code appears to be sourced from an online source where they warn:

You should be aware of the fact, though, that this only works in environments where all control painting(within the hierarchy) is done within WM_PAINT. Applications using other/asynchronous means of rendering into a control within the hierarchy will likely have theirs problems with this solution causing unwanted behavior.

What exactly is WM_PAINT? Do they mean all controls need to be painted via win32 API calls or is this what happens normally in a Load event?

There's a note saying the code was added to reduce a bug report regarding flicker...I just wonder if they threw the baby out with the bathwater on this one.

See [this answer](http://stackoverflow.com/a/2613272/719186). — LarsTech, Oct 15 '12 at 19:44
WM_PAINT is the Win32 Paint message... Surfaced as Control.Paint in WinForms. — Henk Holterman, Oct 15 '12 at 19:44
Using this in the constructor solved flickering in my case.: SetStyle(ControlStyles.DoubleBuffer | ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint, true); — aliassce, Oct 15 '12 at 20:34

score 1 · Answer 1 · answered Jun 02 '13 at 22:20

1

Try using DoubleBuffered = true;

answered Jun 02 '13 at 22:20

vbtheory

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Screen flicker issue

1 Answers1