Moving control waits for it to be painted and that is slow

[Mark Nijhof]

Hello,

I made a small app that has those nice moving panels like Visual Studio has.
Now all goes fine until I open one of them that has a lot of child controls
in it. Actually it has one tabcontrol with two tabs, first tab without child
controls the second with (20+) child controls. Now opening and closing it
with the first tab visible goes fine, but when selecting the second tab the
opening shoks. It moves the panel 30 pixels and than it paints it witch
takes to long and than moves the next step. Closing however is no problem.
Also I have an other panel with almost the same child controls but without
the tabcontrol and that one acts fine too.

I have been looking into:
SetStyle(ControlStyles.UserPaint, true);

SetStyle(ControlStyles.AllPaintingInWmPaint, true);

SetStyle(ControlStyles.DoubleBuffer, true);

But this does not help a bit. I placed this in the contructor of the form
and also tried in the panel control.

Any help is appreciated.

-Mark