TreeView Flickering Problem

This will cure your flicker, not the most elegant solution, but it works nicely. You will have to change your TreeView instance to use the derived class bellow. The code should be self explanatory if you take a look at WM_ERASEBKGND in MSDN.

internal class FlickerFreeTreeView : TreeView
{
public FlickerFreeTreeView()
: base()
{
}

private const int WM_ERASEBKGND = 0x0014;
protected override void WndProc(ref Message m)
{
if (m.Msg == WM_ERASEBKGND)
{
m.Result = IntPtr.Zero;
return;
}
base.WndProc(ref m);
}
}

Yes,

Put it into its own .cs file, and in your form make sure to qualify the control class name with the namespace, both on the declaration and when it is initialized. No troubles here.

Regards

[QUOTE]Originally posted by nvannote
This will cure your flicker [...]

I am also very grateful for your code. Although in my case it
did not remove the flicker completely, the improvement is
unexpectedly good.

I say unexpectedly because I tried other tricks - like
Invalidate/Update - and got no effect.

I am going to try it to list views ;)

Petru

Hi all,

Finally I have - thanks to Giovanni Montrone - a solution that
works satisfactory. There is a demo project that you can download
from:

http://www.codeproject.com/useritems/ListViewFF.asp?df=100&forumid=14314&select=422123
which solves precisely this problem. It seems, though, that indeed
the pair Invalidate/Update does not have the desired effect, so
one must use the WndProc approach.

In addition to the code in the second message of this
thread, a Validate for the big rectangle of the parent control
(ListView/TreeView) is required. With this adjustment, for me
the list view handled items refresh without any flicker.

The flicker-free tree view is easy to build using the patern
from the flicker-free list view.

Have fun!
Petru