Hi Sergey,

The native behavior of the dblclick on a node in a treeview control is to expand or collapse the node. Unlike a VFP control, this OLE control appears to execute it native behavior before, not after, the DblClick() method fires. Therefore, by the time any code in the DblClick() method is reached, the expand or collapse has already occurred.

I can easily reverse this by issuing a

this.Expanded = !( this.Expanded )

in the DblClick() method. The effect is a flicker visible to the user as the previous unwanted expand or collapse is reversed.

I am tying to prevent the flicker by preventing the expand/collapse from occuring in the first instance.

Another approach would be to lock the control from repainting using the LockUpdate API function. The problem again is that the unwanted native behavior has already occurred before the LockUpdate code is reached in the DblClick() method, so issuing a LockUpdate call in DblClick() is ineffective.

Thank you for your response. I hope you have an idea or two to share.

Regards,