Hi Janesh,
You can hide the treeview control during loading of the form by setting the HideonLoad property of docking manager.
[C#]
this.dockingManager1.SetHiddenOnLoad(this.treeViewAdv1, true);
Please refer to the attached sample and let me know if you need more assistance with this incident.
http://websamples.syncfusion.com/samples/Tools.Windows/F61622/main.htmBest regards,
Poly