If I understand your scenario correctly, you want to place a RadDock on the last position of the RadDockZone, when the user clicks on the docks title bar. Since this click starts dragging, the RadDock will always be placed on the same position instead at the end of the RadDockZone.
You can achieve the desired behavior by handling the client events OnClientDragStart
in order to check if the dock is moved by comparing the index and the RadDockZoneID of the dragged RadDock before and after it is moved. If they are equal, which means that the dock control's titlebar was only clicked, you can use the RadDockZone's client method dock(RadDock, index)
in order to move the clicked dock control to the last position of the zone.
I have attached a sample page, demonstrating the described behavior. You can use it as a reference for incorporating the desired feature into your actual project.
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