During the last year we did some improvements in the RadTreeView control. We refactored the built-in drag&drop logic. Currently the control supports two drag drop managers to handle the corresponding commands through the attached property telerik:TreeViewSettings.DragDropExecutionMode,
which allows users to switch between both managers. The New
setting corresponds to the DragDropManager
while the Legacy
setting turns on the obsolete RadDragAndDropManager.
With Q2 2014
we've changed the default value of the attached property to New. This means that by default the DragDropManager will be activated.
So, back to your question - if you need to use PreviewDragStarted event you can:
1. Set the to DragDropExecutionMode to Legacy:
So, there would be no need to change anything else in your project.
2. Use the new DragDropManager and OnDragInitialized
event. More about the DragDropManager events in RadTreeView you can see in our help topic Drag and Drop
Please excuse us for the inconvenience caused and let us know if you need any further assistance.
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.