PreviewDragStarted not firing for RadTreeView updating to Q3 2014

2 posts, 0 answers
  1. Jason Moore
    Jason Moore avatar
    22 posts
    Member since:
    Jun 2012

    Posted 20 Jan 2015 Link to this post


    I tried updating the Telerik DLL's  from file version 2013.3.1016.1050 to the newer DLLs from Q3 2014
    and noticed that the PreviewDragStarted is no longer firing for my RadTreeView.

    Any idea why?

  2. Milena
    Milena avatar
    226 posts

    Posted 22 Jan 2015 Link to this post

    Hello Jason,

    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: 

    telerik:TreeViewSettings.DragDropExecutionMode="Legacy" IsDragDropEnabled="True" >
    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.


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