Get dragged item

[annet]

Hi all,

I am using a RadTreeList with drag and drop enabled. This works fine.
Now I want to prevent items at the highest level from being dropped on another item. These items cannot be the child of another item.

How can I accomplish this?

I think I can prevent the dropping of certain items in the itemDragging, but I don't know how to access the dragged_item here.
Then I can do something like:
if (level of the dragged item  is zero) then args.set_canDrop(false);

Annet

[sitefinitysteve]

What if you do it on the server side in OnItemDrop and just check if the item draggings parent is null...if it is just set cancelled to true?

http://www.telerik.com/help/aspnet-ajax/treelist-items-drag-drop.html

Steve

[annet]

Thank you Steve, this prevents the actual dropping of the item, which I also needed to do.
But during dragging, I would like to give the user a visible clue when an item can't be dropped.
I use the client-side itemDragging for that, like in the Telerik demo.
Can this be done?

Annet

[sitefinitysteve]

Well setting cancel prevents the item being dropped if the condition is met, setting it globally clearly isn't the way to go :)

So this is something I did recently

public void OnWorkflowList_ItemDrop(object sender, TreeListItemDragDropEventArgs e) {
    var item = e.DraggedItems.First();
    var dataItem = item.DataItem as Approval;

    var approvalID = item.GetDataKeyValue("ApprovalID");
    var parentApprovalID = item.GetDataKeyValue("ParentApprovalID");

    Approval approval = base.RTOContext.Approvals.Get(new Guid(approvalID.ToString()));
    Approval parentApproval = null;
    if (parentApprovalID != null) {
        parentApproval = base.RTOContext.Approvals.Get(new Guid(parentApprovalID.ToString()));
    }

    //We're dragging to the header
    if (e.DestinationDataItem == null) {
        if ((approval.PickTypeID != (byte)WorkflowItemsTypeEnum.Assigned || approval.PickTypeID != (byte)WorkflowItemsTypeEnum.Assigned) && approval.ApproverID == null) {
            //Not possible to drag an unknown approver item to the root with nobody to pick it
            e.Canceled = true;
            commandMessageLiteral.Text = "Invalid Re-order, item has no defined approver, so nobody will be able to pick them (cats and dogs living together, mass hysteria)";
        }
    }
    else {
        //Check to see if the item we're dropping it on is approved, and this person doesn't have an approver assigned
        if (approval.ApproverID == null && (parentApproval.StatusType != StatusType.Pending || parentApproval.StatusType != StatusType.NotRequired || parentApproval.StatusType != StatusType.Empty)) {
            e.Canceled = true;
            commandMessageLiteral.Text = "Invalid Re-order, the item you're dropping it onto isn't pending, so nobody will be able to pick this person";
        }
    }

}

So this is the line that checks to see if it's being dragged into the header, and that's where you'd cancel with a message

//We're dragging to the header
    if (e.DestinationDataItem == null) {

NOW, clientside though it looks like it might be easy as well
Handle OnItemDropping

function onItemDropping(sender, args){
  var dataItem = args.get_targetDataItem();

  if(dataItem.get_isRoot()){
     args.set_cancel(true); //I believe this is how to cancel
  }

}

Now this is me just looking at the documentation and winging it, so I'm not entirely sure if that will work, but seems okay

[annet]

Thanks for your input. I can't get it to work client-side, so I settled for the server-side solution.

Annet