I am trying to to assign a placeholder at a predefined location on the canvas (everything else is a blur background where nothing exists). Once the user drags the first node onto the location where the placeholder is, I want to remove the background blur. After this the operation is as usual. Users can drag mode nodes to the canvas and link them.
You’ll notice we keep track of model changes, and when they are completed transactions, we determine whether we should or shouldn’t be in “edit mode.” The rest of the setup is just straightforward setting of properties like mouseDragOver and mouseDrop.