Im unsure if this is a bug or an oversight/lack of knowledge on my part.
a widget called MainWidget.
A widget (named widget 1) which is just a size box with an image inside. (500x500 for me but it doesnt seem to matter.)
drag and drop operation (named BPDragAndDrop)
in the drag and drop operation add two vars: widgetToDrag (type: user widget) and mouseOffset (vector 2d) make both expose on spawn and instance editable.
in widget 1 override “On mouse button down” and “on drag detected” and fill them in as the images below show.
Then in the main widget in the designer set its visibility to “visible” and go the graph and override “On drop”
duplicate the widget 1 and call it widget 2
in the main widget drag both widget 1 and widget 2 into the viewport
You will also need to add a player controller and spawn the main widget and set it to show mouse cursor.
you should be able to drag both widgets around the viewport. However if when you release the mouse button and the mouse cursor is over the widget you are NOT dragging, the widget you ARE dragging will disappear. This only happens with one of the two widgets, try both. It seems to be which ever widget you dragged into the main widget second that disappears, but have only reproduced this once so it could be random.
You can download my project here
(compressed 1.64Mb rar): Dropbox - Error