Can't get Drag-drop dragging action?

[newbiemate]

If you think back to diablo 3, if you drag a sword from the inventory screen, it'll highlight slots where you can drop the item into to equip the sword on your character. This visually prevents the player from dropping the item onto the character's foot, because the character's foot cannot equip a sword. Only their hands can, so that's why the slots on their hands are highlighted.

This is a nice UX, and I'm trying to build the same thing using renpy. I've been playing with Drag and Drop (https://www.renpy.org/doc/html/drag_drop.html), and the drag-drop mechanism works pretty well. However, the issue is I don't know how to 'highlight' the slots while the displayable is being dragged.

In this test snippet:

Code: Select all

init python:
    def do_dragged(drags, drop):
        if not drop:
            return
        return True

screen slot_idle():
    add "images/slot_idle.png" xpos 100 ypos 100
    
screen slot_highlight():
    add "images/slot_highlight.png" xpos 100 ypos 100

screen begin():
    draggroup:
        drag:
            drag_name "sword"
            child "images/sword.png"
            droppable True
            dragged do_dragged
            xpos 500
            ypos 500

label start:
    show screen slot_idle()
    call screen begin()
    return

The function do_dragged() seems to only run when the displayable is dropped, not while it's being dragged. How can I hide the slot_idle screen and show the slot_hightlight screen while I am dragging the displayable? And then vice-versa when the displayable has been dropped (ie, change back to idle instead of highlight)?