Hide custom Submit button until all drops are occupied on drag n drop questions

I had a similar challenge in the past when the Custom Submit button was always visible. I had not considered that users would immediately click on the submit button without doing any interaction. :)

Here is what I did and I hope it makes sense.

I creates a custom Submit button, and for speed I created a shape rectangle the same color as the background behind the Submit button so that it basically covered and hid the Submit button. I named the colored rectangle shape "SubmitHideShape"

Each of the draggable elements had 3 states:

Normal

Dragged Over

Drop correct

When the user dragged an item onto the target item I created a trigger to change the drag item to Dragged Over. (The trigger had to allow for the user dragging over any of the drop targets)

When all of the items were dragged over, I created a trigger that basically said

When each of the draggable items were in a state of Dragged Over, hide the SubmitHideShape...which showed the Submit Button.

I could have simply hidden the submit button when the slide started and then set the Submit button to normal when all of the draggable items were set to Dragged Over...but I wanted to make my life hard :) and at the time it was a fast solution to get it done....