What UMG button am i dragging?

i am trying to drag a button (inside my UMG) and drop to another button.
The button where i drop should become with the image of the dragged button.
Actually when i drag my button, i can see the image of the first button in my array element because my ButtonPressed variable is not setted yet.
I would like to know how can i determinate which button i am draggin for set my variable (in the image called ButtonPressed).