How to swap items in inventory with 1 widget

Hi everyone I know I only just posted a question yesterday but this one is different in the way that it is about the Inventory of the game I’m creating. anyway I am trying to make drag and drop work but don’t know how I can do it with a single widget as my inventory is 1 widget (I don’t have any separate widgets in relation to the inventory such as slots etc.) so I was wondering if someone could help me with how I could achieve this thanks in advance