Logic Contemplate

1. To drag and drop, we don't need to implement how to drag, because Apple has already implemented for us
2. To identify the thing we drop, we need to know the item's Uniform Type Identifier, for image, it is .image
3. To accept the thing we drop, we use the onDrop modifier

1. We act on the things we drop, we use a DropDelegate class

• The origin of the drop item is at the top left corner (not the center)