Moving & Swapping Items

Move Hotbar Slot
   From Index = A
   To Index   = B

HotbarComponent->MoveHotbarSlot(FromIndex, ToIndex);

// Take one item from inventory
FItemInstance InvItem = InventoryComponent->TakeItemAt(InventorySlotIndex, 1);

// Get current hotbar item
FItemInstance HotbarItem = HotbarComponent->GetItemAtIndex(HotbarSlotIndex);

// Assign inventory item to hotbar
HotbarComponent->AssignItemToSlot(InvItem, HotbarSlotIndex);

// Put old hotbar item back in inventory
if (!HotbarItem.IsEmpty())
{
    InventoryComponent->AddItemInstance(HotbarItem);
}