HELP! Inventory click event cancellation?

So I've been coding a shop plugin, and for some reason, whenever I attempt to set the InventoryClickEvent cancellation when someone clicks on an item in the shop inventory, so they can't take the item out. I still can. Here's my command code:

Code:java

if(cmd.getName().equalsIgnoreCase("shop")){
p.openInventory(shopInventory);
shopInventory.clear();
shopInventory.addItem(new ItemStack(Material.ANVIL));
}

here's my event code:

Code:

@EventHandler
        public void onInventoryClick(InventoryClickEvent event) {
          if(event.getInventory().getName().equals("shopInventory")){
                if(event.getCurrentItem().getType() == (Material.ANVIL)){
                    event.setCancelled(true);
                    event.getWhoClicked().getInventory().addItem(new ItemStack(Material.APPLE));
                }
        }

 

Do you have register the event?

 

It's in the same class. Do I still have to register it even if it's in the same class?

 

Register the event. Your code is fine.

 

It worked! thank you so much