So I'm trying to make a very small mod to ban the use of specific items.  The mod just constantly checks each player's inventory and sets any slot with a "restricted" item to null.

 

This works fine when it's loaded on both the client and the server; the moment I move an item from the Creative Inventory to my hotbar, it disappears.  But I really want this mod to be server-side only.  Here's my code:

 

@SubscribeEvent
    public void onPlayerTick(PlayerTickEvent e) {
        EntityPlayer player = e.player;
        if (!e.player.worldObj.isRemote) {
            for (int i = 0; i < player.inventory.mainInventory.length; i++) {
                ItemStack is = player.inventory.mainInventory[i];
                if (is != null) {
                    Item it = is.getItem();
                    // MFYLog.bannedItems is an ArrayList<Item>
                    for (Item compare : MFYLog.bannedItems) {
                        if (it == compare) {
                            player.inventory.setInventorySlotContents(i, null);
} } } } }

 

The Bug: The item isn't usable, which is good, but it is visible.  It sticks around on the hotbar, and can be moved around my inventory.  The item will disappear if I interact with any other block in the game.

 

Reading other posts, my best guess is I need to send a packet of some type, but I don't have much experience with packets, and the tutorials I could find only talked about custom packets.  In this case I just want to send whatever vanilla packet is normally sent with an inventory update.  Any hints?

Awesome, that did the trick.  The Immutable Set and event.phase tips are also great to know.  Thanks!