Hello,

 

I have an item that, when right clicked, opens a gui with a text field in it. When a button on the gui is pressed, it should update the NBT of the ItemStack associated with it.

 

However, this isn't a conventional gui. When you open this gui, you can have this gui running in the "background" and do other things in Minecraft. This means that it should be possible to drop the item that opens the gui or place it in some chest, modify the text field of that gui, and update the NBT of that ItemStack, even if it is no longer in the player's inventory.

 

I'm a bit stuck on getting the reference to the ItemStack though. I have

  @Override
  public IMessage onMessage(MyMessage message, MessageContext ctx) {
    if (ctx.side.isServer()) {
      System.out.print("[DEBUG] MyMessage received on server!");
      // Somehow get the ItemStack on the server side that corresponds to this packet
      // This would be easy if it's always the player's held item, but it's not
    }
    
    return null;
  }

 

Is something like this possible?

When the GUI first opens you should be able to get the reference from the player's held item (that is what opened the GUI...) and save that reference.

 

That said, good fucking luck making sure what you just described works.