Hi. 

 

In my mod I have spells on a staff. Classes Staff and Spell are both items. To select the next spell on the staff, I am modifying the tag on the staff's stack on a key press in the client thread:

 

	@SideOnly(Side.CLIENT)
@SubscribeEvent
public void onKeyInput(KeyInputEvent event) {
	if (keyBindings.get("nextSpell").isPressed()) {
		EntityPlayerSP p = Minecraft.getMinecraft().thePlayer;
		ItemStack stack = p.getCurrentEquippedItem();
		if (stack != null) {
			Item i = stack.getItem();
			if (i instanceof Staff) {
				((Staff) i).nextSpell(stack);
			}
		}
	}
        }

 

Staff.nextSpell() modifies the tag on the stack, setting the index to the current spell. Later when I use the spell, I want to run on the server thread because it is going to modify the world:

 

	@Override
public boolean onItemUse(ItemStack stack, EntityPlayer playerIn, World world, 
		BlockPos pos, EnumFacing side, float hitX, float hitY, float hitZ) {

	System.out.println("tag="+stack.getTagCompound());
	//Only on server side.
	if (world.isRemote) {
		return true;
	}

 

The println shows that index has been updated only the tag in the client thread:

 

[14:31:09] [Client thread/INFO] [sTDOUT]: [ds.plato.item.spell.Spell:onItemUse:97]: tag={3:"SpellLine",2:"SpellCone",index:6,1:"SpellCircle",0:"SpellBox",7:"SpellSeaShell",6:"SpellRectangle",5:"SpellPyramid",4:"SpellMeasure",8:"SpellSphere",}
[14:31:09] [server thread/INFO] [sTDOUT]: [ds.plato.item.spell.Spell:onItemUse:97]: tag={3:"SpellLine",2:"SpellCone",index:0,1:"SpellCircle",0:"SpellBox",7:"SpellSeaShell",6:"SpellRectangle",5:"SpellPyramid",4:"SpellMeasure",8:"SpellSphere",}

 

How can I set the stack in the server thread so that it is in sync with the client thread?

 

You need packets.

Funny, this code was running on 1.7 with no messaging. Not sure how (probably badly). Anyway, works fine now with messaging. Thanks Draco.