Hello, so I'm trying to add additional tooltips to items. I have it so that when you press a character, it will do something to a item. I want to be able to see that the item has been modified. I am using RenderTooltipEvent.PostBackRound, but it just keeps crashing. Here is my code:

@SubscribeEvent
public static void onTooltipPreEvent(RenderTooltipEvent.PostBackground event) {
    ItemStack stack = event.getStack();
    NBTTagCompound nbt;
    if (stack.hasTagCompound()) {
        nbt = stack.getTagCompound();
    } else {
        nbt = new NBTTagCompound();
    }
    if (nbt.hasKey(ModifactionTable.NBT_LOCK)) {
        if (nbt.getBoolean(ModifactionTable.NBT_LOCK)) {
            event.getLines().add("Item Modified");
        }
    }
}

Edited October 8, 20195 yr by TesterTesting135
Solved

How to solve this problem？

1 hour ago, diesieben07 said:

编写自己的线程，发布代码和遇到的问题。

@SubscribeEvent
    public void event(RenderTooltipEvent.Pre event){
        Minecraft mc = Minecraft.getInstance();
        event.setCanceled(true);
        mc.getTextureManager().bindTexture(ITEMGUI);
        this.blit(event.getX(),event.getY(),0,0,109,158);
    }

Rendering problems, how should be solved?