I have made a custom boom item and I would like to add default NBT data: the author the title and the pages.

 

This is my code: 

package com.scottbot.testmod.objects.items;

import com.scottbot.testmod.TestMod;
import com.scottbot.testmod.gui.ModBookReadScreen;
import net.minecraft.client.Minecraft;
import net.minecraft.client.util.ITooltipFlag;
import net.minecraft.entity.player.PlayerEntity;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.item.WrittenBookItem;
import net.minecraft.nbt.CompoundNBT;
import net.minecraft.nbt.ListNBT;
import net.minecraft.nbt.StringNBT;
import net.minecraft.util.ActionResult;
import net.minecraft.util.Hand;
import net.minecraft.util.StringUtils;
import net.minecraft.util.text.ITextComponent;
import net.minecraft.util.text.TextFormatting;
import net.minecraft.util.text.TranslationTextComponent;
import net.minecraft.world.World;

import javax.annotation.Nullable;
import java.util.List;

public class ModBookItem extends WrittenBookItem {

    public ModBookItem(Properties builder) {
        super(builder);

        ItemStack stack = new ItemStack(this);

        TestMod.LOGGER.info("tagging");
        addTags(stack);
    }

    public void addTags(ItemStack stack) {
        CompoundNBT nbt = stack.getOrCreateTag();
        TestMod.LOGGER.info(stack.getTag());

        ListNBT bookPages = new ListNBT();
        String[] values = {"test", "test2", "test3", "test4"};

        for (String text : values) { bookPages.add(StringNBT.valueOf("{\"text\":\"" + text + "}\""));}

        nbt.put("pages", bookPages);
        nbt.putString("author", "Test Author");
        nbt.putString("title", "Test Title");

        stack.setTag(nbt);

        TestMod.LOGGER.info(stack.hasTag());
        TestMod.LOGGER.info(stack.getTag());
    }

    @Override
    public void onCreated(ItemStack stack, World worldIn, PlayerEntity playerIn) {
        addTags(stack);
        super.onCreated(stack, worldIn, playerIn);
    }

    @Override
    public ActionResult<ItemStack> onItemRightClick(World worldIn, PlayerEntity playerIn, Hand handIn) {
        ItemStack stack = playerIn.getHeldItem(handIn);
        Minecraft.getInstance().displayGuiScreen(new ModBookReadScreen(new ModBookReadScreen.WrittenBookInfo(stack)));
        return ActionResult.resultSuccess(stack);
    }

    @Override
    public void addInformation(ItemStack stack, @Nullable World worldIn, List<ITextComponent> tooltip, ITooltipFlag flagIn) {
        TestMod.LOGGER.info(stack.getTag());
        TestMod.LOGGER.info(stack.hasTag());
        if (stack.hasTag()) {
            CompoundNBT compoundnbt = stack.getTag();
            TestMod.LOGGER.info(compoundnbt);
            assert compoundnbt != null;
            String s = compoundnbt.getString("author");
            TestMod.LOGGER.info(s);
            if (!StringUtils.isNullOrEmpty(s)) {
                tooltip.add((new TranslationTextComponent("book.byAuthor", s)).applyTextStyle(TextFormatting.GRAY));
            }
    }

}

 

When I start the game, it logs that the tags were added: 

Quote

{pages:['{"text":"test}"','{"text":"test2}"','{"text":"test3}"','{"text":"test4}"'],author:"Test Author",title:"Test Title"}

 

But when I actually get it from the creative menu it doesn't have the author tag and when I open the book it says invalid tag.

 

Any help would be appreciated, thanks!

 

 

Just a heads up, running your addTags method in the item constructor is pointless, unless you're doing it to test it.

Anyways, onCreated only fires when an item is crafted, which is why it's not working for you. You want to use fillItemGroup to change the stack in the creative tab.

How would I implement this?

 

I have this:

    @Override
    public void fillItemGroup(ItemGroup group, NonNullList<ItemStack> items) {
        if (this.isInGroup(group)) {
            ItemStack stack = new ItemStack(this);
            CompoundNBT nbt = stack.getOrCreateTag();
            TestMod.LOGGER.info(stack.getTag());

            ListNBT bookPages = new ListNBT();
            String[] values = {"test", "test2", "test3", "test4"};

            for (String text : values) { bookPages.add(StringNBT.valueOf("{\"text\":\"" + text + "}\""));}

            nbt.put("pages", bookPages);
            nbt.putString("author", "Test Author");
            nbt.putString("title", "Test Title");

            TestMod.LOGGER.info(stack.hasTag());
            TestMod.LOGGER.info(stack.getTag());
            TestMod.LOGGER.info(nbt);
            items.add(new ItemStack(this, 1, nbt));
        }
    }

 

But still doesn't work

 

Don't create a new ItemStack at the end, use the one you made before.

Thanks so much! And how would I make it get the tags from the /give command?

That's a bit tougher, I don't actually know the best way to do that myself.

One option would be to use inventoryTick; Check if the tags are present, and put them in if not.

I'm sure someone who understands the system better than me could come up with a solution that isn't so hacky.

46 minutes ago, ScottBot10 said:

Thanks so much! And how would I make it get the tags from the /give command?

The tags are stored automatically in the ItemStack you should be able to just call ItemStack::getOrCreateTag

Where would I call it from? Is there a method for it?