Custom food that applies a random effect.

[KiwiChris84]

Hey, I've been trying to make a custom food that gives the player a random potion effect when they consume it However, this hasn't exactly worked out for me the greatest, and I would like to know if I'm going about it all wrong or if there is something I can do with what I have to fix it. Here's my mod.

public class coolNewItem
{
    public static final String MOD_ID = "coolnewitem";
    // Directly reference a slf4j logger
    private static final Logger LOGGER = LogUtils.getLogger();


    public coolNewItem()
    {

        IEventBus eventBus = FMLJavaModLoadingContext.get().getModEventBus();

        ModItems.register(eventBus);

        eventBus.addListener(this::setup);

        // Register ourselves for server and other game events we are interested in
        MinecraftForge.EVENT_BUS.register(this);
    }

    private void setup(final FMLCommonSetupEvent event)
    {
        // some preinit code
        LOGGER.info("HELLO FROM PREINIT");
        LOGGER.info("DIRT BLOCK >> {}", Blocks.DIRT.getRegistryName());
    }

}

package net.kiwichris84.items;

import net.kiwichris84.coolnewitem.coolNewItem;
import net.minecraft.world.item.CreativeModeTab;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.Items;
import net.minecraftforge.eventbus.api.IEventBus;
import net.minecraftforge.registries.DeferredRegister;
import net.minecraftforge.registries.ForgeRegistries;
import net.minecraftforge.registries.RegistryObject;

public class ModItems extends Items {
    public static final DeferredRegister<Item> ITEMS =
            DeferredRegister.create(ForgeRegistries.ITEMS, coolNewItem.MOD_ID);

    public static final RegistryObject<Item> EYE_OF_ALWORTH = ITEMS.register("eye_of_alworth",
            ()-> new Item(new Item.Properties().tab(CreativeModeTab.TAB_MISC).food(ModFoods.EYE_OF_ALWORTH)));



    public static void register(IEventBus eventBus){
        ITEMS.register(eventBus);
    }

}

package net.kiwichris84.items;


import net.minecraft.world.food.FoodProperties;


public class ModFoods extends ModItems {
    public static final FoodProperties EYE_OF_ALWORTH = (new FoodProperties.Builder()).fast().nutrition(4).saturationMod(0.2F).alwaysEat().build();
            }

package net.kiwichris84.items;

import com.mojang.bridge.game.GameSession;
import net.kiwichris84.coolnewitem.coolNewItem;
import net.minecraft.client.Session;
import net.minecraft.world.effect.MobEffect;
import net.minecraft.world.effect.MobEffectInstance;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.Level;
import net.minecraftforge.event.TickEvent;
import net.minecraftforge.event.entity.living.LivingEntityUseItemEvent;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.LogicalSide;
import net.minecraftforge.fml.common.Mod;

import java.util.Objects;
@Mod.EventBusSubscriber(modid= coolNewItem.MOD_ID)
public class ModEventListeners {

    @SubscribeEvent
    protected static void onFoodEaten(LivingEntityUseItemEvent.Finish event) {
        if (event.getEntityLiving() instanceof Player) {
            Player player = (Player) event.getEntity();
            player.removeAllEffects();
            if (player.getMainHandItem().getItem().toString().equals("eye_of_alworth")){
                    int random = (int) ((Math.random() * 32) +1);
                    player.addEffect(new MobEffectInstance(Objects.requireNonNull(MobEffect.byId(random)), 1200, 2));}

            }

        }
    }

I know there is a lot of unused imports, I'll fix that later, but the problem's I've seen so far with the project is that it gives two potion effects instead of one, making me think it is firing twice. The wither effect simply doesn't work, the potion icons in the top right don't go away, and that the levitation effect lasts forever. I would assume that these things all stem from the same root issue, so if anyone could help me out I would appreciate it. 

Also, I know I'm not the best coder in the world, this is my first minecraft mod.

Thanks in advance to anyone willing to take the time to help a brother out.

[Luis_ST]

1. 53 minutes ago, KiwiChris84 said:

   player.getMainHandItem().getItem().toString().equals("eye_of_alworth")

   why did you check the Item name, you can just compare the Items with the == operator

2. why did you use LivingEntityUseItemEvent.Finish? you can just override #finishUsingItem in your Item class and perform the action you want there

3. 1 hour ago, KiwiChris84 said:

   int random = (int) ((Math.random() * 32) +1);

   i would recommend you to avoid constants when working with registries
   you can use something like:

   		List<MobEffect> effects = Lists.newArrayList(ForgeRegistries.MOB_EFFECTS.getValues());
   		MobEffect randomEffect = effects.get(new Random().nextInt(effects.size()));

[KiwiChris84]

And doing that should fix the effect triggering twice every time a food is eaten?

[Luis_ST]

yeah it should, this is the logic of the vanilla SuspiciousStewItem

[Luis_ST]

1 hour ago, diesieben07 said:

• Do not create a new Random instance every time.
• You might want to consider using Iterables.get instead of copying into a list every time.

i know, this was just a simple example how it could be possible to do

[KiwiChris84]

When I attempted to replace the the .equals toString part of my if statement i recieved this error

Operator '==' cannot be applied to 'net.minecraft.world.item.Item', 'net.minecraftforge.registries.RegistryObject<net.minecraft.world.item.Item>'

 

[Luis_ST]

you need to call RegistryObject#get

[KiwiChris84]

It says that registryobject#get is a static method. Also, when I tried to change to override the Item class extending the class said that there is no default constructor, and implementing the class said that an interface was required and to be honest I'm not familiar enough with setting up an interface class properly.

[KiwiChris84]

or my apologies, its a non static method that cannot be called from a static context. I should read things twice lol

[Luis_ST]

show how you call it

Edited May 27, 2022 by Luis_ST

[KiwiChris84]

here

    @SubscribeEvent
    protected void onFoodEaten(LivingEntityUseItemEvent.Finish event) {
        if (event.getEntityLiving() instanceof Player) {
            Player player = (Player) event.getEntity();
            player.removeAllEffects();
            if (player.getMainHandItem().getItem()== RegistryObject.get(EYE_OF_ALWORTH)){
                    int random = (int) ((Math.random() * 32) +1);
                    player.addEffect(new MobEffectInstance(Objects.requireNonNull(MobEffect.byId(random)), 1200, 2));}

            }

        }
    }

 

[Luis_ST]

you need to call

EYE_OF_ALWORTH.get()

 

Edited May 27, 2022 by Luis_ST

[KiwiChris84]

Alright that works, thank you, but for changing the code to finishUsingItem how would I go about that. I know how to override but It seems I cant extend Item or implement it 

[Luis_ST]

it's a class your Item class should be able to extends the Item class

Edited May 27, 2022 by Luis_ST

[KiwiChris84]

Attempting to do that gives me this though.

There is no default constructor available in 'net.minecraft.world.item.Item'

 

[Luis_ST]

did you add the constructor of the Item class (parameter Item.Properties),

your IDE should do this automatically for you

[KiwiChris84]

I guess not, how would I do that?

[Luis_ST]

use your IDE to add the super constructor,

all recommend IDE's have this feature (IntelliJ, Eclipse)

[KiwiChris84]

Alright I did that, and now for the  Player player declaration what should I do to fix the variables? now "event" is marked as red

public class ModEventListeners extends Item {

    public ModEventListeners(Properties pProperties) {
        super(pProperties);
    }
    
    @Override
    public ItemStack finishUsingItem(ItemStack pStack, Level pLevel, LivingEntity pLivingEntity) {
        Player player = (Player) event.getEntity();
        if (player.getMainHandItem().getItem()== EYE_OF_ALWORTH.get()){
            int random = (int) ((Math.random() * 32) +1);
            player.addEffect(new MobEffectInstance(Objects.requireNonNull(MobEffect.byId(random)), 1200, 2));}

        return this.isEdible() ? pLivingEntity.eat(pLevel, pStack) : pStack;

 

[Luis_ST]

you can check if the LivingEntity is an instance of Player, then you can cast it to a Player
or you use the java 14 instanceof pattern matching

[KiwiChris84]

package net.kiwichris84.items;


import net.kiwichris84.coolnewitem.coolNewItem;
import net.minecraft.world.effect.MobEffect;
import net.minecraft.world.effect.MobEffectInstance;
import net.minecraft.world.entity.LivingEntity;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.level.Level;
import net.minecraftforge.fml.common.Mod;
import org.jetbrains.annotations.NotNull;
import java.util.Objects;
@Mod.EventBusSubscriber(modid= coolNewItem.MOD_ID)
public class ModEventListeners extends Item { public ModEventListeners(Properties pProperties) {super(pProperties);}
    @Override
    public @NotNull ItemStack finishUsingItem(@NotNull ItemStack pStack, @NotNull Level pLevel, @NotNull LivingEntity pLivingEntity) {
        if (pLivingEntity instanceof Player) {
            Player player = (Player) pLivingEntity;
            if (player.getMainHandItem().getItem() == ModItems.EYE_OF_ALWORTH.get()) {
                int random = (int) ((Math.random() * 32) + 1);
                player.addEffect(new MobEffectInstance(Objects.requireNonNull(MobEffect.byId(random)), 1200, 2));
                return this.isEdible() ? pLivingEntity.eat(pLevel, pStack) : pStack;
            }
        }
        return this.isEdible() ? pLivingEntity.eat(pLevel, pStack) : pStack;
    }
}

It doesn't seem to be firing now, what should I do?

[KiwiChris84]

package net.kiwichris84.items;


import net.minecraft.world.food.FoodProperties;


public class ModFoods extends ModItems {
    public static final FoodProperties EYE_OF_ALWORTH = (new FoodProperties.Builder()).fast().nutrition(4).saturationMod(0.2F).alwaysEat().build();
            }

package net.kiwichris84.coolnewitem;

import com.mojang.logging.LogUtils;
import net.kiwichris84.items.ModItems;

import net.minecraft.world.level.block.Blocks;
import net.minecraftforge.common.MinecraftForge;

import net.minecraftforge.eventbus.api.IEventBus;
import net.minecraftforge.fml.common.Mod;
import net.minecraftforge.fml.event.lifecycle.FMLCommonSetupEvent;

import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
import org.slf4j.Logger;



// The value here should match an entry in the META-INF/mods.toml file
@Mod(coolNewItem.MOD_ID)
public class coolNewItem
{
    public static final String MOD_ID = "coolnewitem";
    // Directly reference a slf4j logger
    private static final Logger LOGGER = LogUtils.getLogger();


    public coolNewItem()
    {

        IEventBus eventBus = FMLJavaModLoadingContext.get().getModEventBus();

        ModItems.register(eventBus);

        eventBus.addListener(this::setup);

        // Register ourselves for server and other game events we are interested in
        MinecraftForge.EVENT_BUS.register(this);
    }

    private void setup(final FMLCommonSetupEvent event)
    {
        // some preinit code
        LOGGER.info("HELLO FROM PREINIT");
        LOGGER.info("DIRT BLOCK >> {}", Blocks.DIRT.getRegistryName());
    }

}

package net.kiwichris84.items;

import net.kiwichris84.coolnewitem.coolNewItem;
import net.minecraft.world.item.CreativeModeTab;
import net.minecraft.world.item.Item;
import net.minecraft.world.item.Items;
import net.minecraftforge.eventbus.api.IEventBus;
import net.minecraftforge.registries.DeferredRegister;
import net.minecraftforge.registries.ForgeRegistries;
import net.minecraftforge.registries.RegistryObject;

public class ModItems extends Items {
    public static final DeferredRegister<Item> ITEMS =
            DeferredRegister.create(ForgeRegistries.ITEMS, coolNewItem.MOD_ID);

    public static final RegistryObject<Item> EYE_OF_ALWORTH = ITEMS.register("eye_of_alworth",
            ()-> new Item(new Item.Properties().tab(CreativeModeTab.TAB_MISC).food(ModFoods.EYE_OF_ALWORTH)));



    public static void register(IEventBus eventBus){
        ITEMS.register(eventBus);
    }

}

These are my other classes for the mod.

[Luis_ST]

17 minutes ago, KiwiChris84 said:

    public static final RegistryObject<Item> EYE_OF_ALWORTH = ITEMS.register("eye_of_alworth",
            ()-> new Item(new Item.Properties().tab(CreativeModeTab.TAB_MISC).food(ModFoods.EYE_OF_ALWORTH)));

you did not use your Item class in when creating your Item,

also why did you use your ModEventListeners as Item class?

[KiwiChris84]

I was using that class while I was trying to create an event. So what should I do, move the methods to the ModItems?

[Luis_ST]

the class does not change the result, but i would recommend you to create a new class for the Item

a thing you need to do is create a new instance of the class inside the RegistryObject instead of using the Item class