I am trying to add strength to the player on use, along with playing a sound.

here's the code:

public class DarksteelHornItem extends Item {
    public DarksteelHornItem(Properties properties) {
        super(properties);
    }

    @Override
    public InteractionResultHolder<ItemStack> use(Level level, Player player, InteractionHand hand) {
        if(level.isClientSide() && hand == InteractionHand.MAIN_HAND) {
            level.playSound(player, player.getX(), player.getY(), player.getZ(), SoundEvents.RAID_HORN, SoundSource.PLAYERS, 1.0F, 1.0F);
            player.addEffect(new MobEffectInstance(new MobEffect(), 5));

        }
        return super.use(level, player, hand);
    }
}

Edited July 17, 20232 yr by Choccy Biscuit
formatting

addEffect should be run on server-side (level.isClientSide==false). playSound on client-side (isClientSIde==true).

1 hour ago, MFMods said:

addEffect should be run on server-side (level.isClientSide==false). playSound on client-side (isClientSIde==true).

I've changed it to this, but I get the error "'MobEffect(net.minecraft.world.effect.MobEffectCategory, int)' has protected access in 'net.minecraft.world.effect.MobEffect'"

It also returns the error on run:

"required: MobEffectCategory,int
  found:    no arguments
  reason: actual and formal argument lists differ in length"

public class DarksteelHornItem extends Item {
    public DarksteelHornItem(Properties properties) {
        super(properties);
    }

    @Override
    public InteractionResultHolder<ItemStack> use(Level level, Player player, InteractionHand hand) {
        if(level.isClientSide() == true && hand == InteractionHand.MAIN_HAND) {
            level.playSound(player, player.getX(), player.getY(), player.getZ(), SoundEvents.RAID_HORN,           SoundSource.PLAYERS, 1.0F, 1.0F);
        if(level.isClientSide() == false && hand == InteractionHand.MAIN_HAND){
            player.addEffect(new MobEffectInstance(new MobEffect(),5));
            }
        player.getCooldowns().addCooldown(this,400);
        }
        return super.use(level, player, hand);
    }
}

Edited July 17, 20232 yr by Choccy Biscuit
detail

nevermind, fixed