I am having Problems using a custom MobEffect in my Item Registry. 

public static final RegistryObject<Item> MAGNETIC_SCROLL =
            ITEMS.register("magnetic_scroll",
                    () -> new BuffSpellItem(MobEffectRegistry.MAGNETIC_MOB_EFFECT.get(), 5000, 0, 10, 10));

for some reason I get a null Point Exception although the Mob Effect itself without the Item to use it works fine.

Here is the Mob Effect Registry:

public class MobEffectRegistry {

    public static final DeferredRegister<MobEffect> MOB_EFFECT = DeferredRegister.create(ForgeRegistries.MOB_EFFECTS, MiltenMagic.MOD_ID);

    public static final RegistryObject<MobEffect> MAGNETIC_MOB_EFFECT = MOB_EFFECT.register("magnetic", MagneticMobEffect::new);
}

do I need to register my Objects in a specific order?

Basic objects like Blocks and Items are always registered first. This is to avoid circular references in the loading/registration.

You should change your item constructor to accept a Supplier<MobEffect> or RegistryObject<MobEffect> as the parameter and then use the get() when you need the real object later at runtime. 

that is good to know, it works when I use a Supplier thanks

Is there a way to get a supplier from vanilla MobEffects? because I use the same class with an vanilla mob effect aswell. or should I just write two classes, one for my custom mob effects and one for vanilla mob effects?

Use a lambda expression and create a new Supplier, for the vanilla MobEffects.

Sometimes the easy answer is the right one thank you good sir

13 minutes ago, Luis_ST said:

Use a lambda expression and create a new Supplier, for the vanilla MobEffects.

 

hey, a bit late to the forum. im new to mc modding and i dont really know what a supplier is, would be grateful if you shared a bit of info.