I tried this code but I got an error while making custom spawn egg for a skeleton(this skeleton is a vanilla minecraft entity) I think I know why this error is coming, but I don't know how to solve it, can you please help, I am sharing the code - 

package com.anirudh.forgemod.init;

import com.anirudh.forgemod.ForgeMod;
import com.anirudh.forgemod.items.ItemBase;
import com.anirudh.forgemod.items.ModSpawnEggItem;
import com.anirudh.forgemod.items.StrongestApple;
import com.anirudh.forgemod.util.enums.ModArmorMaterial;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.EquipmentSlot;
import net.minecraft.world.item.ArmorItem;
import net.minecraft.world.item.CreativeModeTab;
import net.minecraft.world.item.Item;
import net.minecraftforge.fmllegacy.RegistryObject;
import net.minecraftforge.registries.DeferredRegister;
import net.minecraftforge.registries.ForgeRegistries;

public class ModItems {

    public static DeferredRegister<Item> ITEMS = DeferredRegister.create(ForgeRegistries.ITEMS, ForgeMod.MOD_ID);

    //Items
    public static final RegistryObject<Item> RUBY = ITEMS.register("ruby", ItemBase::new);
    public static final RegistryObject<StrongestApple> POISON_APPLE = ITEMS.register("strongest_apple", StrongestApple::new);

    public static final RegistryObject<ModSpawnEggItem> SKELETON_SPAWN_EGG = ITEMS.register("skeleton_spawn_egg",
            () -> new ModSpawnEggItem(EntityType.SKELETON, 0x00FFA8, 0x326D59, new Item.Properties().tab(CreativeModeTab.TAB_MATERIALS)));

    //Armor
    public static final RegistryObject<ArmorItem> RUBY_HELMET = ITEMS.register("ruby_helmet", () ->
            new ArmorItem(ModArmorMaterial.RUBY, EquipmentSlot.HEAD, new Item.Properties().tab(CreativeModeTab.TAB_COMBAT)));

    public static final RegistryObject<ArmorItem> RUBY_CHESTPLATE = ITEMS.register("ruby_chestplate", () ->
            new ArmorItem(ModArmorMaterial.RUBY, EquipmentSlot.CHEST, new Item.Properties().tab(CreativeModeTab.TAB_COMBAT)));

    public static final RegistryObject<ArmorItem> RUBY_LEGGINGS = ITEMS.register("ruby_leggings", () ->
            new ArmorItem(ModArmorMaterial.RUBY, EquipmentSlot.LEGS, new Item.Properties().tab(CreativeModeTab.TAB_COMBAT)));

    public static final RegistryObject<ArmorItem> RUBY_BOOTS = ITEMS.register("ruby_boots", () ->
            new ArmorItem(ModArmorMaterial.RUBY, EquipmentSlot.FEET, new Item.Properties().tab(CreativeModeTab.TAB_COMBAT)));
}

 

First off, what's the error?
Second, can you show your ModSpawnEggItem class? 
And third, is that class really needed? Forge provides a spawn egg class, you don't need a custom one unless you want additional behavior.

I think the error comes from this java class even though it dosen't show any error - 

package com.mahidhoni123.forgemod.items;

import net.minecraft.core.BlockSource;
import net.minecraft.core.Direction;
import net.minecraft.core.dispenser.DefaultDispenseItemBehavior;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.MobSpawnType;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.SpawnEggItem;
import net.minecraft.world.level.block.DispenserBlock;
import net.minecraftforge.common.util.Lazy;
import net.minecraftforge.fml.util.ObfuscationReflectionHelper;
import net.minecraftforge.fmllegacy.RegistryObject;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;


public class ModSpawnEggItem extends SpawnEggItem {

    protected static final List<ModSpawnEggItem> UNADDED_EGGS = new ArrayList<>();
    private final Lazy<? extends EntityType<?>> entityTypeSupplier;

    public ModSpawnEggItem(final RegistryObject<? extends EntityType<?>> entityTypeSupplier, int p_43208_, int p_43209_, Properties p_43210_) {
        super(null, p_43208_, p_43209_, p_43210_);
        this.entityTypeSupplier = Lazy.of(entityTypeSupplier::get);
        UNADDED_EGGS.add(this);
    }

    public static void initSpawnEggs(){
        final Map<EntityType<?>, SpawnEggItem> EGGS = ObfuscationReflectionHelper.getPrivateValue(SpawnEggItem.class, null, "field_195987_b");
        DefaultDispenseItemBehavior dispenseBehavior = new DefaultDispenseItemBehavior() {

            @Override
            protected ItemStack execute(BlockSource p_123385_, ItemStack p_123386_) {
                Direction direction = p_123385_ .getBlockState().getValue(DispenserBlock.FACING);
                EntityType<?> type = ((SpawnEggItem) p_123386_.getItem()).getType(p_123386_.getTag());
                type.spawn(p_123385_.getLevel(), p_123386_, null, p_123385_.getPos(),
                        MobSpawnType.DISPENSER, direction != Direction.UP, false);
                    p_123386_.shrink(1);
                    return p_123386_;
            }
        };

        for (final SpawnEggItem spawnEgg : UNADDED_EGGS) {
            EGGS.put(spawnEgg.getType(null ), spawnEgg);
            DispenserBlock.registerBehavior(spawnEgg, dispenseBehavior);
        }
        UNADDED_EGGS.clear();
    }

    @Override
    public EntityType<?> getType(CompoundTag nbt) {
        return this.entityTypeSupplier.get();
    }
}

 

12 minutes ago, mahidhoni123 said:

I think the error comes from this java class even though it dosen't show any error

What's then the problem?

As uSkizzik already mentioned Forge has their own SpawnEggItem use it

Error =

Required RegistryObject<?extends EntityType<?>>

Provided EntityType<SKELETON>

but how do you access this class? The forge provided spawn egg

I typed ForgeSpawnEggItem.fromEntityType(EntityType.SKELETON) but now I saw a complimation error - 

Required Registry Object extends<? net.minecraft.entity.EntityType

Provided SpawnEggItem

Please check this link, hopefully you can check it out - https://docs.google.com/presentation/d/e/2PACX-1vQ3x-VnSHEmme9bIfJ26CeSuQHWZE8Atl4dRQvp9xtAItt5ucIZc6E8p8Edn1DMws35tJn6D4oR6x5p/pub?start=true&loop=false&delayms=3000

Please can you HELP instead of posting learn java learn java, PLEASE

you need to create a new ForgeSpawnEggItem and not a SpawnEggItem!

1 hour ago, mahidhoni123 said:

I typed ForgeSpawnEggItem.fromEntityType(EntityType.SKELETON) but now I saw a complimation error - 

Required Registry Object extends<? net.minecraft.entity.EntityType

Provided SpawnEggItem

Luis_ST Can you please show me an example I am trying to create a ForgeSpawnEggItem in my ModSpawnEgg class, but it keeps on saying the same error as shown above 

show the complete RegistryObject, you tried to create

Edited December 3, 20213 yr by Luis_ST

For now I have set it to null, but you can help - 

public static final RegistryObject<ModSpawnEggItem> SKELETON_SPAWN_EGG = ITEMS.register("skeleton_spawn_egg",
            () -> new ModSpawnEggItem(null , 0x00FFA8, 0x326D59, new Item.Properties().tab(CreativeModeTab.TAB_MATERIALS)));

 

Something like this - 

 public static final RegistryObject<ForgeSpawnEggItem> SKELETON_SPAWN_EGG = ITEMS.register("skeleton_spawn_egg",
            () -> new ForgeSpawnEggItem(null , 0x00FFA8, 0x326D59, new Item.Properties().tab(CreativeModeTab.TAB_MATERIALS)));

So what should I replace null with?

7 hours ago, mahidhoni123 said:

EntityType.SKELETON

a Supplier with the EntityType you want to spawn with it

Does this work?

    public static final RegistryObject<ForgeSpawnEggItem> SKELETON_SPAWN_EGG = ITEMS.register("skeleton_spawn_egg",
            () -> new ForgeSpawnEggItem(new Supplier<EntityType<? extends Mob>>() {
                @Override
                public EntityType<? extends Mob> get() {
                    return EntityType.SKELETON;
                }
            }, 0x00FFA8, 0x326D59, new Item.Properties().tab(CreativeModeTab.TAB_MATERIALS)));