Adding Components to a Block Based Item

To make sure a Component specified in a prefab gets added to the block-item representing a block simply, add the @AddToBlockbasedItem annotation to the Component class:

@AddToBlockBasedItem
public class SpecialBlockComponent implements Component {
}

This makes it so that if you have a prefab like the following:

{
  "SpecialBlock": {}
}

The SpecialBlockComponent will be added to the block-item entity (held in the hand, inventory, hotbar, etc) as well as the block entity which exists in the world.

When to use @AddToBlockBasedItem

Components generally do not need to be applied to the block-item. The exception is when you are listening to item events, such as the one triggered when when the user tries to place a block.

For example, say you wanted people to be able to place flowers in a pot (in addition to on the ground). You would need a FlowerComponent to be applied to the block-item so you can detect when the user is trying to place a flower.