Block Interaction

There are many different ways players (and other things) can interact with blocks, such as right clicking, left clicking, colliding, walking on, and of course mining.

This page will cover the basics of the most common types of interaction with blocks.

Player Right Click

Since left clicking, or “punching”, a block does not generally result in any unique behavior, it is probably fair to say right clicking, or “activation”, is the most common method of interaction. And thankfully, it is also one of the simplest to handle.

`use`

public ActionResultType use(BlockState state, World worldIn, BlockPos pos, PlayerEntity player, Hand handIn, BlockRayTraceResult hit)

This is the method that controls right click behavior.

Parameters

Type	Name	Description
`BlockState`	`state`	The state of the block that was clicked
`World`	`worldIn`	The world that the block was clicked in
`BlockPos`	`pos`	The position of the block that was clicked
`PlayerEntity`	`player`	The player who did the clicking
`Hand`	`handIn`	The hand with which the player clicked
`BlockRayTraceResult`	`hit`	Where on the block’s bounds it was hit

Return Value

ActionResultType is the result right clicking, see example usages below. ActionResultType#SUCCESS means the right click action was successful. ActionResultType#CONSUME means that the right click action was consumed. ActionResultType#PASS is the default behavior, for when the block has no right click behavior, and allows something else to handle the right click. ActionResultType#FAIL means that the action failed.

Enum Value	Example Usage
`SUCCESS`	Eating a slice of cake.
`CONSUME`	Tuning a noteblock.
`PASS`	When right-clicking dirt. Or any other basic block.
`FAIL`	When attempting to place a minecart on a block other than rails.

Important

Returning ActionResultType#CONSUME from this method on the client will prevent it being called on the server. It is common practice to just check worldIn#isClientSide and return ActionResultType#SUCCESS, and otherwise go on to normal activation logic. Vanilla has many examples of this, such as the chest.

Usage examples

The uses for activation are literally endless. However, there are some common ones which deserve their own section.

GUIs

One of the most common things to do on block activation is opening a GUI. Many blocks in vanilla behave this way, such as chests, hoppers, furnaces, and many more.

Activation

Another common use for activation is, well, activation. This can be something like “turning on” a block, or triggering it to perform some action. For instance, a block could light up when activated. A vanilla example would be buttons or levers.

Important

use is called on both the client and the server, so be sure to keep the sidedness of your code in mind. Many things, like opening GUIs and modifying the world, should only be done on the server-side.

Block Placement

`setPlacedBy`

public void setPlacedBy(World worldIn, BlockPos pos, BlockState state, @Nullable LivingEntity placer, ItemStack stack)

Called by BlockItems after a block is set in the world, to allow post-place logic.

Parameters:

Type	Name	Description
`World`	`worldIn`	The world that the block was placed in
`BlockPos`	`pos`	The position where the block was placed
`BlockState`	`state`	The state of the block that was placed
`LivingEntity`	`placer`	The entity who placed the block
`ItemStack`	`stack`	The item block that was placed

Player Break/Destroy

`attack`

public void attack(BlockState state, World worldIn, BlockPos pos, PlayerEntity player)

Called on a block when it is clicked by a player.

Note

This method is for when the player left-clicks on a block. Don’t get this confused with use, which is called when the player right-clicks.

Parameters:

Type	Name	Description
`BlockState`	`state`	The state of the block that was clicked
`World`	`worldIn`	The world that the block was clicked in
`BlockPos`	`pos`	The position of the block that was clicked
`PlayerEntity`	`player`	The player who did the clicking

Usage example

This method is perfect for adding custom events when a player clicks on a block.

By default, this method does nothing.
NoteBlock overrides this method so when left-clicked, it plays a sound. RedstoneOreBlock on left-click emits a faint light and spawns particles around itself.

`playerWillDestroy`

public void playerWillDestroy(World worldIn, BlockPos pos, BlockState state, PlayerEntity player)

Called before the Block is set to air in the world. Called regardless of if the player’s tool can actually collect this block.

Parameters:

Type	Name	Description
`World`	`worldIn`	The world that the block was destroyed
`BlockPos`	`pos`	The position of the block that was destroyed
`BlockState`	`state`	The state of the block that was destroyed
`PlayerEntity`	`player`	The player who harvested the block

Usage example

This method is perfect for adding custom events as a result of a player destroying a block

This method has important behavior in the Block class so be sure to call the super method.

super.playerWillDestroy(worldIn, pos, state, player);

The TNTBlock overrides this method to cause it’s explosion when a player destroys it if its unstable property is true.
This method is used by extended pistons; since an extended piston is made up of two blocks. (the extended head and the base) The PistonHeadBlock makes use of this method to destroy the base block when the PistonHeadBlock is destroyed.

Entity Collision

`entityInside`

public void entityInside(BlockState state, World worldIn, BlockPos pos, Entity entityIn)

This method is called whenever an entity collides with the block.

Parameters:

Type	Name	Description
`BlockState`	`state`	The state of the block that was collided with
`World`	`worldIn`	The world where the collided block is located
`BlockPos`	`pos`	The position of the block that was collided with
`Entity`	`entityIn`	The entity who collided with the block

Usage examples

An example use of this method is by the CampfireBlock which uses this method to light those on fire that collide with the campfire.