Block Interaction/1.18
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 InteractionResult use(BlockState state, Level level, BlockPos pos, Player player, InteractionHand hand, BlockHitResult hit)
This is the method that controls right click behavior.
Parameters
| Type | Name | Description |
|---|---|---|
BlockState |
state |
The state of the block that was clicked |
Level |
level |
The level that the block was clicked in |
BlockPos |
pos |
The position of the block that was clicked |
Player |
player |
The player who did the clicking |
InteractionHand |
handIn |
The hand with which the player clicked |
BlockHitResult |
hit |
Where on the block's bounds it was hit |
Return Value
InteractionResult is the result right clicking, see example usages below. InteractionResult.SUCCESS means the right click action was successful. InteractionResult.CONSUME means that the right click action was consumed. InteractionResult.CONSUME_PARTIAL means that the right click action is being consumed. InteractionResult.PASS is the default behavior, for when the block has no right click behavior, and allows something else to handle the right click. InteractionResult.FAIL means that the action failed.
| Enum Value | Example Usage |
|---|---|
SUCCESS |
Eating a slice of cake. |
CONSUME |
Tuning a noteblock. |
CONSUME_PARTIAL |
Eating a carrot. |
PASS |
When right-clicking dirt. Or any other basic block. |
FAIL |
When attempting to place a minecart on a block other than rails. |
Important
InteractionResult.CONSUME from this method on the client will prevent it being called on the server. It is common practice to just check level.isClientSide and return InteractionResult.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.
Screens
One of the most common things to do on block activation is opening a Screen. 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 AbstractContainerMenus and modifying the level, should only be done on the server-side.
= Block Placement
setPlacedBy
public void setPlacedBy(Level level, BlockPos pos, BlockState state, @Nullable LivingEntity placer, ItemStack stack)
Called by BlockItems after a block is set in the level, to allow post-place logic.
Parameters
| Type | Name | Description |
|---|---|---|
Level |
level |
The level 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, Level level, BlockPos pos, Player player)
Called on a block when it is clicked by a player.
Info
This method is for when the player left-clicks on a block.
use, which is called when the player right-clicks.Parameters
| Type | Name | Description |
|---|---|---|
BlockState |
state |
The state of the block that was clicked |
Level |
level |
The level that the block was clicked in |
BlockPos |
pos |
The position of the block that was clicked |
Player |
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.
Two blocks that override this method are the NoteBlock and the RedstoneOreBlock.
NoteBlock override this method so that when left-clicked, it plays a sound.
RedStoneOreBlock overrides this method so that when left-clicked, it gives off emits faint light for a few seconds.
playerWillDestroy
public void playerWillDestroy(Level level, BlockPos pos, BlockState state, Player player)
Called before the Block is set to air in the level. Called regardless of if the player's tool can actually collect this block.
Parameters
| Type | Name | Description |
|---|---|---|
Level |
level |
The level 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 |
Player |
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(level, 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 moving head is destroyed.
Entity Collision
entityInside
public void entityInside(BlockState state, Level level, BlockPos pos, Entity entity)
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 |
Level |
level |
The level where the collided block is located |
BlockPos |
pos |
The position of the block that was collided with |
Entity |
entity |
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.