Events

CustomCrafterAPI Events

CustomCrafterAPI fires several custom events that implement Bukkit’s Event. These can be listened to and handled in the same way as ordinary Bukkit events.

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RegisterCustomRecipeEvent

Fired when a recipe is about to be registered via CustomCrafterAPI.registerRecipe(). Implements Cancellable; cancelling the event causes the recipe registration to fail.

Property	Type	Description
recipes	List<CRecipe>	The list of recipes that are about to be registered

class RecipeRegisterListener : Listener {
    @EventHandler
    fun onRegister(event: RegisterCustomRecipeEvent) {
        event.recipes.forEach { recipe ->
            println("Recipe registered: ${recipe.name}")
        }

        // Example: cancel registration of recipes whose name starts with "forbidden-"
        if (event.recipes.any { it.name.startsWith("forbidden-") }) {
            event.isCancelled = true
            println("Registration cancelled.")
        }
    }
}

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UnregisterCustomRecipeEvent

Fired when a recipe is about to be unregistered via CustomCrafterAPI.unregisterRecipe() or CustomCrafterAPI.unregisterAllRecipes(). Implements Cancellable; cancelling the event causes the recipe unregistration to fail.

Property	Type	Description
recipes	List<CRecipe>	The list of recipes that are about to be unregistered

class RecipeUnregisterListener : Listener {
    @EventHandler
    fun onUnregister(event: UnregisterCustomRecipeEvent) {
        event.recipes.forEach { recipe ->
            println("Recipe unregistered: ${recipe.name}")
        }

        // Example: prevent a specific recipe from being unregistered
        if (event.recipes.any { it.name == "protected-recipe" }) {
            event.isCancelled = true
        }
    }
}

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CreateCustomItemEvent

Fired when an item is crafted (i.e., a craft operation is executed). This event is not cancellable.

Property	Type	Description
player	Player	The player who performed the craft
view	CraftView	The UI input state at the time of crafting
result	Search.SearchResult?	The search result. null indicates the craft did not succeed
shiftUsed	Boolean	Whether the player bulk-crafted by holding Shift (since 5.0.17)
isAsync	Boolean	Whether the call originated from an asynchronous thread (since 5.0.17)

class CreateItemListener : Listener {
    @EventHandler
    fun onCreateItem(event: CreateCustomItemEvent) {
        val result = event.result ?: return

        // Log the name of the custom recipe that was crafted
        result.customs().forEach { (recipe, _) ->
            println("${event.player.name} crafted ${recipe.name}.")
        }

        // Example: perform additional processing when bulk-crafting
        if (event.shiftUsed) {
            println("Bulk crafting was used.")
        }
    }
}

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CustomCrafterAPIPropertiesChangeEvent

Fired when a mutable property (configuration value) of CustomCrafterAPI is changed. Both the old and new values are included.

This event is generic and carries the type T of the changed property.

Property	Type	Description
propertyName	String	The name of the changed property
oldValue	Property<T>	The value before the change
newValue	Property<T>	The value after the change
isAsync	Boolean	Whether the change originated from an asynchronous thread

To extract a value from Property<T> in a type-safe manner, use PropertyKey<T>.

val key = CustomCrafterAPIPropertiesChangeEvent.PropertyKey.BASE_BLOCK
val value: Material? = property.getOrNull(key)

The predefined PropertyKey values are as follows:

Key	Corresponding Type	Corresponding Property
RESULT_GIVE_CANCEL	Boolean	ResultGiveCancel
BASE_BLOCK	Material	BaseBlock
USE_MULTIPLE_RESULT_CANDIDATE_FEATURE	Boolean	UseMultipleResultCandidateFeature
USE_CUSTOM_CRAFT_UI	Boolean	UseCustomCraftUI
BASE_BLOCK_SIDE	Int	BaseBlockSide
CRAFT_UI_DESIGNER	CraftUIDesigner	CraftUIDesigner

Example: Detecting a Base Block Change

class PropertiesChangeListener : Listener {
    @EventHandler
    fun <T> onPropertiesChange(event: CustomCrafterAPIPropertiesChangeEvent<T>) {
        val key = CustomCrafterAPIPropertiesChangeEvent.PropertyKey.BASE_BLOCK

        // Filter to only the relevant event by property name
        if (event.propertyName != key.propertyName) return

        val oldBlock: Material = event.oldValue.getOrNull(key) ?: return
        val newBlock: Material = event.newValue.getOrNull(key) ?: return

        println("Base block changed from ${oldBlock.name} to ${newBlock.name}.")
    }
}

Example: Monitoring Multiple Properties Together

class AllPropertiesChangeListener : Listener {
    @EventHandler
    fun <T> onPropertiesChange(event: CustomCrafterAPIPropertiesChangeEvent<T>) {
        when (event.propertyName) {
            CustomCrafterAPIPropertiesChangeEvent.PropertyKey.BASE_BLOCK.propertyName -> {
                val newValue = event.newValue.getOrNull(
                    CustomCrafterAPIPropertiesChangeEvent.PropertyKey.BASE_BLOCK
                )
                println("Base block changed: $newValue")
            }
            CustomCrafterAPIPropertiesChangeEvent.PropertyKey.USE_CUSTOM_CRAFT_UI.propertyName -> {
                val newValue = event.newValue.getOrNull(
                    CustomCrafterAPIPropertiesChangeEvent.PropertyKey.USE_CUSTOM_CRAFT_UI
                )
                println("Custom UI enabled: $newValue")
            }
        }
    }
}