unreal.FieldNotificationLibrary

class unreal.FieldNotificationLibrary(outer: Object | None = None, name: Name | str = 'None')

Bases: BlueprintFunctionLibrary

The Field Notification system allows a user to know when a property value is modified at runtime (note that it can be a function return value). The class needs to implement the INotifyFieldValueChanged interface. The property’ setter usually follows this pattern “if (new value != old value) assign the new value; broadcast that the value changed;”. The Blueprint implementation handles that setter logic automatically with SetPropertyValueAndBroadcast. When a property value is modified by replication, the RepNotify will call BroadcastFieldValueChanged. A function can also be a Field Notify. The function needs to be const and return a single value.

C++ Source:

  • Module: Engine

  • File: FieldNotificationLibrary.h

classmethod broadcast_field_value_changed(object, field_id) → None

Broadcast that the Field value changed.

Parameters:
classmethod broadcast_fields_value_changed(object, field_ids) → None

Broadcast that a list of Field values changed.

Parameters: