Dart APIunself_modelActivitysource source property Null safety String source inherited email is the email used by the Activity on the App. Implementation String get source => throw _privateConstructorUsedError; unself_model unself_model Activity source property Activity class Constructors Activity fromJson Properties accountId appId archiveId copyWith created extra hashCode id labels name runtimeType source sourceId targetId timestamp type updated Methods noSuchMethod toJson toString Operators operator ==