import 'dart:async'; import "package:photos/models/location/location.dart"; typedef FutureVoidCallback = Future Function(); typedef BoolCallBack = bool Function(); typedef FutureVoidCallbackParamStr = Future Function(String); typedef VoidCallbackParamStr = void Function(String); typedef FutureOrVoidCallback = FutureOr Function(); typedef VoidCallbackParamInt = void Function(int); typedef VoidCallbackParamLocation = void Function(Location); typedef VoidCallbackParamListDouble = void Function(List);