在 Flutter/Dart 中定义 singleton 属性的最佳方法是什么？

Question

I am using flutter_easyLoading package for loaders in my flutter project. It says in the documentation that it creates a singleton and I have to define its properties only once somewhere and it would be available throughout the app. What is the best practice to define these properties?

Right now I am initializing its variables in a splash screen file like this.

class _SplashScreenState extends State<SplashScreen> {
  @override
  void didChangeDependencies() async {
    super.didChangeDependencies();
  EasyLoading.instance
    ..displayDuration = const Duration(milliseconds: 2000)
    ..indicatorType = EasyLoadingIndicatorType.fadingCircle
    ..loadingStyle = EasyLoadingStyle.dark;
 }

Should I do it this way or maybe define some util method for all these properties.

Answer 1

You can use a factory constructor implement singleton classes in dart.

This is a simple example adapted to this context

 class EasyLoadingSingleton { static final EasyLoadingSingleton _easyloading = EasyLoadingSingleton._internal(); factory EasyLoadingSingleton() { return _easyloading; } EasyLoadingSingleton._internal(); }