我刚开始飞镖,刚遇到一个我还不明白的问题。我写了这堂课:
class Currency {
final String symbol;
final String name;
// constants for all available Currencies
static const Currency EURO = const Currency._euro();
static const Currency POUND = const Currency._pound();
static const Currency DOLLAR = const Currency._dollar();
// All available currencies as a list
static const List<Currency> CURRENCIES = const [
EURO,
POUND,
DOLLAR,
];
// Default constructor
Currency(this.symbol, this.name);
// Named constructors
const Currency._euro() : this('€', 'Euro');
const Currency._pound() : this('£', 'British Pound');
const Currency._dollar() : this('\$', 'US Dollar');
// toString()
@override
String toString() => '$symbol ($name)';
}
使用此类时,例如使用下面的语句,我得到“初始化静态字段时的循环依赖”-error。
Currency currency = Currency.EURO;
任何人都可以向我解释发生了什么事吗?
我无法重现您的错误,但在您将其他人重定向到的构造函数之前缺少const
const Currency(this.symbol, this.name);