我需要Object?在 Flutter 的 Provider 狀態中保存一個 type 的值，但是我無法檢查它是否為空。
Object? _session = {};
Object? get session => _session;
set session(Object? newValue) {
_session = newValue;
notifyListeners();
}
然后在小部件中
AppStateContent content = Provider.of<AppStateContent>(context);
content.session.isEmpty回報_The getter 'isEmpty' isn't defined for the type 'Object'.
當會話物件未修改時，content.session != {}不會回傳小部件。EmptyScreen()
content.session != {}
? const CurrentScreen()
: const EmptyScreen(),
uj5u.com熱心網友回復：
嘗試將其保留為空。
Object? _session;
Object? get session => _session;
set session(Object? newValue) {
_session = newValue;
notifyListeners();
}
content.session != null
? const CurrentScreen()
: const EmptyScreen(),
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