我是新手,可以通过youtube上有关notodo_app的教程来学习。因此我遵循相同的代码,并且已经尝试重写几乎所有内容,但是当我开始使用initstate,setstate时。
与setstate相关的代码
final List<NoDoItem> _itemList = <NoDoItem>[];
@override
void initState() {
super.initState();
_readNoDoList();
}
void _handleSubmitted(String text) async {
_textEditingController.clear();
NoDoItem noDoItem = NoDoItem(text, DateTime.now().toIso8601String());
int savedItemId = await db.saveItem(noDoItem);
NoDoItem addedItem = await db.getItem(savedItemId);
setState(() {
_itemList.insert(0, addedItem);
});
print("Item saved id: $savedItemId");
}
_readNoDoList() async {
List items = await db.getItems();
items.forEach((item) {
NoDoItem noDoItem = NoDoItem.map(item);
print("Db items: ${noDoItem.itemName}");
});
}
我收到此错误,并且没有提交任何东西,如果使用的是模拟器,它将自动关闭。
E/flutter (23633): [ERROR:flutter/shell/common/shell.cc(184)] Dart Error: Unhandled exception:
E/flutter (23633): Stack Overflow
E/flutter (23633): #0 _Completer.completeError (dart:async/future_impl.dart:19:3)
E/flutter (23633): #1 _RootZone.runBinary (dart:async/zone.dart:1384:54)
E/flutter (23633): #2 _FutureListener.handleError (dart:async/future_impl.dart:143:20)
E/flutter (23633): #3 Future._propagateToListeners.handleError (dart:async/future_impl.dart:654:47)
E/flutter (23633): #4 Future._propagateToListeners (dart:async/future_impl.dart:675:24)
E/flutter (23633): #5 Future._completeError (dart:async/future_impl.dart:494:5)
E/flutter (23633): #6 _SyncCompleter._completeError (dart:async/future_impl.dart:55:12)
E/flutter (23633): #7 _Completer.completeError (dart:async/future_impl.dart:27:5)
E/flutter (23633): #8 _RootZone.runBinary (dart:async/zone.dart:1384:54)
E/flutter (23633): #9 _FutureListener.handleError (dart:async/future_impl.dart:143:2
答案 0 :(得分:0)
您遵循的示例的 database_client.dart 文件存在错误,特别是导致递归/堆栈溢出异常。请将第22行上的代码从 return db; 更新为 return _db; ,它现在应该可以正常工作
Future<Database> get db async {
if (_db != null) {
return _db; // return db; throws a Stack Overflow Exception / recursion
}
_db = await initDb();
return _db;
}