从 Flutter 中的另一个 dart 文件在有状态小部件 class 下使用 SetState 方法调用 void

Question

I have one class containing stateful widget called _DispState with ListView.builder which shows some text downloaded from server:

class Disp extends StatefulWidget {
  Disp({Key key, this.title}) : super(key: key);
  final String title;
  @override
  _DispState createState() => _DispState();
}


class _DispState extends State<Disp> {

void refresher() async {
    while (true) {
      update();  //void function which downloads data from server and stores them into global variable "var AllData"
      setState(() {
        zobrazitPracu(); //splits and separate data from variable AllData into "List mojaPraca"
      });
      await Future.delayed(Duration(milliseconds: 3000));
    }
  }

  void oneTimeRefresh() async {
    update();
    setState(() {
      zobrazitPracu();
    });
  }

@override
  void initState() {
    super.initState();
    refresher(); //starts refresher to update data from server every 3 seconds
  }

Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Disp'),
      ),
      body: Center(
        child: ListView.builder(
            //very long code to show items one by one from "List mojaPraca"
        )
      )
}

There is refresher() function which updates list every 3 seconds. But I have another stateful widget in another dart file called _mavacka which creates new items and sends them to server on button click. I would like to achieve updating list in _DispState right after sending new item to server. I can't just put that data into mojaPraca List because at first it need to get ID generated by server. I have function oneTimeRefresh() to do it but i can't find the way how to call it from button press event in _mavacka state(which is in another dart file). I have heard about some keys and voidcallbacks but i haven't find them helpful for me and even maybe didn't understand them well (if is one of these 2 ways correct way how to do that, please try to explain this to me step by step). I don't want to pass any data, just call that one function. I am new to flutter programming, so maybe i am doing it completely wrong. If so, please correct me. If not, please help me find out the way how to call oneTimeRefresh() by clicking on button in another state. If there is other, mmore efficient way how to update List mojaPraca and then setState in _DispState please tell me.

Thanks a lot:)

Answer 1

I have one class containing stateful widget called _DispState with ListView.builder which shows some text downloaded from server:

class Disp extends StatefulWidget {
  Disp({Key key, this.title}) : super(key: key);
  final String title;
  @override
  _DispState createState() => _DispState();
}


class _DispState extends State<Disp> {

void refresher() async {
    while (true) {
      update();  //void function which downloads data from server and stores them into global variable "var AllData"
      setState(() {
        zobrazitPracu(); //splits and separate data from variable AllData into "List mojaPraca"
      });
      await Future.delayed(Duration(milliseconds: 3000));
    }
  }

  void oneTimeRefresh() async {
    update();
    setState(() {
      zobrazitPracu();
    });
  }

@override
  void initState() {
    super.initState();
    refresher(); //starts refresher to update data from server every 3 seconds
  }

Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Disp'),
      ),
      body: Center(
        child: ListView.builder(
            //very long code to show items one by one from "List mojaPraca"
        )
      )
}

There is refresher() function which updates list every 3 seconds. But I have another stateful widget in another dart file called _mavacka which creates new items and sends them to server on button click. I would like to achieve updating list in _DispState right after sending new item to server. I can't just put that data into mojaPraca List because at first it need to get ID generated by server. I have function oneTimeRefresh() to do it but i can't find the way how to call it from button press event in _mavacka state(which is in another dart file). I have heard about some keys and voidcallbacks but i haven't find them helpful for me and even maybe didn't understand them well (if is one of these 2 ways correct way how to do that, please try to explain this to me step by step). I don't want to pass any data, just call that one function. I am new to flutter programming, so maybe i am doing it completely wrong. If so, please correct me. If not, please help me find out the way how to call oneTimeRefresh() by clicking on button in another state. If there is other, mmore efficient way how to update List mojaPraca and then setState in _DispState please tell me.

Thanks a lot:)