picker doesn't update adapter start/end values in setState

[fatimahossny]

I use picker as a widget and i want to update adapter start & end to new value every time the user click on button ,
but it only keeps the first values it's get, i even try with state to call setState but it still not working . here is my code any help is appreciated

class _MyHomePageState extends State<MyHomePage> {
  int start = 0;
  int end = 5;

  void _updatePicker() {
    setState(() {
      start = 12;
      end = 24;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Picker(
            adapter: NumberPickerAdapter(data: [
              NumberPickerColumn(begin: start, end: end),
              NumberPickerColumn(begin: 0, end: 59),
            ]),
            delimiter: null,
            hideHeader: true,
            itemExtent: 32.0,
            height: 120.0,
            textScaleFactor: 1.1,
            columnPadding: EdgeInsets.all(6.0),
            selectedTextStyle: TextStyle(color: Colors.blue, fontSize: 18.0),
            onSelect: (Picker picker, int i, List value) {
              print(picker.getSelectedValues());
              List selectedValues = picker.getSelectedValues();
            }).makePicker(ThemeData(
          backgroundColor: Colors.white,
        )),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _updatePicker,
        child: Icon(Icons.access_time),
      ),
    );
  }
}

[williams-gunawan]

you @fatimahossny can try this, this is not the efficient one, but kinda like workaround

short Explanation: this will force picker widget to force reload, do note that you must wrap one of your picker inside other widget on futureBuilder like the example below.
sorry for my bad english :')

class _MyHomePageState extends State<MyHomePage> {
  int start = 0;
  int end = 5;
  Future forceRebuild = Future.delayed(Duration.zero);
  void _updatePicker() {
    setState(() {
      start = 12;
      end = 24;
       forceRebuild = Future.delayed(Duration.zero);
    });
  }

  @override
  Widget build(BuildContext context) {
   ....
      body: Center(
        child: FutureBuilder(
            future: forceRefreshLuasBangunan,
            builder: (context, snapshot) {
              if (snapshot.connectionState == ConnectionState.waiting) 
                return Container(
                             child: {YourNumberPicker}
                );
              return {YourNumberPicker};
      ),
      .....
}

[yangyxd]

Thanks! I've fixed this bug.

[doanbh]

Thanks! I've fixed this bug.

I've setState but NumberPickerAdapter keep end with count of old state.