CricularProgress Bar is not changing the state from isLoading variable-CodePudding

I have Page called ProductSearch and ProductGride if I navigate from search page to gride page isLoading is not updating from the future function of the viewmodel of grid page.

ProductGridePage

class ProductGridePage extends StatefulWidget {
  @override
  _ProductGridePageState createState()=> _ProductGridePageState();
}


class _ProductGridePageState extends State<ProductGridePage>{
  int page_no=1;
  int page_size=20;
  bool isLoading=true;

  void fetchData() async {
    Provider.of<ProductgridVM>(context,listen: false).fetchProductGridList(
        productcode: productcode,
        branchname: branchname,
        metalname: metalname,
        purityname: purityname,
        seriesname: seriesname,
        producttypename: producttypename,
        collectionname: collectionname,
        categoriesname: categoriesname,
        makingProcessname: makingProcessname,
        page_no: page_no, page_size: page_size).then((value) => isLoading=false);
  }

  @override
  void initState() {
    super.initState();
    _controller = new TextEditingController(text: '1');
    fetchData();
  }



  @override
  Widget build(BuildContext context) {
    print(isLoading);
    return isLoading?Center(child: CircularProgressIndicator())
        : Scaffold(
      body: Column(
        children: [
         ]
    );
  }

}

CodePudding user response：

Put isLoading = false into the setState method after then or else you can call that in .whenComplete

void fetchData() async {
    Provider.of<ProductgridVM>(context,listen: false).fetchProductGridList(
        productcode: productcode,
        branchname: branchname,
        metalname: metalname,
        purityname: purityname,
        seriesname: seriesname,
        producttypename: producttypename,
        collectionname: collectionname,
        categoriesname: categoriesname,
        makingProcessname: makingProcessname,
        page_no: page_no, page_size: page_size).then((value) => setState((){
isLoading=false;})}

CodePudding user response：

The isLoading state is not changing. You need to change the state of it. Try as follows

void fetchData() async {
Provider.of<ProductgridVM>(context,listen: false).fetchProductGridList(
    productcode: productcode,
    branchname: branchname,
    metalname: metalname,
    purityname: purityname,
    seriesname: seriesname,
    producttypename: producttypename,
    collectionname: collectionname,
    categoriesname: categoriesname,
    makingProcessname: makingProcessname,
    page_no: page_no, page_size: page_size).then((value) {
    /// You need to change the state like this

    setState((){
isLoading=false});
}
    );
     }

CodePudding user response：

You can use setstate() to update the state. After navigating to the other page setstate() will help you to react accordingly.

Wrap isLoading with setstate()