将快照数据传递到Flutter Widget

问题描述

我试图将数据从快照传递到小部件，以便可以呈现数据，但出现以下错误

lib/screens/RetailerList.dart:215:35: Error: Too few positional arguments: 1 required,0 given.
                  ? _buildretailer(retailer: snapshot.data)

小部件

Widget _buildretailer(Retailer retailer) {
    return GestureDetector(
      onTap: () {
        Navigator.of(context).push(
          MaterialPageRoute(
              // builder: (_) => RetailerDetails(retailer: retailer[0]),),);
      },child: Padding(
        padding: EdgeInsets.only(left: 40.0,bottom: 30.0),child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,children: <Widget>[
            Hero(
              tag: retailer.slug,child: Container(
                width: double.infinity,height: 250.0,decoration: Boxdecoration(
                  borderRadius: BorderRadius.only(
                    topLeft: Radius.circular(20.0),bottomLeft: Radius.circular(20.0),image: decorationImage(
                    image: NetworkImage(
                      "https://site-assets.afterpay.com/assets/favicon/apple-touch-icon-47062a004c5b1440ea8159b43580154540d76df61dc55dc87522378f8f76bbec.png",fit: BoxFit.cover,Padding(
              padding: EdgeInsets.fromLTRB(12.0,12.0,40.0,0.0),child: Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,children: <Widget>[
                  Text(
                    retailer.name,style: TextStyle(
                      fontFamily: 'Montserrat',fontSize: 24.0,fontWeight: FontWeight.bold,IconButton(
                    icon: Icon(Icons.favorite_border),iconSize: 30.0,color: Color(0xFFFD6456),onpressed: () => print('Favorite'),],0.0,12.0),child: Text(
                retailer.shortDescription,style: TextStyle(
                  fontFamily: 'Montserrat',fontSize: 16.0,color: Colors.grey,);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: Theme.of(context).platform == TargetPlatform.iOS
          ? CupertinoNavigationBar(
              actionsForegroundColor: Color.fromrGBO(108,212,196,1),middle: Text('Explore Retailers',style: GoogleFonts.nunito(
                      fontWeight: FontWeight.w700,textStyle: TextStyle(
                          color: Color.fromrGBO(98,49,158,letterSpacing: .5,fontSize: 20))),leading: IconButton(
                tooltip: 'Filter Retailers',icon: Icon(IconData(0xF4A6,fontFamily: CupertinoIcons.iconFont,fontPackage: CupertinoIcons.iconFontPackage)),// onpressed: _onButtonpressed
              ),)
          : AppBar(
              title: Text('Explore Retailers',style: GoogleFonts.nunito(fontWeight: FontWeight.w700)),actions: <Widget>[
                IconButton(
                  tooltip: 'Filter Retailers',icon: Icon(Icons.filter_list),// onpressed: _onButtonpressed
                )
              ],backgroundColor: Colors.white,body: ListView(
        children: <Widget>[
          SizedBox(height: 10.0),Container(height: 100.0,child: _buildListView()),SizedBox(height: 50.0),StreamBuilder<List<Retailer>>(
            stream: fetchRetailers().asstream(),builder: (context,snapshot) {
              if (snapshot.hasError) print(snapshot.error);
              return snapshot.hasData
                  ? _buildretailer(retailer: snapshot.data)
                  : Center(child: CircularProgressIndicator());
            },)
        ],);
  }
}

解决方法

代替buildRetailer(retailer: snapshot.data)

执行buildRetailer(snapshot.data)

由于您要将数据传递给不存在的命名参数retailer，因为您已经在positional parameter方法中定义了buildRetailer

flutter-widget snapshot