RangeError (index): Invalid value: Valid value range is empty: 0

Question

Widget build(context) {
    try{
      if (isFirst == true) {
        fetchImage();
        fetchCategories(context);
        isFirst = false;
      }
    }catch(Excepti         


        

Answer 1

There are quick-and-dirty answer, and proper answer

Quick-and-dirty

Use list?.elementAt() ?? "" for safe access to element of a list

Widget build(context) {
    try{
      if (isFirst == true) {
        fetchImage();
        fetchCategories(context);
        isFirst = false;
      }
    }catch(Exception){

    }

    return MaterialApp(
      home: Scaffold(
        backgroundColor: Colors.black,
        appBar: AppBar(
          title: Text('Lets see images!'),
        ),
        body: new Column(
          children: [
            new Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                new InkResponse(
                    child: new Column(
                      children: [
                        Padding(
                          padding: EdgeInsets.all(10.0),
                          child: new Image.asset(
                            catimages?.elementAt(0) ?? "",
                            width: 60.0,
                            height: 60.0,
                          ),
                        ),
                        new Text(
                          categoriesText?.elementAt(0) ?? "",
                          style: TextStyle(color: Colors.white),
                        ),
                      ],
                    ),
                    onTap: () {
                      debugPrint("on tv clikced");
                      widget.fetchApI.fetchSubCategories(context, 6);
                    }),
                new InkResponse(
                  child: new Column(
                    children: [
                      Padding(
                        padding: EdgeInsets.all(10.0),
                        child: new Image.asset(
                          catimages?.elementAt(1) ?? "",
                          width: 60.0,
                          height: 60.0,
                        ),
                      ),
                      new Text(
                        categoriesText?.elementAt(1) ?? "",
                        style: TextStyle(color: Colors.white),
                      ),
                    ],
                  ),
                  onTap: () {
                    debugPrint("on moview clicked");
                    widget. fetchApI.fetchSubCategories(context, 7);
                  },
                ),
                new InkResponse(
                  child: new Column(
                    children: [
                      Padding(
                        padding: EdgeInsets.all(10.0),
                        child: new Image.asset(
                          catimages?.elementAt(2) ?? "",
                          width: 60.0,
                          height: 60.0,
                        ),
                      ),
                      new Text(
                       categoriesText?.elementAt(2) ?? "",
                        style: TextStyle(color: Colors.white),
                      ),
                    ],
                  ),
                  onTap: () {
                    debugPrint("on news clicked");
                    widget.fetchApI.fetchSubCategories(context, 10);
                  },
                ),
                new InkResponse(
                  child: new Column(
                    children: [
                      Padding(
                        padding: EdgeInsets.all(10.0),
                        child: new Image.asset(catimages?.elementAt(3) ?? "",
                            width: 60.0, height: 60.0),
                      ),
                      new Text(
                        categoriesText?.elementAt(3) ?? "",
                        style: TextStyle(color: Colors.white),
                      ),
                    ],
                  ),
                  onTap: () {
                    debugPrint('on shows clicked');
                    widget.fetchApI.fetchSubCategories(context, 8);
                  },
                ),
                new InkResponse(
                  child: new Column(
                    children: [
                      Padding(
                        padding: EdgeInsets.all(10.0),
                        child: new Image.asset('assets/live_icon.png',
                            width: 60.0, height: 60.0),
                      ),
                      new Text(
                        'Live',
                        style: TextStyle(color: Colors.white),
                      ),
                    ],
                  ),
                  onTap: () {
                    debugPrint('on live clicked');
                  },
                ),
              ],
            ),
            ImageList(images,widget.fetchApI),
          ],
        ),
      ),
    );
  }
}

Proper answer

Frankly, if I were to review this code, even if it works seamlessly, I would reject this change, because of the structure/pattern this code is using is quite bad.

Please use FutureBuilder, StreamBuilder or ValueListenableBuilder instead, but you need to provide more code (especially fetchImage and fetchCategories) for us to help.