Passing List index Data to a Stateful Widget to load PDF document dynamically

Question

I am trying to pass the 'index' of a List to a Stateful Widget. But it is not working as the 'index' is not being recognized.

From where I am passing data:

onTap: () {
  Navigator.push(context,
    MaterialPageRoute(builder: (context) => DetailsPage(index)));
},

Where the data is being passed:

    class DetailsPage extends StatefulWidget {
       final int index;
       DetailsPage(this.index);
    
      @override
      _MyDetailsPage createState() => _MyDetailsPage();
    }
    
    class _MyDetailsPage extends State<DetailsPage> {
      bool _isLoading = true;
      PDFDocument document;
    
      @override
      void initState() {
        super.initState();
        loadDocument();
      }
    
      List locations = [
        Books(
            name: 'book name 1',
            Booklink:
            'https://storage.googleapis.com/school_books/Class9/ban/Bangla%20Sahitto.pdf'),
        Books(
            name: 'book name 2',
            Booklink:
            'https://storage.googleapis.com/school_books/Class9/ban/Bangla%20Sahitto.pdf')
      ];
    
      loadDocument() async {
        document = await PDFDocument.fromURL(locations[index].Booklink);
        setState(() => _isLoading = false);
      }
    
      @override
      Widget build(BuildContext context) {
        return MaterialApp(
          home: Scaffold(
            appBar: AppBar(),
            body: Center(
              child: _isLoading
                  ? Center(child: CircularProgressIndicator())
                  : PDFViewer(
                      document: document,
                      zoomSteps: 1,
                    ),
            ),
          ),
        );
      }
    }

Any idea what I am doing wrong here?

Answer 1

Because you pass the data from another page to use that object or variable you need to use widget then call your object or variable like this :

locations[widget.index]