How can I add navigation code to flutter list view?

I am having trouble inserting navigation links within my code below. I would like to learn how to insert navigation links within the second

onPressed: () {

//TODO(implement). }

The ListView Widgets: Approved, Pending etc are the items that should contain links to other pages. The pages will be accessed by clicking on the FontAwesome.chevronRight

import 'package:flutter/material.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';

class AppTab2 extends StatefulWidget {
  @override
  _AppTab2State createState() => _AppTab2State();
}

class _AppTab2State extends State<AppTab2> {
  PageController _pageController = PageController(initialPage: 2);

  @override
  build(BuildContext context) {
    final Map<String, Widget> pages = <String, Widget>{
      'My Music': Center(
        child: Text('My Music not implemented'),
      ),
      'Shared': Center(
        child: Text('Shared not implemented'),
      ),
      'Feed': Feed(),
    };
    TextTheme textTheme = Theme.of(context).textTheme;
    return Stack(
      children: [
        Container(
          decoration: BoxDecoration(
              // Gradient color the background
              gradient: LinearGradient(
            begin: FractionalOffset.topCenter,
            end: FractionalOffset.bottomCenter,
            colors: [
              const Color.fromARGB(255, 253, 72, 72),
              const Color.fromARGB(255, 87, 97, 249),
            ],
            stops: [0.0, 1.0],
          )),
//          child: Align(
//            alignment: FractionalOffset.bottomCenter,
//            child: Container(
//              padding: const EdgeInsets.all(10.0),
//              child: Text(
//                'Demo',
//                style: textTheme.headline.copyWith(
//                  color: Colors.grey.shade800.withOpacity(0.8),
//                  fontWeight: FontWeight.bold,
//                ),
//              ),
//            ),
//          ),
        ),
        Scaffold(
          backgroundColor: Colors.white,
//          appBar: AppBar(
//            backgroundColor: const Color(0x00000000),
//            elevation: 0.0,
//            leading: Center(
//              child: ClipOval(
//                child: Image.network(
//                  'http://i.imgur.com/TtNPTe0.jpg',
//                ),
//              ),
//            ),
//            actions: [
//              IconButton(
//                icon: Icon(Icons.add),
//                onPressed: () {
//                  // TODO: implement
//                },
//              ),
//            ],
////            title: const Text('tofu\'s songs'),
//            bottom: CustomTabBar(
//              pageController: _pageController,
//              pageNames: pages.keys.toList(),
//            ),
//          ),
          body: PageView(
            controller: _pageController,
            children: pages.values.toList(),
          ),
        ),
      ],
    );
  }
}

class CustomTabBar extends AnimatedWidget implements PreferredSizeWidget {
  CustomTabBar({this.pageController, this.pageNames})
      : super(listenable: pageController);

  final PageController pageController;
  final List<String> pageNames;

  @override
  final Size preferredSize = Size(0.0, 40.0);

  @override
  Widget build(BuildContext context) {
    TextTheme textTheme = Theme.of(context).textTheme;
    return Container(
      height: 40.0,
      margin: const EdgeInsets.all(10.0),
      padding: const EdgeInsets.symmetric(horizontal: 20.0),
      decoration: BoxDecoration(
        color: Colors.grey.shade800.withOpacity(0.5),
        borderRadius: BorderRadius.circular(20.0),
      ),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: List.generate(pageNames.length, (int index) {
          return InkWell(
              child: Text(pageNames[index],
                  style: textTheme.subhead.copyWith(
                    fontSize: 30.0,
                    fontFamily: 'OpenSans',
                    color: Colors.white.withOpacity(
                      index == pageController.page ? 1.0 : 0.2,
                    ),
                  )),
              onTap: () {
                pageController.animateToPage(
                  index,
                  curve: Curves.easeOut,
                  duration: const Duration(milliseconds: 300),
                );
              });
        }),
      ),
    );
  }
}

class Feed extends StatefulWidget {
  @override
  _FeedState createState() => _FeedState();
}

class _FeedState extends State<Feed> {
  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        Content(
          title: 'Approved',
        ),
        Content(
          title: 'Pending',
        ),
        Content(
          title: 'Published',
        ),
        Content(
          title: 'Withdrawn',
        ),
        Content(
          title: 'Declined',
        ),
        Content(
          title: 'Content Rights',
        ),
      ],
    );
  }
}

class Content extends StatefulWidget {
  const Content({
    this.title,
  });

  final String title;

  @override
  _ContentState createState() => _ContentState();
}

class _ContentState extends State<Content> {
  @override
  Widget build(BuildContext context) {
    TextTheme textTheme = Theme.of(context).textTheme;
    return Container(
        margin: const EdgeInsets.symmetric(horizontal: 10.0, vertical: 5.0),
        padding: const EdgeInsets.symmetric(horizontal: 15.0, vertical: 10.0),
        decoration: BoxDecoration(
          color: Colors.grey.shade300.withOpacity(0.5),
          borderRadius: BorderRadius.circular(5.0),
        ),
        child: IntrinsicHeight(
          child: Row(
            children: <Widget>[
//              Container(
//                margin:
//                    const EdgeInsets.only(top: 4.0, bottom: 4.0, right: 10.0),
//                child: CircleAvatar(
//                  backgroundImage: NetworkImage(
//                      'http://thecatapi.com/api/images/get?format=src'
//                      '&size=small&type=jpg#${title.hashCode}'),
//                  radius: 20.0,
//                ),
//              ),
              SizedBox(
                height: 15.0,
              ),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                  children: <Widget>[
                    Text(widget.title, style: textTheme.subhead),
                  ],
                ),
              ),
              Container(
                margin: EdgeInsets.symmetric(horizontal: 5.0),
                child: InkWell(
                  child: Icon(
                    FontAwesomeIcons.chevronRight,
                    size: 25.0,
                    color: Colors.deepPurpleAccent,
                  ),
                  onTap: () {
                    // TODO(implement)
                  },
                ),
              ),
              Container(
                margin: EdgeInsets.symmetric(horizontal: 5.0),
                child: InkWell(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: <Widget>[
//                      Icon(Icons.favorite, size: 25.0),
//                      Text('${likes ?? ''}'),
                    ],
                  ),
                  onTap: () {
                    // TODO(implement)
                  },
                ),
              ),
            ],
          ),
        ));
  }
}

There are some bug in your code. for demo purpose, I modify some of your code.
you can see full demo code and picture below

code snippet

child: ListView(
        children: [
          Content(
            title: 'Approved',
            screenPage: Approved(),
          ),
          Content(
            title: 'Pending',
            screenPage: Pending(),
          ),
...
class Content extends StatefulWidget {
  const Content({
    this.title,
    this.screenPage,
  });

  final String title;
  final Widget screenPage;
...
onTap: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(builder: (context) => widget.screenPage),
                    );
                  },

full code

import 'package:flutter/material.dart';
import 'package:font_awesome_flutter/font_awesome_flutter.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Invoke "debug painting" (press "p" in the console, choose the
          // "Toggle Debug Paint" action from the Flutter Inspector in Android
          // Studio, or the "Toggle Debug Paint" command in Visual Studio Code)
          // to see the wireframe for each widget.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Feed(),
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.display1,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}



class AppTab2 extends StatefulWidget {
  @override
  _AppTab2State createState() => _AppTab2State();
}

class _AppTab2State extends State<AppTab2> {
  PageController _pageController = PageController(initialPage: 2);

  @override
  build(BuildContext context) {
    final Map<String, Widget> pages = <String, Widget>{
      'My Music': Center(
        child: Text('My Music not implemented'),
      ),
      'Shared': Center(
        child: Text('Shared not implemented'),
      ),
      'Feed': Feed(),
    };
    TextTheme textTheme = Theme.of(context).textTheme;
    return Stack(
      children: [
        Container(
          decoration: BoxDecoration(
            // Gradient color the background
              gradient: LinearGradient(
                begin: FractionalOffset.topCenter,
                end: FractionalOffset.bottomCenter,
                colors: [
                  const Color.fromARGB(255, 253, 72, 72),
                  const Color.fromARGB(255, 87, 97, 249),
                ],
                stops: [0.0, 1.0],
              )),
//          child: Align(
//            alignment: FractionalOffset.bottomCenter,
//            child: Container(
//              padding: const EdgeInsets.all(10.0),
//              child: Text(
//                'Demo',
//                style: textTheme.headline.copyWith(
//                  color: Colors.grey.shade800.withOpacity(0.8),
//                  fontWeight: FontWeight.bold,
//                ),
//              ),
//            ),
//          ),
        ),
        Scaffold(
          backgroundColor: Colors.white,
//          appBar: AppBar(
//            backgroundColor: const Color(0x00000000),
//            elevation: 0.0,
//            leading: Center(
//              child: ClipOval(
//                child: Image.network(
//                  'http://i.imgur.com/TtNPTe0.jpg',
//                ),
//              ),
//            ),
//            actions: [
//              IconButton(
//                icon: Icon(Icons.add),
//                onPressed: () {
//                  // TODO: implement
//                },
//              ),
//            ],
////            title: const Text('tofu\'s songs'),
//            bottom: CustomTabBar(
//              pageController: _pageController,
//              pageNames: pages.keys.toList(),
//            ),
//          ),
          body: PageView(
            controller: _pageController,
            children: pages.values.toList(),
          ),
        ),
      ],
    );
  }
}

class CustomTabBar extends AnimatedWidget implements PreferredSizeWidget {
  CustomTabBar({this.pageController, this.pageNames})
      : super(listenable: pageController);

  final PageController pageController;
  final List<String> pageNames;

  @override
  final Size preferredSize = Size(0.0, 40.0);

  @override
  Widget build(BuildContext context) {
    TextTheme textTheme = Theme.of(context).textTheme;
    return Container(
      height: 40.0,
      margin: const EdgeInsets.all(10.0),
      padding: const EdgeInsets.symmetric(horizontal: 20.0),
      decoration: BoxDecoration(
        color: Colors.grey.shade800.withOpacity(0.5),
        borderRadius: BorderRadius.circular(20.0),
      ),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: List.generate(pageNames.length, (int index) {
          return InkWell(
              child: Text(pageNames[index],
                  style: textTheme.subhead.copyWith(
                    fontSize: 30.0,
                    fontFamily: 'OpenSans',
                    color: Colors.white.withOpacity(
                      index == pageController.page ? 1.0 : 0.2,
                    ),
                  )),
              onTap: () {
                pageController.animateToPage(
                  index,
                  curve: Curves.easeOut,
                  duration: const Duration(milliseconds: 300),
                );
              });
        }),
      ),
    );
  }
}

class Approved extends StatefulWidget {
  @override
  _ApprovedState createState() => _ApprovedState();
}

class _ApprovedState extends State<Approved> {
  @override
  Widget build(BuildContext context) {
    return Text('Approved');
  }
}

class Pending extends StatefulWidget {
  @override
  _PendingState createState() => _PendingState();
}

class _PendingState extends State<Pending> {
  @override
  Widget build(BuildContext context) {
    return Text('Pending');
  }
}

class Feed extends StatefulWidget {
  @override
  _FeedState createState() => _FeedState();
}

class _FeedState extends State<Feed> {
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 300,
      child: ListView(
        children: [
          Content(
            title: 'Approved',
            screenPage: Approved(),
          ),
          Content(
            title: 'Pending',
            screenPage: Pending(),
          ),
          Content(
            title: 'Published',
          ),
          Content(
            title: 'Withdrawn',
          ),
          Content(
            title: 'Declined',
          ),
          Content(
            title: 'Content Rights',
          ),
        ],
      ),
    );
  }
}

class Content extends StatefulWidget {
  const Content({
    this.title,
    this.screenPage,
  });

  final String title;
  final Widget screenPage;

  @override
  _ContentState createState() => _ContentState();
}

class _ContentState extends State<Content> {
  @override
  Widget build(BuildContext context) {
    TextTheme textTheme = Theme.of(context).textTheme;
    return Container(
        margin: const EdgeInsets.symmetric(horizontal: 10.0, vertical: 5.0),
        padding: const EdgeInsets.symmetric(horizontal: 15.0, vertical: 10.0),
        decoration: BoxDecoration(
          color: Colors.grey.shade300.withOpacity(0.5),
          borderRadius: BorderRadius.circular(5.0),
        ),
        child: IntrinsicHeight(
          child: Row(
            children: <Widget>[
              Text("this is Content"),
//              Container(
//                margin:
//                    const EdgeInsets.only(top: 4.0, bottom: 4.0, right: 10.0),
//                child: CircleAvatar(
//                  backgroundImage: NetworkImage(
//                      'http://thecatapi.com/api/images/get?format=src'
//                      '&size=small&type=jpg#${title.hashCode}'),
//                  radius: 20.0,
//                ),
//              ),
              SizedBox(
                height: 15.0,
              ),
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                  children: <Widget>[
                    Text(widget.title, style: textTheme.subhead),
                  ],
                ),
              ),
              Container(
                margin: EdgeInsets.symmetric(horizontal: 5.0),
                child: InkWell(
                  child: Icon(
                    FontAwesomeIcons.chevronRight,
                    size: 25.0,
                    color: Colors.deepPurpleAccent,
                  ),
                  onTap: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(builder: (context) => widget.screenPage),
                    );
                  },
                ),
              ),
              Container(
                margin: EdgeInsets.symmetric(horizontal: 5.0),
                child: InkWell(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: <Widget>[
//                      Icon(Icons.favorite, size: 25.0),
//                      Text('${likes ?? ''}'),
                    ],
                  ),
                  onTap: () {
                    // TODO(implement)
                  },
                ),
              ),
            ],
          ),
        ));
  }
}