​
Code Explained - The Unit Lists :

​import 'package:flutter/material.dart';
import '../Terms/terms1.dart';
import '../Terms/terms2.dart';
import '../Terms/terms3.dart';
import '../Terms/terms4.dart';
import '../Terms/terms5.dart';
import '../Terms/terms6.dart';
import 'page.dart';
import "./helpterms.dart";
class TermsList extends StatelessWidget {
  TermsList();
  @override
  Widget build(BuildContext context) {
    final title = 'Terms List';

    return MaterialApp(
      title: title,
      theme: new ThemeData(          // Add the 3 lines from here...

        primaryColor: Colors.orange[800],
        accentColor: Colors.orangeAccent[600],
      ),
      home: Scaffold(
        appBar: AppBar(
          title: Text(title),
          leading:  new IconButton(
              icon: new Icon(Icons.arrow_back),
              color: Colors.white,
              iconSize: 25.0,

              onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Page()), (Route route) => route == null)
          ),
        ),
        body: ListView(
          children: <Widget>[
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.account_balance),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms1()), (Route route) => route == null)
              ),
              title: Text('Unit One: The Basics'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms1())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.library_books),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms2()), (Route route) => route == null)
              ),
              title: Text('Unit Two: The Amendments'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms2())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.group),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms3()), (Route route) => route == null)
              ),
              title: Text('Unit Three: The Legislative Branch'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms3())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.gavel),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms4()), (Route route) => route == null)
              ),
              title: Text('Unit Four: The Judicial Branch'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms4())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.public),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms5()), (Route route) => route == null)
              ),
              title: Text('Unit Five: The Executive Branch'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms5())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.fingerprint),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new Terms6()), (Route route) => route == null)
              ),
              title: Text('Unit Six: Court Cases'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Terms6())),
            ),
            ListTile(
              leading:  new IconButton(
                  icon: new Icon(Icons.help_outline),
                  color: Colors.orangeAccent,
                  iconSize: 40.0,
                  //onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new LandingPage()), (Route route) => route == null)
                  onPressed: () => Navigator.of(context).pushAndRemoveUntil(new MaterialPageRoute(builder: (BuildContext context) => new HelpTerms()), (Route route) => route == null)
              ),
              title: Text('Help'),
              onTap: () => Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new HelpTerms())),
            ),
          ],
        ),
      ),
    );
  }
}

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