main.dart

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

void main() {
  runApp(MaterialApp(
    title: 'Navigation Basics',
    home: FirstScreen(items: List<String>.generate(40, (i) => "Item $i")),
  ));
}

class FirstScreen extends StatefulWidget {
  final List<String> items;
  FirstScreen({@required this.items});
  
  @override
  FirstScreenState createState() => FirstScreenState();
}

class FirstScreenState extends State<FirstScreen> {
  void addNextView(cxt) async {
    await Navigator.push(cxt, MaterialPageRoute(
      builder: (_) => SecondScreen(),
      settings: RouteSettings(name: '/nextView', isInitialRoute: false)
    ));
  }

  @override
  Widget build(BuildContext context) {
    print("building list");
    return Scaffold(
      appBar: AppBar(
        title: Text('First Screen'),
        actions: <Widget>[
            FlatButton(
              color: Colors.black,
              onPressed: (){ 
                this.addNextView(context);
              },
              child:
              Text("Click here to add next view", style: TextStyle(color: Colors.white))
            )
          ],
      ),
      body: 
      Column(
        mainAxisAlignment: MainAxisAlignment.start,
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          Container(
            child: Text("Label")
          ),
          Flexible(child: ListView.builder(
            primary: false,
            physics: BouncingScrollPhysics(),
            itemCount: widget.items.length,
            itemBuilder: (context, index) {
              return Slidable(
                  key: Key(index.toString()),
                  delegate: SlidableBehindDelegate(),  
                  actionExtentRatio: 0.2, 
                  child: Container(
                    height: 90.0,
                    child: Text('${widget.items[index]}')
                  ),
                  showAllActionsThreshold: 0.35,
                  secondaryActions: <Widget>[
                    SlideAction(
                      onTap: () => {},
                      color: Color.fromRGBO(51, 217, 178,1.0),
                      child: Column(
                        mainAxisAlignment: MainAxisAlignment.center,
                        children: [
                          Icon(Icons.add_circle, color: Color.fromRGBO(33, 140, 116,1.0)),
                          Padding(
                            padding: EdgeInsets.only(top: 5.0),
                            child: Text("Queue", style: TextStyle(fontWeight: FontWeight.w500, color: Color.fromRGBO(33, 140, 116,1.0)))
                          )
                        ] 
                      )
                    )
                  ],
              );
            },
          ))
        ]
      )
    );
  }
}

class SecondScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Second Screen"),
      ),
      body: Center(
        child: RaisedButton(
          onPressed: () {
            Navigator.pop(context);
          },
          child: Text('Go back!'),
        ),
      ),
    );
  }
}