import 'package:flutter/material.dart';

void main(){
  runApp(GestureSwipeApp());
}

class GestureSwipeApp extends StatelessWidget{
  @override
  Widget build(BuildContext context){
    return MaterialApp(
      title:'Swipe Detector',
      home:SwipePage(),
    );
  }
}

class SwipePage extends StatefulWidget{
  @override
  _SwipePageState createState()=>_SwipePageState();
}

class _SwipePageState extends State<SwipePage>{
  String _gestureText='Swipe horizontally or double tap';

  void _onHorizontalDragEnd(DragEndDetails details){
    setState((){
      _gestureText='Swipe Detected';
    });
  }

  void _onDoubleTap(){
    setState((){
      _gestureText='Double Tap Detected';
    });
  }

  @override
  Widget build(BuildContext context){
    return Scaffold(
      appBar:AppBar(title:Text('Gesture Detector')),
      body:Center(
        child:GestureDetector(
          onHorizontalDragEnd: _onHorizontalDragEnd,
          onDoubleTap:_onDoubleTap,
          child:Container(
            padding:EdgeInsets.all(40),
            color:Colors.lightGreen.shade200,
            child:Text(
              _gestureText,
              style:TextStyle(fontSize:24),
            ),
          ),
        ),
      ),
    );
    }
  }