swipedetector_nullsafety

A Flutter package to detect up, down, left, right swipes. This package is null-safety version of swipedetector.

Getting Started

For help getting started with Flutter, view our online documentation.

Usage

Using SwipeDetector is straightforward, just wrap it around the Widget you want to detect swipes on.

SwipeDetector(
    child: ... //You Widget Tree here
    ),
    onSwipeUp: () {
        setState(() {
            _swipeDirection = "Swipe Up";
        });
    },
    onSwipeDown: () {
        setState(() {
            _swipeDirection = "Swipe Down";
        });
    },
    onSwipeLeft: () {
      setState(() {
        _swipeDirection = "Swipe Left";
      });
    },
    onSwipeRight: () {
      setState(() {
        _swipeDirection = "Swipe Right";
      });
    },
)

Configuration Options

In case you don't require the default configuration and want to tune the sensitivity of swipes, you can pass your own configuration values.

SwipeDetector(
    child: ... //You Widget Tree here
    ),
    onSwipeUp: ...
    onSwipeDown: ...
    onSwipeLeft: ...
    onSwipeRight: ...,
    swipeConfiguration: SwipeConfiguration(
      verticalSwipeMinVelocity: 100.0,
      verticalSwipeMinDisplacement: 50.0,
      verticalSwipeMaxWidthThreshold:100.0,
      horizontalSwipeMaxHeightThreshold: 50.0,
      horizontalSwipeMinDisplacement:50.0,
      horizontalSwipeMinVelocity: 200.0),
    ),
)

All the parameters are optional, so you can register for any swipe direction and provide any configuration value.

Here is a simple example. Copy and Past to run it.

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

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

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return new MaterialApp(
      title: 'Flutter Demo',
      theme: new ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: new MyHomePage(),
      debugShowCheckedModeBanner: false,
    );
  }
}

class MyHomePage extends StatefulWidget {
  @override
  _MyHomePageState createState() => new _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  String _swipeDirection = "";

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(),
      body: Center(
        child: Container(
          child: Row(
            children: <Widget>[
              Expanded(
                child: SwipeDetector(
                  child: Card(
                    child: Container(
                      padding: EdgeInsets.only(
                        top: 80.0,
                        bottom: 80.0,
                        left: 16.0,
                        right: 16.0,
                      ),
                      child: Column(
                        mainAxisSize: MainAxisSize.min,
                        children: <Widget>[
                          Text(
                            'Swipe Me!',
                            style: TextStyle(
                              fontSize: 40.0,
                            ),
                          ),
                          Text(
                            '$_swipeDirection',
                            style: TextStyle(),
                          ),
                        ],
                      ),
                    ),
                  ),
                  onSwipeUp: () {
                    setState(() {
                      _swipeDirection = "Swipe Up";
                    });
                  },
                  onSwipeDown: () {
                    setState(() {
                      _swipeDirection = "Swipe Down";
                    });
                  },
                  onSwipeLeft: () {
                    setState(() {
                      _swipeDirection = "Swipe Left";
                    });
                  },
                  onSwipeRight: () {
                    setState(() {
                      _swipeDirection = "Swipe Right";
                    });
                  },
                  swipeConfiguration: SwipeConfiguration(
                      verticalSwipeMinVelocity: 100.0,
                      verticalSwipeMinDisplacement: 50.0,
                      verticalSwipeMaxWidthThreshold:100.0,
                      horizontalSwipeMaxHeightThreshold: 50.0,
                      horizontalSwipeMinDisplacement:50.0,
                      horizontalSwipeMinVelocity: 200.0),
                ),
              )
            ],
          ),
        ),
      ),
    );
  }
}