react-native-image-pan-zoom

Show Cases

Zoom while sliding

Intelligent zoom

Getting Started

Installation

npm i react-native-image-pan-zoom --save

Basic Usage

• Install react-native first

$ npm i react-native -g

• Initialization of a react-native project

$ react-native init myproject

• Then, edit myproject/index.ios.js, like this:

import React, { Component } from 'react';
import {
  AppRegistry,
  Image,
  Dimensions
} from 'react-native';

import ImageZoom from 'react-native-image-pan-zoom';

class ImageZoom extends React.Component {
    render: function() {
        return (
            <ImageZoom cropWidth={Dimensions.get('window').width}
                       cropHeight={Dimensions.get('window').height}
                       imageWidth={200}
                       imageHeight={200}>
                <Image style={{width:200, height:200}}
                       source={{uri:'http://v1.qzone.cc/avatar/201407/07/00/24/53b9782c444ca987.jpg!200x200.jpg'}}/>
            </ImageZoom>
        )
    }
}

AppRegistry.registerComponent('myproject', () => ImageZoom);

Document

Props	Type	Description	DefaultValue
cropWidth(required)	number	operating area width	100
cropHeight(required)	number	operating area height	100
imageWidth(required)	number	picture width	100
imageHeight(required)	number	picture height	100
onClick	()=>void	onClick	()=>{}
panToMove	boolean	allow to move picture with one finger	true
pinchToZoom	boolean	allow scale with two fingers	true
leaveStayTime	number	how many milliseconds after the finger presses to trigger onClick	100
leaveDistance	number	how many finger movement can also trigger onClick	10
horizontalOuterRangeOffset	(offsetX?: number)=>void	horizontal beyond the distance, the parent to do picture switching, you can listen to this function. When this function is triggered, you can do the switch operation	()=>{}
onDragLeft	()=>void	trigger to switch to the left of the graph, the left sliding speed exceeds the threshold when triggered	()=>{}
responderRelease	(vx: number)=>void	let go but do not cancel	()=>{}
maxOverflow	number	maximum sliding threshold	100
longPressTime	number	long press threshold	800
onLongPress	()=>void	on longPress	()=> {}
doubleClickInterval	number	time allocated for second click to be considered as doublClick event	175
onMove	(object)=>void	reports movement position data (helpful to build overlays)	()=> {}
centerOn	{ x: number, y: number, scale: number, duration: number }	if given this will cause the map to pan and zoom to the desired location	undefined

Debug in this project

Make sure you had installed react-native with -g before.

git clone https://github.com/ascoders/react-native-image-zoom.git
cd react-native-image-zoom/demo
npm install
npm start

Then, scan the QR, use your expo app.