jiaoxuebing2014 / react-native-camera

A Camera component for React Native. Also supports barcode scanning!

react-native-camera

A camera module for React Native.

Known Issues

Below is a list of known issues. Pull requests are welcome for any of these issues!

• Stills captured to disk will not be cleaned up and thus must be managed manually for now

Getting started

Mostly automatic install

1. npm install rnpm --global
2. npm install react-native-camera@latest --save
3. rnpm link react-native-camera

Manual install

iOS

1. npm install react-native-camera@latest --save
2. In XCode, in the project navigator, right click Libraries ➜ Add Files to [your project's name]
3. Go to node_modules ➜ react-native-camera and add RCTCamera.xcodeproj
4. In XCode, in the project navigator, select your project. Add libRCTCamera.a to your project's Build Phases ➜ Link Binary With Libraries
5. Click RCTCamera.xcodeproj in the project navigator and go the Build Settings tab. Make sure 'All' is toggled on (instead of 'Basic'). In the Search Paths section, look for Header Search Paths and make sure it contains both $(SRCROOT)/../../react-native/React and $(SRCROOT)/../../../React - mark both as recursive.
6. Run your project (Cmd+R)

Android

1. npm install react-native-camera@latest --save
2. Open up `android/app/main/java/[...]/MainActivity.java

• Add import com.lwansbrough.RCTCamera.*; to the imports at the top of the file
• Add new RCTCameraPackage() to the list returned by the getPackages() method

3. Append the following lines to android/settings.gradle:

   include ':react-native-camera'
   project(':react-native-camera').projectDir = new File(rootProject.projectDir, 	'../node_modules/react-native-camera/android')
   

4. Insert the following lines inside the dependencies block in android/app/build.gradle:

   compile project(':react-native-camera')
   

Usage

All you need is to require the react-native-camera module and then use the <Camera/> tag.

'use strict';
import React, {
  AppRegistry,
  Component,
  Dimensions,
  StyleSheet,
  Text,
  TouchableHighlight,
  View
} from 'react-native';
import Camera from 'react-native-camera';

class BadInstagramCloneApp extends Component {
  render() {
    return (
      <View style={styles.container}>
        <Camera
          ref={(cam) => {
            this.camera = cam;
          }}
          style={styles.preview}
          aspect={Camera.constants.Aspect.Fill}>
          <Text style={styles.capture} onPress={this.takePicture.bind(this)}>[CAPTURE]</Text>
        </Camera>
      </View>
    );
  }
  
  takePicture() {
    this.camera.capture()
      .then((data) => console.log(data))
      .catch(err => console.error(err));
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1
  },
  preview: {
    flex: 1,
    justifyContent: 'flex-end',
    alignItems: 'center',
    height: Dimensions.get('window').height,
    width: Dimensions.get('window').width
  },
  capture: {
    flex: 0,
    backgroundColor: '#fff',
    borderRadius: 5,
    color: '#000',
    padding: 10,
    margin: 40
  }
});

AppRegistry.registerComponent('BadInstagramCloneApp', () => BadInstagramCloneApp);

Properties

aspect

Values: Camera.constants.Aspect.fit or "fit", Camera.constants.Aspect.fill or "fill" (default), Camera.constants.Aspect.stretch or "stretch"

The aspect property allows you to define how your viewfinder renders the camera's view. For instance, if you have a square viewfinder and you want to fill the it entirely, you have two options: "fill", where the aspect ratio of the camera's view is preserved by cropping the view or "stretch", where the aspect ratio is skewed in order to fit the entire image inside the viewfinder. The other option is "fit", which ensures the camera's entire view fits inside your viewfinder without altering the aspect ratio.

iOS captureAudio

Values: true (default), false (Boolean)

Applies to video capture mode only. Specifies whether or not audio should be captured with the video.

iOS captureMode

Values: Camera.constants.CaptureMode.still (default), Camera.constants.CaptureMode.video

The type of capture that will be performed by the camera - either a still image or video.

captureTarget

Values: Camera.constants.CaptureTarget.cameraRoll (default), Camera.constants.CaptureTarget.disk, Camera.constants.CaptureTarget.temp, Camera.constants.CaptureTarget.memory (deprecated),

This property allows you to specify the target output of the captured image data. By default the image binary is sent back as a base 64 encoded string. The disk output has been shown to improve capture response time, so that is the recommended value.

type

Values: Camera.constants.Type.front or "front", Camera.constants.Type.back or "back" (default)

Use the type property to specify which camera to use.

orientation

Values: Camera.constants.Orientation.auto or "auto" (default), Camera.constants.Orientation.landscapeLeft or "landscapeLeft", Camera.constants.Orientation.landscapeRight or "landscapeRight", Camera.constants.Orientation.portrait or "portrait", Camera.constants.Orientation.portraitUpsideDown or "portraitUpsideDown"

The orientation property allows you to specify the current orientation of the phone to ensure the viewfinder is "the right way up."

iOS onBarCodeRead

Will call the specified method when a barcode is detected in the camera's view.

Event contains data (the data in the barcode) and bounds (the rectangle which outlines the barcode.)

The following barcode types can be recognised:

• aztec
• code138
• code39
• code39mod43
• code93
• ean13
• ean8
• pdf417
• qr
• upce
• datamatrix (when available)

The barcode type is provided in the data object.

flashMode

Values: Camera.constants.FlashMode.on, Camera.constants.FlashMode.off, Camera.constants.FlashMode.auto

Use the flashMode property to specify the camera flash mode.

torchMode

Values: Camera.constants.TorchMode.on, Camera.constants.TorchMode.off, Camera.constants.TorchMode.auto

Use the torchMode property to specify the camera torch mode.

onFocusChanged: Event { nativeEvent: { touchPoint: { x, y } }

Called when a touch focus gesture has been made. By default, onFocusChanged is not defined and tap-to-focus is disabled.

defaultOnFocusComponent

Values: true (default) false

If defaultOnFocusComponent set to false, default internal implementation of visual feedback for tap-to-focus gesture will be disabled.

onZoomChanged: Event { nativeEvent: { velocity, zoomFactor } }

Called when focus has changed. By default, onZoomChanged is not defined and pinch-to-zoom is disabled.

Component instance methods

You can access component methods by adding a ref (ie. ref="camera") prop to your <Camera> element, then you can use this.refs.camera.capture(cb), etc. inside your component.

capture([options]): Promise

Captures data from the camera. What is captured is based on the captureMode and captureTarget props. captureMode tells the camera whether you want a still image or video. captureTarget allows you to specify how you want the data to be captured and sent back to you. See captureTarget under Properties to see the available values. The promise will be fulfilled with the image data or file handle of the image on disk, depending on target.

Supported options:

• audio (See captureAudio under Properties)
• mode (See captureMode under Properties)
• target (See captureTarget under Properties)
• metadata This is metadata to be added to the captured image.
  • location This is the object returned from navigator.geolocation.getCurrentPosition() (React Native's geolocation polyfill). It will add GPS metadata to the image.
• rotation This will rotate the image by the number of degrees specified.

iOS getFOV(): Promise

Returns the camera's current field of view.

iOS hasFlash(): Promise

Returns whether or not the camera has flash capabilities.

stopCapture()

Ends the current capture session for video captures. Only applies when the current captureMode is video.

Component static methods

Camera.checkDeviceAuthorizationStatus(): Promise

Exposes the native API for checking if the device has authorized access to the camera. Can be used to call before loading the Camera component to ensure proper UX. The promise will be fulfilled with true or false depending on whether the device is authorized.

Subviews

This component supports subviews, so if you wish to use the camera view as a background or if you want to layout buttons/images/etc. inside the camera then you can do that.

---

Thanks to Brent Vatne (@brentvatne) for the react-native-video module which provided me with a great example of how to set up this module.