react-native-camera/README.md

# react-native-camera

A camera module for React Native.

![](https://i.imgur.com/5j2JdUk.gif)

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

- Orientation is not set correctly upon device rotation
- Stills captured to disk will not be cleaned up and thus must be managed manually for now

## Getting started

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'). Look for `Header Search Paths` and make sure it contains both `$(SRCROOT)/../react-native/React` and `$(SRCROOT)/../../React` - mark both as `recursive`.
5. Run your project (`Cmd+R`)

## Usage

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

```javascript
var React = require('react-native');
var {
  AppRegistry,
  StyleSheet,
  Text,
  View,
  TouchableHighlight
} = React;
var Camera = require('react-native-camera');

var cameraApp = React.createClass({
  getInitialState() {
    return {
      cameraType: Camera.constants.Camera.back
    }
  },

  render() {

    return (
      <Camera
        ref="cam"
        style={styles.container}
        onBarCodeRead={this._onBarCodeRead}
        type={this.state.cameraType}
      >
        <Text style={styles.welcome}>
          Welcome to React Native!
        </Text>
        <Text style={styles.instructions}>
          To get started, edit index.ios.js{'\n'}
          Press Cmd+R to reload
        </Text>
        <View>
          {preview}
        </View>
        <TouchableHighlight onPress={this._switchCamera}>
          <Text>The old switcheroo</Text>
        </TouchableHighlight>
        <TouchableHighlight onPress={this._takePicture}>
          <Text>Take Picture</Text>
        </TouchableHighlight>
      </Camera>
    );
  },
  _onBarCodeRead(e) {
    console.log(e);
  },
  _switchCamera() {
    var state = this.state;
    state.cameraType = state.cameraType === Camera.constants.Camera.back
      ? Camera.constants.Camera.front : Camera.constants.Camera.back;
    this.setState(state);
  },
  _takePicture() {
    var that = this;
    this.refs.cam.capture(function(err, data) {
      console.log(err, data);
    });
  }
});

AppRegistry.registerComponent('cameraApp', () => cameraApp);
```

## 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.


#### `captureMode`

Values: `Camera.constants.CaptureMode.still` (default)

The type of capture that will be performed by the camera - either a still image or (hopefully soon, video).

#### `captureTarget`

Values: `Camera.constants.CaptureTarget.memory` (default), `Camera.constants.CaptureTarget.disk`

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.Camera.front` or `"front"`, `Camera.constants.Camera.back` or `"back"` (default)

Use the `type` property to specify which camera to use.


#### `orientation`

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

*TODO: Add support for an `Auto` value to automatically adjust for orientation changes.*

#### `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.)

*TODO: Only emit one event for each barcode scanned.*

## Component 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,] callback)`

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 -- in the future, this is not currently supported -- video. `captureTarget` allows you to specify how you want the data to be captured and sent back to you. The available `target`s are `Camera.constants.CaptureTarget.memory` and `Camera.constants.CaptureTarget.disk` - the latter has been shown to dramatically improve camera performance.

## 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.

## Todo
These are some features I think would be important/beneficial to have included with this module. Pull requests welcome!

- [ ] Video support
- [ ] Flash mode setting
- [ ] Automatic orientation adjustment
- [ ] Tap to focus
- [ ] Optional facial recognition (w/ ability to style box around face)

------------

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.