title: Using react-native-camera, how to access saved pictures?
body: <p>My goal is to use the react-native-camera and simply show a picture on the same screen, if a picture has been taken. I'm trying to save the picture source as "imageURI". If it exists, I want to show it, if a picture hasn't been taken yet, just show text saying No Image Yet. I've got the camera working, since I can trace the app is saving pictures to the disk. Having trouble with the following: </p>
  
  <ul>
  <li>How to assign the capture functions data to a variable when I take the picture, that I can call later (imageURI).</li>
  <li><p>Don't know how to do an if statement in Javascript to check if a variable exists yet.</p>
  
  <pre><code>import Camera from 'react-native-camera';
  
  export default class camerahere extends Component {
  
  _takePicture () {
    this.camera.capture((err, data) =&gt; {
    if (err) return;
    imageURI = data;
    });
  }
  
  render() {
  
    if ( typeof imageURI == undefined) {
      image = &lt;Text&gt; No Image Yet &lt;/Text&gt; 
    } else {
      image = &lt;Image source={{uri: imageURI, isStatic:true}} 
      style={{width: 100, height: 100}} /&gt;
    }
  
  
  return (
    &lt;View style={styles.container}&gt;
      &lt;Camera
        captureTarget={Camera.constants.CaptureTarget.disk}
        ref={(cam) =&gt; {
          this.camera = cam;
        }}
        style={styles.preview}
        aspect={Camera.constants.Aspect.fill}&gt;
  
        {button}
      &lt;TouchableHighlight onPress={this._takePicture.bind(this)}&gt;
        &lt;View style={{height:50,width:50,backgroundColor:"pink"}}&gt;&lt;/View&gt;
  &lt;/TouchableHighlight&gt;
  &lt;/Camera&gt;
  </code></pre>
  
  <p></p></li>
  </ul>