react-native upload file using XMLHttpRequest

gistfile1.txt

  _upload() {
    var xhr = new XMLHttpRequest();
    xhr.open('POST', 'http://posttestserver.com/post.php');
    xhr.onload = () => {
      this.setState({isUploading: false});
      if (xhr.status !== 200) {
        AlertIOS.alert(
          'Upload failed',
          'Expected HTTP 200 OK response, got ' + xhr.status
        );
        return;
      }
      if (!xhr.responseText) {
        AlertIOS.alert(
          'Upload failed',
          'No response payload.'
        );
        return;
      }
      var index = xhr.responseText.indexOf('http://www.posttestserver.com/');
      if (index === -1) {
        AlertIOS.alert(
          'Upload failed',
          'Invalid response payload.'
        );
        return;
      }
      var url = xhr.responseText.slice(index).split('\n')[0];
      LinkingIOS.openURL(url);
    };
    var formdata = new FormData();
    if (this.state.randomPhoto) {
      formdata.append('image', {...this.state.randomPhoto, name: 'image.jpg'});
    }
    this.state.textParams.forEach(
      (param) => formdata.append(param.name, param.value)
    );
    xhr.send(formdata);
    this.setState({isUploading: true});
  }
  
  
  
  
   _fetchRandomPhoto() {
    CameraRoll.getPhotos(
      {first: PAGE_SIZE},
      (data) => {
        console.log('isMounted', this._isMounted);
        if (!this._isMounted) {
          return;
        }
        var edges = data.edges;
        var edge = edges[Math.floor(Math.random() * edges.length)];
        var randomPhoto = edge && edge.node && edge.node.image;
        if (randomPhoto) {
          this.setState({randomPhoto});
        }
      },
      (error) => undefined
    );
  }