Ionic 3 subir archivo a servidor con native file transfer

import { Component } from '@angular/core';
import { NavController, NavParams } from 'ionic-angular';
import { FileTransfer, FileUploadOptions, FileTransferObject } from '@ionic-native/file-transfer';
import { Camera, CameraOptions } from '@ionic-native/camera';

@Component({
  selector: 'page-camera',
  templateUrl: 'camera.html',
})
export class CameraPage {

  _picture:string; // se almacena la URI de la imágen que proviene del plugin Camera

  constructor(public navCtrl: NavController,
              public navParams: NavParams,
              private camera: Camera,
              private transfer: FileTransfer) {

  }

  presentToast(message) {
    let toast = this.toastCtrl.create({
      message: message,
      duration: 3000,
      position: 'top'
    });

    toast.onDidDismiss(() => {
      console.log(message);
    });

    toast.present();
  }

  myFunction(){
    const fileTransfer: FileTransferObject = this.transfer.create();
    let apiUrl = 'http://www.miwebdefotos.com/api/subirimagen';

    let options: FileUploadOptions = {
       fileKey: 'file',
       fileName: 'name.jpg',
       headers: {}
    }

    fileTransfer.upload(this._picture, apiUrl, options)
     .then((data) => {
       // success
       //Mostrar mensaje que que ha sido subida con exito
        this.presentToast(data.response);
     }, (err) => {
       // error
       this.presentToast(err.message);
     })
  }

}