BLE.scan seems to never complete

Ionic Framework ionic-v3
1

I am a complete beginner at ionic 2, and am starting to develop an app using BLE. My app now picks up other BLE devices, but the completion function never seems to run, making the scan run forever it seems.

Here is my code:
``

scanFordevices() {
   let newDevices: Array<Device> = [];
   BLE.scan([], 5).subscribe(
        bleDevice => {
          console.log('Found device: ' + JSON.stringify(bleDevice));
          newDevices.push(device);
        },
        err => {
          console.log('Error when scanning for devices: ' + err);
        },
        () => {

          for (let device of newDevices) {
            console.log'Found device in newDevices: ' + JSON.stringify(device));
          }
          console.log('\nNo more devices: ');
        }
 	);
  };

``

I’d be very thankful for any help and advice. As I said I am a complete novice to ionic.