UIButton to capture image not responding - ios

Question

I am new to iOS development and I am trying to follow the following tutorial to learn how to capture images and then save them on a server for my purposes:
https://medium.com/#rizwanm/swift-camera-part-2-c6de440a9404
The tutorial is great and I am only initializing the camera and trying to snap the image (not doing the QR part).
Unfortunately, when I hit the 'capture' button, the image is not being taken or saved in my gallery and I am not able to understand why. I use Xcode 8.3 and I am running iOS 10.3 on my iPhone.
I have connected the button with the view controller and called it in the function onTapTakePhoto as shown in the code below. Please advise as to why this might be happening.
import UIKit
import AVFoundation
class ViewController: UIViewController {
#IBOutlet weak var previewView: UIView!
#IBOutlet weak var CaptureButton: UIButton!
//helps transfer data between one or more input device like camera
var captureSession: AVCaptureSession?
//instance variable
var capturePhotoOutput: AVCapturePhotoOutput? //capturePhotoOutput will help us snap a live photo
//helps render the camera view finder in ViewController
var videoPreviewLayer: AVCaptureVideoPreviewLayer?
override func viewDidLoad() {
super.viewDidLoad()
CaptureButton.layer.cornerRadius = CaptureButton.frame.size.width / 2
CaptureButton.clipsToBounds = true
//set up camera here
let captureDevice = AVCaptureDevice.defaultDevice(withMediaType: AVMediaTypeVideo)
// get an instance of the AVCAptureDevicenput
// serves as a middle man to attach input device to capture device
// chance the input device unavailable so wrap in do catch
do {
// Get an instance of the AVCaptureDeviceInput class using the previous deivce object
let input = try AVCaptureDeviceInput(device: captureDevice)
// Initialize the captureSession object
captureSession = AVCaptureSession()
// Set the input devcie on the capture session
captureSession?.addInput(input)
//set up preview view to see live feed
videoPreviewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
videoPreviewLayer?.videoGravity = AVLayerVideoGravityResizeAspectFill
videoPreviewLayer?.frame = view.layer.bounds
previewView.layer.addSublayer(videoPreviewLayer!)
// finally start the capture session
captureSession?.startRunning()
// get an instance of AVCapturePhotoOutput class
capturePhotoOutput = AVCapturePhotoOutput()
capturePhotoOutput?.isHighResolutionCaptureEnabled = true
//set the outut on the capture session
captureSession?.addOutput(capturePhotoOutput)
} catch {
print (error)
return
}
}
#IBAction func onTapTakePhoto(_ sender: UIButton) {
// Make sure capturePhotoOutput is valid
guard let capturePhotoOutput = self.capturePhotoOutput else { return }
// Get an instance of AVCapturePhotoSettings class
let photoSettings = AVCapturePhotoSettings()
// Set photo settings for our need
photoSettings.isAutoStillImageStabilizationEnabled = true
photoSettings.isHighResolutionPhotoEnabled = true
photoSettings.flashMode = .auto
// Call capturePhoto method by passing our photo settings and a delegate implementing AVCapturePhotoCaptureDelegate
capturePhotoOutput.capturePhoto(with: photoSettings, delegate: self)
}
}
// to get the captured image
extension ViewController : AVCapturePhotoCaptureDelegate {
func capture(_ captureOutput: AVCapturePhotoOutput,
didFinishProcessingPhotoSampleBuffer photoSampleBuffer: CMSampleBuffer?,
previewPhotoSampleBuffer: CMSampleBuffer?,
resolvedSettings: AVCaptureResolvedPhotoSettings,
bracketSettings: AVCaptureBracketedStillImageSettings?,
error: Error?) {
// Make sure we get some photo sample buffer
guard error == nil,
let photoSampleBuffer = photoSampleBuffer else {
print("Error capturing photo: \(String(describing: error))")
return
}
// Convert photo same buffer to a jpeg image data by using AVCapturePhotoOutput
guard let imageData = AVCapturePhotoOutput.jpegPhotoDataRepresentation(forJPEGSampleBuffer: photoSampleBuffer, previewPhotoSampleBuffer: previewPhotoSampleBuffer) else {
return
}
// Initialise an UIImage with our image data
let capturedImage = UIImage.init(data: imageData , scale: 1.0)
if let image = capturedImage {
// Save our captured image to photos album
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil)
}
}
}

Answer 1

One thing that you should check is that, if you have added the permission in the info.plist file to access the camera.
You have to make a key-value entry for the key
Privacy - Photo Library Usage Description
(if you are using the gallery)
and
Privacy - Camera Usage Description
for using the camera itself.
Refer to this for more details.
If it doesn't work, put a debugger on the click action of the button and check the code flow. If the debugger is not hit after pressing the button, there could be an issue with the button action outlet, try to remake the outlet action.

Answer 2

First of all with the help of break points, check which section of your code is not being executed.There might be some problem related to your button connection.
OR
Try this one
https://www.youtube.com/watch?v=994Hsi1zs6Q
OR
this one in Objective-C
https://github.com/omergul/LLSimpleCamera

Answer 3

Thank you for the answers :)
The problem was a missing connection to my action button code from the story board. Feels like such a silly mistake in retrospect

Answer 4

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
if (info[UIImagePickerControllerOriginalImage] as? UIImage) != nil {
}
dismiss(animated: true, completion:
{
// write your set image code for UIButton is here.
})
}