Detect existence of camera in iPhone app?

Question

I'm writing an iOS app, and I need to be able to detect if the device has a camera. Previously, I would check if the device is an iPhone or not, since only the iPhone has a camera - but with the launch of the iPod Touch 4 this is no longer a viable option. The app functions without a camera, but the presence of a camera adds functionality.

So, can anyone provide me with code that returns whether there is a camera or not?

Answer 1

You can use +isSourceTypeAvailable: method in UIImagePickerController:

if ([UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypeCamera])
   // Has camera

Answer 2

As Juan Boero wrote check the:

    if UIImagePickerController.isSourceTypeAvailable(.camera) {...}

But I would add another check to see if the user allowed access to camera as apple suggests in their PhotoPicker example ( PhotoPicker example Objective-C ):

* please note you have to import AVFoundation

SWIFT 5

    let authStatus = AVCaptureDevice.authorizationStatus(for: AVMediaType.video)
    switch authStatus {
        /*
         Status Restricted -
         The client is not authorized to access the hardware for the media type. The user cannot change the client's status, possibly due to active restrictions such as parental controls being in place.
         */
    case .denied, .restricted:
        // Denied access to camera
        // Explain that we need camera access and how to change it.
        let dialog = UIAlertController(title: "Unable to access the Camera", message: "To enable access, go to Settings > Privacy > Camera and turn on Camera access for this app.", preferredStyle: UIAlertController.Style.alert)

        let okAction = UIAlertAction(title: "OK", style: UIAlertAction.Style.default, handler: nil)

        dialog.addAction(okAction)
        self.present(dialog, animated:true, completion:nil)
    case .notDetermined:
        // The user has not yet been presented with the option to grant access to the camera hardware.
        // Ask for it.
        AVCaptureDevice.requestAccess(for: AVMediaType.video, completionHandler: { (grantd) in
        // If access was denied, we do not set the setup error message since access was just denied.
           if grantd {
           // Allowed access to camera, go ahead and present the UIImagePickerController.
            self.showImagePickerForSourceType(sourceType: UIImagePickerController.SourceType.camera)
            }
        })
    case .authorized:
        // Allowed access to camera, go ahead and present the UIImagePickerController.
        self.showImagePickerForSourceType(sourceType: UIImagePickerController.SourceType.camera)
    @unknown default:
        break; //handle other status
    }

SWIFT 3

let authStatus = AVCaptureDevice.authorizationStatus(forMediaType: AVMediaTypeVideo)
    
if authStatus == AVAuthorizationStatus.denied {
    // Denied access to camera
    // Explain that we need camera access and how to change it.
    let dialog = UIAlertController(title: "Unable to access the Camera", message: "To enable access, go to Settings > Privacy > Camera and turn on Camera access for this app.", preferredStyle: UIAlertControllerStyle.alert)
        
    let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil)
        
    dialog.addAction(okAction)
    self.present(dialog, animated:true, completion:nil)
        
} else if authStatus == AVAuthorizationStatus.notDetermined {     // The user has not yet been presented with the option to grant access to the camera hardware.
    // Ask for it.
    AVCaptureDevice.requestAccess(forMediaType: AVMediaTypeVideo, completionHandler: { (grantd) in
    // If access was denied, we do not set the setup error message since access was just denied.
       if grantd {
       // Allowed access to camera, go ahead and present the UIImagePickerController.
            self.showImagePickerForSourceType(sourceType: UIImagePickerControllerSourceType.camera)
        }
    })
} else {
        
    // Allowed access to camera, go ahead and present the UIImagePickerController.
    self.showImagePickerForSourceType(sourceType: UIImagePickerControllerSourceType.camera)

}

func showImagePickerForSourceType(sourceType: UIImagePickerControllerSourceType) {
    
    let myPickerController = UIImagePickerController()
    myPickerController.delegate = self;
    myPickerController.sourceType = sourceType  
    self.present(myPickerController, animated: true, completion: nil)
}

Answer 3

If you are using the AV Foundation classes instead of UIImagePickerController you can do:

BOOL hasCamera = ([[AVCaptureDevice devices] count] > 0);

If you are using UIImagePickerController it probably isn't worth it, since you'd have to add AVFoundation.framework to your project.

Answer 4

是的，提供了一个 API 来做到这一点：

BOOL isCamera = [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera];

Answer 5

Swift:

if UIImagePickerController.isSourceTypeAvailable(.Camera){

    //Your code goes here
    //For example you can print available media types:

    print(UIImagePickerController.availableMediaTypesForSourceType(.Camera))

    }

Answer 6

如果您需要知道设备是专门配备前置​​摄像头还是后置摄像头，请使用以下命令：

isCameraAvailable = [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront];

Answer 7

检查相机是否可用（Swift）

if(!UIImagePickerController.isSourceTypeAvailable(UIImagePickerControllerSourceType.Camera))

Answer 8

You can check for availability of a specific source type using discovery session (Swift 5):

let discovery = AVCaptureDevice.DiscoverySession.init(deviceTypes: [.builtInWideAngleCamera], mediaType: AVMediaType.video, position: .back)
let isWideAngleCameraSupported = !discovery.devices.isEmpty