How to call the UIImagePickerControllerSourceTypeCamera continuously

I have the following problem when developing on iOS. I want to achieve that when I'm clicking on a tabbar item the camera shows up. Now that isn't so hard but the problem is this happens once. So when I click on another tabbar item and click back to the camera item, the camera doesn't show up again.

I think this is because when you click on cancel the UIImagePickerController dismisses and doesn't initialize again. How can I solve this problem, that when I'm clicking on the tabbar item the camara will always show up.

class CameraViewController: UIViewController, UIImagePickerControllerDelegate,UINavigationControllerDelegate {

@IBOutlet weak var imageView: UIImageView!
let imagePicker:UIImagePickerController!

override func viewDidLoad() {
    super.viewDidLoad();
    self.loadCamera();
}


func loadCamera(){

        if UIImagePickerController.isSourceTypeAvailable(
            UIImagePickerControllerSourceType.Camera) {

                imagePicker = UIImagePickerController();
                imagePicker.delegate = self;
                imagePicker.sourceType = .Camera;

                presentViewController(imagePicker, animated: true, completion: nil)

        }
    }

    func imagePickerController(picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [NSObject : AnyObject]) {
        imagePicker.dismissViewControllerAnimated(true, completion: nil)
        imageView.image = info[UIImagePickerControllerOriginalImage] as? UIImage


    }


}