override func viewDidAppear(animated: Bool)
    {
        initView()
        _gridLines = false

    }

func initView()
    {
        _cameraFeed.initAfterLoad()
        //center the buttons on half distance between middle button and screen edge
        var middleDistance:CGFloat = _swapButton.frame.origin.x + _swapButton.frame.width/2
        _linesButton.frame.origin.x = middleDistance/2 - _linesButton.frame.width/2
        _flashButton.frame.origin.x = middleDistance + middleDistance/2 - _flashButton.frame.width/2
        _selectPhotos.frame.origin.x = middleDistance/2 - _selectPhotos.frame.width/2
    }