back por todo lado

func setupBackButton(){
        var count: Int? = navigationController?.viewControllers.count
        if count > 0 && navigationItem.leftBarButtonItem == nil{
            if  !(navigationController?.viewControllers.first === self) {
                self.navigationItem.leftBarButtonItem = HSAppearance.barButtonWithTitle("BACK", image:UIImage(named:"ArrowLeft"), target: self, action: "HSBackAction:")
            }
        }
    }
    
    
    el metodo para ese custom bar button:
    
    class func barButtonWithTitle(title: String?, image:UIImage?, target: AnyObject?, action: Selector, rightAlign:Bool=false) -> UIBarButtonItem{
        var titleColor:UIColor! = UIColor.whiteColor()
        var but: UIButton = UIButton.buttonWithType(UIButtonType.Custom) as UIButton
        but.frame = CGRectMake(0, 0, 70, 30);
        but.backgroundColor = UIColor.clearColor()
        but.setImage(image, forState: UIControlState.Normal)
        but.titleEdgeInsets = UIEdgeInsetsMake(0, 4, 0, 0)
        but.titleLabel?.font = UIFont(name: CustomFont.CuprumRegular.rawValue, size: 15)
        but.setTitleColor(titleColor, forState: UIControlState.Normal)
        but.setTitle(title, forState: UIControlState.Normal)
        but.addTarget(target, action: action, forControlEvents: UIControlEvents.TouchUpInside)
        but.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Left
        if rightAlign {
            but.contentHorizontalAlignment = UIControlContentHorizontalAlignment.Right
            but.imageEdgeInsets = UIEdgeInsetsMake(0, but.frame.size.width - but.imageView!.width, 0, 0)
            but.titleEdgeInsets = UIEdgeInsetsMake(0, 0, 0, but.imageView!.width + 4)
        }
//        but.sizeToFit()
        
        var barButton = UIBarButtonItem(customView: but)
        
        return barButton
    }