如何更改FBSDKLoginButton iOS 8.3 / Swift 1.2的默认设计？

Question

我目前正在开发App，我需要更改Facebook
SDK提供的Facebook按钮的默认设计。我成功地使提供的按钮透明，并将其粘贴在设计视图上方，并且效果很好（现在设计已经匹配，Facebook
SDK按钮的功能也很好）。我这样做之后出现了问题，因为按钮丢失了它的Ui效果（单击时未突出显示）。如果有人可以帮助我，请给此设计的按钮添加突出显示效果。让我们澄清一下：我已经将UIView设计为按钮，在其上面放置了一个透明的Facebook
SDK按钮，结果是我的设计形状和Facebook按钮的功能同时出现，但失​​去了：单击时没有突出显示效果。

Answer 1

我尝试了以下代码，它以正确的方式提供了功能。但是，单击按钮后，我未能给按钮赋予突出显示效果。这是代码：

{
    if (FBSDKAccessToken.currentAccessToken() != nil)
        {
            // if user logged in then handleTap func will run instead of button functionality
            let tap = UITapGestureRecognizer(target: self, action: "handleTap:")
            self.btnSignUpwithFaceBook.addGestureRecognizer(tap)

        }

        else
        {
            let loginView : FBSDKLoginButton = FBSDKLoginButton()
            self.view.addSubview(loginView)
            loginView.center = self.btnSignUpwithFaceBook.center
            loginView.frame.size.width = self.btnSignUpwithFaceBook.frame.width
            loginView.frame.size.height = self.btnSignUpwithFaceBook.frame.height
            loginView.frame.origin.x = self.btnSignUpwithFaceBook.frame.origin.x
            loginView.frame.origin.y = self.btnSignUpwithFaceBook.frame.origin.y

            for subView in loginView.subviews
            {
                subView.removeFromSuperview()
            }
            loginView.layer.shadowColor = UIColor.clearColor().CGColor

            loginView.setBackgroundImage(nil, forState: UIControlState.Normal)
            loginView.setBackgroundImage(nil, forState: UIControlState.Application)
            loginView.setBackgroundImage(nil, forState: UIControlState.allZeros)
            loginView.setBackgroundImage(nil, forState: UIControlState.Highlighted)
            loginView.setBackgroundImage(nil, forState: UIControlState.Reserved)
            loginView.setBackgroundImage(nil, forState: UIControlState.Selected)

            loginView.setImage(nil, forState: UIControlState.Normal)
            loginView.setImage(nil, forState: UIControlState.Application)
            loginView.setImage(nil, forState: UIControlState.allZeros)
            loginView.setImage(nil, forState: UIControlState.Highlighted)
            loginView.setImage(nil, forState: UIControlState.Reserved)
            loginView.setImage(nil, forState: UIControlState.Selected)

            loginView.backgroundColor = UIColor.clearColor()
            // just for test
            self.btnSignUpwithFaceBook.layer.borderWidth = 1
            self.btnSignUpwithFaceBook.layer.borderColor = UIColor.whiteColor().CGColor
            loginView.layer.backgroundColor = UIColor.clearColor().CGColor

            loginView.readPermissions = ["public_profile", "email", "user_friends"]
            loginView.delegate = self
            loginView.setTranslatesAutoresizingMaskIntoConstraints(false)

            var constX = NSLayoutConstraint(item: loginView, attribute: NSLayoutAttribute.CenterX, relatedBy: NSLayoutRelation.Equal, toItem: self.btnSignUpwithFaceBook, attribute: NSLayoutAttribute.CenterX, multiplier: 1, constant: 0)
            view.addConstraint(constX)

            var constY = NSLayoutConstraint(item: loginView, attribute: NSLayoutAttribute.CenterY, relatedBy: NSLayoutRelation.Equal, toItem: self.btnSignUpwithFaceBook, attribute: NSLayoutAttribute.CenterY, multiplier: 1, constant: 0)
            view.addConstraint(constY)

            let views = ["loginView": loginView]

            var constH = NSLayoutConstraint.constraintsWithVisualFormat("H:[loginView(57)]", options: NSLayoutFormatOptions(0), metrics: nil, views: views)
            view.addConstraints(constH)


            var constW = NSLayoutConstraint.constraintsWithVisualFormat("V:[loginView(281)]", options: NSLayoutFormatOptions(0), metrics: nil, views: views)

            view.addConstraints(constW)

}

实际上，主要问题是facebookLogInButton是FBSDK的自定义类，而swift并不将其视为uiButton，这就是为什么没有突出显示属性的原因。因此，我希望您的帮助人员能够找到它的要点是找到一种方法，使facebookLoginButton迅速被视为uiButton。