Google Sign-In for iOS - Create a custom sign-in button programmatically

The GIDSignInButton can be assigned as one of the following styles (See GIDSignInButton Class):

GIDSignInButtonStyle.Standard => 230x48

GIDSignInButtonStyle.Wide     => 312x48

GIDSignInButtonStyle.IconOnly =>  48x48

However, we may need custom styles other than the above sign-in buttons. For example the 48x48 IconOnly style is a bit small on the screen and hence we want to enlarge it. So the code below shows how to implement a custom Google sign-in button with these properties:

• Custom image
• Custom button size
• Circular shape

To get started, implement a standard Google Sign-In button with instructions in this tutorial:

Google Sign-In for iOS - Create a GIDSignInButton programmatically in Swift

Then remove the GIDSignInButton and add a UIButton instead:

    var btnSignIn : UIButton!

    

    override func viewDidLoad() {

        super.viewDidLoad()

        

        ...

        

        let btnSize : CGFloat = 100

        btnSignIn = UIButton(frame: CGRectMake(0,0,btnSize,btnSize))

        btnSignIn.center = view.center

        btnSignIn.setImage(UIImage(named: "google_logo.png"), forState: UIControlState.Normal)

        btnSignIn.addTarget(self, action: #selector(btnSignInPressed), forControlEvents: UIControlEvents.TouchUpInside)

        //Circular button

        btnSignIn.layer.cornerRadius = btnSize/2

        btnSignIn.layer.masksToBounds = true

        btnSignIn.layer.borderColor = UIColor.blackColor().CGColor

        btnSignIn.layer.borderWidth = 2

        view.addSubview(btnSignIn)

        ...

    }

    

    func btnSignInPressed() {

        GIDSignIn.sharedInstance().signIn()

    }

Result:

Related Information:

Facebook SDK and Swift - Create a custom login button programmatically