How I can build sign-in to play games without google normal sign-in button

Question

I've a question about google play games services.

My question is why I can't create sign-in to play games without google normal sign-in button ?

I played many games and those games has sign-in to play games without google normal sign-in button.

Do I should build google normal sign-in button before create sign-in play games button ?

Note : I mean about (google normal sign-in button) like below image because I dunno what's name that button.

Answer 1

It is not necessary to create google sign in button to sign-in to play games .

You can have the sign in code onClick of regular button or, onCreate() or onStart callback method of the activity

For example :

RegulerButton.setOnClickListener(new View.OnClickListener() {

   @Override

   public void onClick(View view) {

       startSignInIntent();

   }

});

Following link shows you the code for startSignInIntent() method https://developers.google.com/games/services/android/signin#performing_interactive_sign-in