You can use the setSize method of the Signin button to update the size.
For example, in my activity onCreate method:
mSignInButton = (SignInButton) findViewById(R.id.sign_in_button); mSignInButton.setOnClickListener(this); mSignInButton.setSize(SignInButton.SIZE_WIDE);
The login button will change.
You can also simply use the ANY button, which is properly branded simply by using the A button, and then using this operation as a button click handler.
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