Android Facebook 4.0 SDK How to get Email, Date of Birth and gender of User

That’s not the right way to set the permissions as you are overwriting them with each method call.

Replace this:

mButtonLogin.setReadPermissions("user_friends");
mButtonLogin.setReadPermissions("public_profile");
mButtonLogin.setReadPermissions("email");
mButtonLogin.setReadPermissions("user_birthday");

With the following, as the method setReadPermissions() accepts an ArrayList:

loginButton.setReadPermissions(Arrays.asList(
        "public_profile", "email", "user_birthday", "user_friends"));

Also here is how to query extra data GraphRequest:

private LoginButton loginButton;
private CallbackManager callbackManager;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_login);

    loginButton = (LoginButton) findViewById(R.id.login_button);

    loginButton.setReadPermissions(Arrays.asList(
            "public_profile", "email", "user_birthday", "user_friends"));

    callbackManager = CallbackManager.Factory.create();

    // Callback registration
    loginButton.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
        @Override
        public void onSuccess(LoginResult loginResult) {
            // App code
            GraphRequest request = GraphRequest.newMeRequest(
                    loginResult.getAccessToken(),
                    new GraphRequest.GraphJSONObjectCallback() {
                        @Override
                        public void onCompleted(JSONObject object, GraphResponse response) {
                            Log.v("LoginActivity", response.toString());

                            // Application code
                            String email = object.getString("email");
                            String birthday = object.getString("birthday"); // 01/31/1980 format
                        }
                    });
            Bundle parameters = new Bundle();
            parameters.putString("fields", "id,name,email,gender,birthday");
            request.setParameters(parameters);
            request.executeAsync();


        }

        @Override
        public void onCancel() {
            // App code
            Log.v("LoginActivity", "cancel");
        }

        @Override
        public void onError(FacebookException exception) {
            // App code
            Log.v("LoginActivity", exception.getCause().toString());
        }
    });
}

EDIT:

One possible problem is that Facebook assumes that your email is invalid. To test it, use the Graph API Explorer and try to get it. If even there you can’t get your email, change it in your profile settings and try again. This approach resolved this issue for some developers commenting my answer.