FacebookSdk.sdkInitialize(getActivity().getApplicationContext());
[![enter image description here][1]][1]callbackManager = CallbackManager.Factory.create();
btn_signUp_with_fb.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
        @Override
        public void onSuccess(LoginResult loginResult) {

            System.out.println("onSuccess");
            String accessToken = loginResult.getAccessToken()
                    .getToken();
            Log.i("accessToken", accessToken+"");

            GraphRequest request = GraphRequest.newMeRequest(
                    loginResult.getAccessToken(),
                    new GraphRequest.GraphJSONObjectCallback() {
                        @Override
                        public void onCompleted(JSONObject object,
                                                GraphResponse response) {

                            Log.i("LoginActivity",
                                    response.toString());
                            id = object.optString("id");
                            try {
                                URL profile_pic = new URL(
                                        "http://graph.facebook.com/" + id + "/picture?type=large");
                                Log.i("profile_pic",
                                        profile_pic + "");

                            } catch (MalformedURLException e) {
                                e.printStackTrace();
                            }
                            String name = object.optString("name");
                            String email = object.optString("email");
                            String gender = object.optString("gender");
                            String first_name = object.optString("first_name");
                            String birthday = object.optString("birthday");

                            int  device_type = 0;
                            String login_type = "fb";
                            String social_login_api = Constants.BASE_URL + Constants.SOCIAL_URL + "username=" + first_name + "&password=" + id + "&device_type=" + device_type + "&device_token=" +Constants.device_id
                                    + "&email=" + email + "&login_type=" + login_type;
                            Log.e("social api", social_login_api);
                            helper = new WebAPIHelper(Constants.SOCIAL_LOGIN_API, SignUp_Fragment.this, true);
                            helper.callRequestGet(social_login_api);

                            SecurePreferences.savePreferences(getActivity(), "fb_email", email);
                            SecurePreferences.savePreferences(getActivity(), "fb_id", id);
                            SecurePreferences.savePreferences(getActivity(), "fb_name", name);
                            SecurePreferences.savePreferences(getActivity(), "fb_firstname", first_name);
                            SecurePreferences.savePreferences(getActivity(), "fb_lastname", birthday);
                        }
                    });
            Bundle parameters = new Bundle();
            parameters.putString("fields",
                    "id,name,email,gender,first_name,birthday");
            request.setParameters(parameters);
            request.executeAsync();
        }

        @Override
        public void onCancel() {
            Log.i("TAg", "cancelTriggered");
        }

        @Override
        public void onError(FacebookException error) {
            Log.i("TAg", "errorTriggered");
        }
    });



 txt_signUp_with_fb.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            if (v == txt_signUp_with_fb) {
                btn_signUp_with_fb.performClick();
            }
        }
    });