Facebook SDK 4.0.1 Login without login button

Question

I\'m trying to log in without using login button. I followed facebook tutorial but i can not get it work, always give me NullPointerException. My Manifest:

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Answer 1

Try in this way:

• Create Android app on Facebook developer and set it to public instead development mode.

• Manifest:

• Strings.xml

  XXXXXXXXXXXXXX

• If you want to use fragment for Login the proper way is:

Step 1:

    CallbackManager mCallbackManager;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //@Deprecated for latest version, without this line working fine. 
        //FacebookSdk.sdkInitialize(getActivity().getApplicationContext());


        mCallbackManager = CallbackManager.Factory.create();

        LoginManager.getInstance().registerCallback(mCallbackManager,
            new FacebookCallback() {
                @Override
                public void onSuccess(LoginResult loginResult) {
                    // App code
                    Log.e("Success", "Login");
                    Bundle parameters = new Bundle();
                    parameters.putString("fields", "id, first_name, last_name ,email, gender, birthday");

                    GraphRequest gr = GraphRequest.newMeRequest(
                            loginResult.getAccessToken(), new GraphRequest.GraphJSONObjectCallback() {
                                @Override
                                public void onCompleted(JSONObject json, GraphResponse response) {
                                    if (response.getError() != null) {
                                        // handle error
                                        System.out.println("ERROR "+response.getError().toString());
                                    } else {
                                        //System.out.println("Success");
                                        try {

                                            String jsonresult = String.valueOf(json);
                                            System.out.println("JSON Result"+jsonresult);
                                            String resp = String.valueOf(response.getJSONObject());
                                            System.out.println("JSON resp "+resp);


                                        } catch (JSONException e) {
                                            e.printStackTrace();
                                        }
                                    }
                                }

                            });
                    gr.setParameters(parameters);
                    gr.executeAsync();

                }

                @Override
                public void onCancel() {
                    // App code
                    Log.e("onCancel", "Login");
                }

                @Override
                public void onError(FacebookException onError) {
                    // App code
                    Log.e("onError", "Login "+onError.getMessage());
                }
            });
    }

Step 2:

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == Activity.RESULT_OK) {
            mCallbackManager.onActivityResult(requestCode, resultCode, data);
        }
    }

Step 3: - inside OnClickListener

LoginManager.getInstance().logInWithReadPermissions(YourFragment.this, Arrays.asList("public_profile"));

I was using getActivity() and because of this every time something flashes instead showing Facebook Login view. Basically instead getActivity() have to use FragmentClaseName.this. I hope this will help u. Happy coding!!!