我刚刚了解了 facebook SDK on android。我已经在 stackoverflow 和 facebook developer guide 上搜索登录，但是当从 facebook sdk 获取个人资料数据时我仍然卡住了。我尝试从以下位置实现解决方案:unable get profile和 Get email ，但仍然卡住了。

这是我的代码:

    public class HomeLoginActivity extends Activity {
   LoginButton btnFacebook;
    CallbackManager callbackManager = CallbackManager.Factory.create();
    ProfileTracker profTrack;
    AccessTokenTracker accessTokenTracker;
    TextView welcomeText;
    FacebookCallback<LoginResult> mFacebookCallback;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        FacebookSdk.sdkInitialize(this.getApplicationContext());
        setContentView(R.layout.activity_home_login);
        welcomeText = (TextView) findViewById(R.id.welcome_id);
        accessTokenTracker = new AccessTokenTracker() {
            @Override
            protected void onCurrentAccessTokenChanged(
                    AccessToken oldAccessToken,
                    AccessToken currentAccessToken) {
                // App code
                Log.d("current token", "" + currentAccessToken);

                //}
            }
        };
        profTrack = new ProfileTracker() {
            @Override
            protected void onCurrentProfileChanged(
                    Profile oldProfile,
                    Profile currentProfile) {
                // App code
                Log.d("current profile", "" + currentProfile);
                welcomeText.setText(constructWelcomeMessage(currentProfile));
            }

        };
        mFacebookCallback = new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {
                AccessToken accessToken = loginResult.getAccessToken();
                Profile profile = Profile.getCurrentProfile();
                welcomeText.setText(constructWelcomeMessage(profile));

                GraphRequest request = GraphRequest.newMeRequest(
                        loginResult.getAccessToken(),
                        new GraphRequest.GraphJSONObjectCallback() {
                            @Override
                            public void onCompleted(
                                    JSONObject object,
                                    GraphResponse response) {
                                // Application code
                                try {
                                    String id=object.getString("id");
                                    String name=object.getString("name");
                                    String email=object.getString("email");
                                    String gender=object.getString("gender");
                                    Stringbirthday=object.getString("birthday");

                                    //do something with the data here
                                } catch (JSONException e) {
                                    e.printStackTrace(); 
                                }
                            }
                        });
                Bundle parameters = new Bundle();
                parameters.putString("fields", "id,name,email,gender,birthday");
                request.setParameters(parameters);
                request.executeAsync();
            }

            @Override
            public void onCancel() {

            }

            @Override
            public void onError(FacebookException e) {

            }
        };

        accessTokenTracker.startTracking();
        profTrack.startTracking();

        //Button Facebook
        btnFacebook = (LoginButton) findViewById(R.id.btnFacebook);
        btnFacebook.setReadPermissions("public_profile", "user_friends");
        btnFacebook.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            LoginManager.getInstance().logInWithReadPermissions((Activity) v.getContext(),Arrays.asList("public_profile", "user_friends"));
            }
        });
        btnFacebook.registerCallback(callbackManager, mFacebookCallback);

    }
    // ennd on create
    private String constructWelcomeMessage(Profile profile) {
        StringBuffer stringBuffer = new StringBuffer();
        if (profile != null) {
            stringBuffer.append("Welcome " + profile.getName());
        }
        else {
            stringBuffer.append("NULL Profile");
        }
        return stringBuffer.toString();
    }


    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        callbackManager.onActivityResult(requestCode, resultCode, data);

    }
    @Override
    public void onResume() {
        super.onResume();
        AccessToken.getCurrentAccessToken();
        Log.d("resume current token", "" + AccessToken.getCurrentAccessToken());
        Profile.fetchProfileForCurrentAccessToken();
    }

    @Override
    public void onStop() {
        super.onStop();
        profTrack.stopTracking();
        accessTokenTracker.stopTracking();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        accessTokenTracker.stopTracking();
        profTrack.stopTracking();
    }
}

还有我的日志猫:

 java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.getString(java.lang.String)' on a null object reference
            at com.twiscode.gimme.HomeLoginActivity$3$1.onCompleted(HomeLoginActivity.java:100)
            at com.facebook.GraphRequest$1.onCompleted(GraphRequest.java:298)
            at com.facebook.GraphRequest$5.run(GraphRequest.java:1246)
            at android.os.Handler.handleCallback(Handler.java:739)
            at android.os.Handler.dispatchMessage(Handler.java:95)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5221)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

最佳答案

试试这个示例代码来获取个人资料信息

loginButton.registerCallback(callbackManager,
            new FacebookCallback<LoginResult>() {
                @Override
                public void onSuccess(LoginResult loginResult) {
                    // App code

                    // login ok get access token
                    GraphRequest request = GraphRequest.newMeRequest(
                            AccessToken.getCurrentAccessToken(),
                            new GraphRequest.GraphJSONObjectCallback() {
                                @Override
                                public void onCompleted(JSONObject object,
                                        GraphResponse response) {

                                    if (BuildConfig.DEBUG) {
                                        FacebookSdk.setIsDebugEnabled(true);
                                        FacebookSdk
                                                .addLoggingBehavior(LoggingBehavior.INCLUDE_ACCESS_TOKENS);

                                        System.out
                                                .println("AccessToken.getCurrentAccessToken()"
                                                        + AccessToken
                                                                .getCurrentAccessToken()
                                                                .toString());
                                        Profile.getCurrentProfile().getId();
                                        Profile.getCurrentProfile().getFirstName();
                                        Profile.getCurrentProfile().getLastName();
                                        Profile.getCurrentProfile().getProfilePictureUri(50, 50);
                                        //String email=UserManager.asMap().get(“email”).toString();
                                    }
                                }
                            });
                    request.executeAsync(); 
                /*  Bundle parameters = new Bundle();
                    parameters
                            .putString("fields",
                                    "id,firstName,lastName,name,email,gender,birthday,address");
                    request.setParameters(parameters);



                    Intent loginintent = new Intent(getActivity(),
                            EditProfile.class);
                    startActivity(loginintent);
                    System.out.println("XXXX " + getId());
                 */
                    makeJsonObjReq();
                }

                @Override
                public void onCancel() {
                    // App code
                }

                @Override
                public void onError(FacebookException exception) {
                    // App code
                }

            });

    return view;

关于android - 从 Android 上的 Facebook SDK 获取配置文件数据始终返回 Null。为什么？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/29912083/