我刚刚在android上了解了facebook SDK。我已经在stackoverflow和facebook开发者指南上搜索登录，但是当我从facebook sdk获取个人资料数据时我仍然感到困惑。我尝试从unable get profile和Get email实施解决方案，但仍然卡住了。
有我的代码：
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();
}
}
并且有我的日志猫：
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)
答案 0 :(得分：5)
尝试使用此示例代码获取个人资料信息
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;
答案 1 :(得分：1)
我遇到了同样的错误，终于找到了解决方案。基本上你必须首先知道是什么导致了这次崩溃/ NullPointerException。因此，要找出导致此异常的原因，请使您的onComplete代码块如下所示：
GraphRequest request = GraphRequest.newMeRequest(
loginResult.getAccessToken(),
new GraphRequest.GraphJSONObjectCallback() {
@Override
public void onCompleted(
JSONObject object,
GraphResponse response) {
Log.v("LoginActivity Response ", response.toString());
}
});
现在，运行您的应用并尝试使用FB按钮登录。继续检查你的logcat，很快就会看到如下所示的行：
V/LoginActivity Response: {Response: responseCode: 200, graphObject: {"id":"10206735777938523","name":"Rohit Paniker","email":"rohit.paniker.1990@gmail.com","gender":"male"}, error: null}
我正在使用“年龄”权限，该权限导致ID，名称，电子邮件中的NullPointerException以及我从上面的logcat输出中获知的所有权限。根据输出，我理解为什么崩溃发生了，我删除了object.getString（“age”）并再次运行应用程序，完美运行而没有崩溃，我从ID到名称和电子邮件获得所有数据！
答案 2 :(得分：0)
请参阅下面的工作代码以获取个人资料详情FB SDK 4
//Initialize Facebook SDK
FacebookSdk.sdkInitialize(getApplicationContext());
//if the facebook profile is changed, below code block will be called
profileTracker = new ProfileTracker() {
@Override
protected void onCurrentProfileChanged(Profile oldProfile, Profile currentProfile) {
if(currentProfile != null){
fbUserId = currentProfile.getId();
if(!sharedPreferences.contains("UserName")){
editor.putString("UserName",currentProfile.getFirstName()+" "+currentProfile.getLastName());
}
if(!sharedPreferences.contains("FbId")){
editor.putString("FbId",currentProfile.getId());
}
if(!sharedPreferences.contains("ProfilePicture")){
editor.putString("ProfilePicture",currentProfile.getProfilePictureUri(100,100).toString());
}
editor.commit();
}
}
};
//when new fb user logged in , below code block will be called
AccessTokenTracker accessTokenTracker = new AccessTokenTracker() {
@Override
protected void onCurrentAccessTokenChanged(AccessToken accessToken, AccessToken accessToken2) {
System.out.println("acesstoken trackercalled");
}
};
//set layout resource
setContentView(R.layout.activity_login);
//fb login button
loginButton = (LoginButton) findViewById(R.id.connectWithFbButton);
//set fb permissions
loginButton.setReadPermissions(Arrays.asList("public_profile,email"));
//call the login callback manager
callbackManager = CallbackManager.Factory.create();
LoginManager.getInstance().registerCallback(callbackManager,
new FacebookCallback<LoginResult>() {
@Override
public void onSuccess(LoginResult loginResult) {
profile = Profile.getCurrentProfile();
if(profile != null){
fbUserId = profile.getId();
if(!sharedPreferences.contains("UserName")){
editor.putString("UserName",profile.getFirstName()+" "+profile.getLastName());
}
if(!sharedPreferences.contains("FbId")){
editor.putString("FbId",profile.getId());
}
if(!sharedPreferences.contains("ProfilePicture")){
editor.putString("ProfilePicture",profile.getProfilePictureUri(20,20).toString());
}
editor.commit();
}
goToNewActivity();
}
@Override
public void onCancel() {
}
@Override
public void onError(FacebookException e) {
}
});
答案 3 :(得分：0)
请尝试使用以下代码：
LoginManager.getInstance（）。logInWithReadPermissions（Activity.this， Arrays.asList（“ public_profile”，“电子邮件”）））;
LoginManager.getInstance().registerCallback(callbackManager,
new FacebookCallback<LoginResult>() {
public void onSuccess(LoginResult loginResult) {
if (AccessToken.getCurrentAccessToken() != null) {
Log.e("idfb",""+loginResult.getAccessToken().getUserId());
GraphRequest request = GraphRequest.newMeRequest(
loginResult.getAccessToken(),
new GraphRequest.GraphJSONObjectCallback() {
@Override
public void onCompleted(JSONObject object, GraphResponse response) {
// Application code
try {
Log.i("Response",response.toString());
String email = response.getJSONObject().getString("email");
String name = response.getJSONObject().getString("name");
String id = response.getJSONObject().getString("id");
String imgUrl = "https://graph.facebook.com/" + id + "/picture?type=large";
Log.i("Login" + "Email", "");
Log.i("Login"+ "FirstName", name);
Log.i("Login" + "Id", id);
} catch (JSONException e) {
e.printStackTrace();
Log.e("errorfb",""+e);
}
}
});
Bundle parameters = new Bundle();
parameters.putString("fields", "id,email,name,link");
request.setParameters(parameters);
request.executeAsync();
}
}
@Override
public void onCancel() {
}
@Override
public void onError(FacebookException exception) {
}
});