我第一次使用 facebook SDK 登录时，它可以正常工作。但是当我尝试注销并再次登录时，会出现 facebook 错误。错误是"Facebook error: an active access token must be used to query information about the current user"并且getAccessToken()返回为空。任何答案和评论将不胜感激。
登录Activity.java
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (APP_ID == null) {
Util.showAlert(this, "Warning", "Facebook Application ID must be specified before running");
}
try {
PackageInfo info = getPackageManager().getPackageInfo("com.ff.fbin", PackageManager.GET_SIGNATURES);
for (Signature signature : info.signatures) {
MessageDigest md = MessageDigest.getInstance("SHA");
md.update(signature.toByteArray());
Log.e("TAG", "Reverse FB key: "+Base64Coder.encodeLines(md.digest()));
}
} catch (NameNotFoundException e) {
} catch (NoSuchAlgorithmException e) {
}
mLoginButton = (LoginButton) findViewById(R.id.login);
mFacebook = new Facebook(APP_ID);
mAsyncRunner = new AsyncFacebookRunner(mFacebook);
SessionStore.restore(mFacebook, this);
SessionEvents.addAuthListener(new SampleAuthListener());
SessionEvents.addLogoutListener(new SampleLogoutListener());
mLoginButton.init(this, mFacebook, mPermissions);
}
@Override
protected void onActivityResult(int requestCode, int resultCode,
Intent data) {
mFacebook.authorizeCallback(requestCode, resultCode, data);
boolean isLogined = mFacebook.isSessionValid();
Log.i(TAG, "getAccessToken, onActivity:" +mFacebook.getAccessToken());
if (isLogined){
mAsyncRunner.request("me", new SampleRequestListener());
}
}
public class SampleRequestListener extends BaseRequestListener {
@Override
public void onComplete(final String response, final Object state) {
try {
Log.d(TAG, "Response2: " + response.toString());
JSONObject json = Util.parseJson(response);
//Retrieve user information from facebook
final Runnable mUpdateResultsSuccess = new Runnable() {
@Override
public void run() {
updateResultsInUiSuccess();
}
};
private void updateResultsInUiSuccess() {
if (loginSuccess){
Log.i(TAG, "Login FB done");
finish();
Intent intent2 = new Intent(LoginScreen.this, MainMenu.class);
helper.insert_user(mFacebook.getAccessToken());
intent2.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent2);
} else {
loading_text.setText("Error Processing");
Log.i(TAG, "Login FB failed");
try {
mFacebook.logout(this);
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
Log.e(TAG, "MalformedURLException: "+e.getMessage());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
Log.e(TAG, "IOException: "+e.getMessage());
}
SessionStore.clear(this);
pDialog.dismiss();
Toast.makeText(LoginScreen.this, "Login Failed. Please try again", Toast.LENGTH_LONG).show();
}
}
public class SampleAuthListener implements com.ff.fbin.SessionEvents.AuthListener {
@Override
public void onAuthSucceed() {
Log.i(TAG, "You have logged in! ");
boolean isLogined = mFacebook.isSessionValid();
Log.i(TAG, "isLogined: "+isLogined);
if(!isFinishing()){
};
if (isLogined){
mAsyncRunner.request("me", new SampleRequestListener());
pDialog.setMessage("Login in process......");
pDialog.show();
}
}
@Override
public void onAuthFail(String error) {
Log.i(TAG, "Login Failed: " + error);
Toast.makeText(getApplicationContext(), "Login Failed: " + error, Toast.LENGTH_LONG).show();
pDialog.dismiss();
}
}
public class SampleLogoutListener implements com.ff.fbin.SessionEvents.LogoutListener {
@Override
public void onLogoutBegin() {
Log.i(TAG, "Logging out...");
}
@Override
public void onLogoutFinish() {
Log.i(TAG, "You have logged out! ");
}
}