我正在开发一个应该与 Facebook 集成的 Android 应用程序。我已经阅读了官方指南和其他几个指南，我认为我已经使用 Facebook 登录框架正确实现了所有内容。
但是，SDK 仅在第一次执行成功登录。如果我注销并重试，应用程序将毫无例外地关闭。如果我杀死我的应用程序并从应用程序列表启动它，也会发生同样的情况。
我可以在模拟器和真实设备（Nexus 7）上重现它。
登录活动.java：
package com.everporter.everporter;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import org.json.JSONException;
import org.json.JSONObject;
import com.everporter.everporter.FBLoginFragment.OnFBAccessTokenPass;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.annotation.TargetApi;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.telephony.PhoneNumberUtils;
import android.text.TextUtils;
import android.util.Log;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.View;
import android.view.inputmethod.EditorInfo;
import android.widget.EditText;
import android.widget.TextView;
/**
* Activity which displays a login screen to the user, offering registration as
* well.
*/
public class LoginActivity extends FragmentActivity
implements OnFBAccessTokenPass {
/**
* The default email to populate the email field with.
*/
public static final String EXTRA_EMAIL = "com.example.android.authenticatordemo.extra.EMAIL";
private static final String REST_METHOD_NAME = "/login/";
private static final String SOCIAL_REST_METHOD_NAME = "/validation/";
private static final String TAG = "UserLoginTask";
private static final String FB_TAG = "UserFacebookLoginTask";
/**
* Keep track of the login task to ensure we can cancel it if requested.
*/
private UserLoginTask mAuthTask = null;
private UserFacebookLoginTask mFacebookAuthTask = null;
private String mFacebookAccessToken;
private String mFacebookUserId;
// API URL read from the settings (set in main activity)
private String mRestApiUrl;
private int mConnectionTimeout;
private int mReadTimeout;
private SharedPreferences mPrefs;
// Error message set by the async task, if the error does happen indeed
private String mAsyncTaskErrorMsg;
// Values for email and password at the time of the login attempt.
private String mEmail;
private String mPassword;
private String mSessionCookie; // our session
// UI references.
private EditText mEmailView;
private EditText mPasswordView;
private View mLoginFormView;
private View mLoginStatusView;
private TextView mLoginStatusMessageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
mPrefs = getSharedPreferences("settings", MODE_PRIVATE);
mRestApiUrl = mPrefs.getString("api_url", "");
mConnectionTimeout = mPrefs.getInt("connection_timeout", 3000);
mReadTimeout = mPrefs.getInt("read_timeout", 3000);
// Set up the login form.
mEmail = getIntent().getStringExtra(EXTRA_EMAIL);
mEmailView = (EditText) findViewById(R.id.email);
mEmailView.setText(mEmail);
mPasswordView = (EditText) findViewById(R.id.password);
mPasswordView
.setOnEditorActionListener(new TextView.OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView textView, int id,
KeyEvent keyEvent) {
if (id == R.id.login || id == EditorInfo.IME_NULL) {
attemptLogin();
return true;
}
return false;
}
});
mLoginFormView = findViewById(R.id.login_form);
mLoginStatusView = findViewById(R.id.login_status);
mLoginStatusMessageView = (TextView) findViewById(R.id.login_status_message);
findViewById(R.id.sign_in_button).setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View view) {
attemptLogin();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
getMenuInflater().inflate(R.menu.login, menu);
return true;
}
/**
* Handle Facebook login
*/
@Override
public void onFBAccessTokenPass(String accessToken, String uid) {
// we are passed Facebook access token, successful login
Log.i(TAG, "Facebook access token: " + accessToken);
mFacebookAccessToken = accessToken;
mFacebookUserId = uid;
// Show a progress spinner, and kick off a background task to
// sent the FB token to the server.
mLoginStatusMessageView.setText(R.string.login_progress_signing_in);
showProgress(true);
mFacebookAuthTask = new UserFacebookLoginTask(this);
mFacebookAuthTask.execute((Void) null);
}
/**
* Attempts to sign in or register the account specified by the login form.
* If there are form errors (invalid email, missing fields, etc.), the
* errors are presented and no actual login attempt is made.
*/
public void attemptLogin() {
if (mAuthTask != null) {
return;
}
// Reset errors.
mEmailView.setError(null);
mPasswordView.setError(null);
mAsyncTaskErrorMsg = "";
// Store values at the time of the login attempt.
mEmail = mEmailView.getText().toString();
mPassword = mPasswordView.getText().toString();
boolean cancel = false;
View focusView = null;
// Check for a valid password.
if (TextUtils.isEmpty(mPassword)) {
mPasswordView.setError(getString(R.string.error_field_required));
focusView = mPasswordView;
cancel = true;
} else if (mPassword.length() < 4) {
mPasswordView.setError(getString(R.string.error_invalid_password));
focusView = mPasswordView;
cancel = true;
}
// Check for a valid email address or phone number.
if (TextUtils.isEmpty(mEmail)) {
mEmailView.setError(getString(R.string.error_field_required));
focusView = mEmailView;
cancel = true;
} else if (!android.util.Patterns.EMAIL_ADDRESS.matcher(mEmail).matches() &&
!PhoneNumberUtils.isGlobalPhoneNumber(mEmail)) {
mEmailView.setError(getString(R.string.error_invalid_email));
focusView = mEmailView;
cancel = true;
}
if (cancel) {
// There was an error; don't attempt login and focus the first
// form field with an error.
focusView.requestFocus();
} else {
// Show a progress spinner, and kick off a background task to
// perform the user login attempt.
mLoginStatusMessageView.setText(R.string.login_progress_signing_in);
showProgress(true);
mAuthTask = new UserLoginTask(this);
mAuthTask.execute((Void) null);
}
}
/**
* Shows the progress UI and hides the login form.
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
private void showProgress(final boolean show) {
// On Honeycomb MR2 we have the ViewPropertyAnimator APIs, which allow
// for very easy animations. If available, use these APIs to fade-in
// the progress spinner.
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
int shortAnimTime = getResources().getInteger(
android.R.integer.config_shortAnimTime);
mLoginStatusView.setVisibility(View.VISIBLE);
mLoginStatusView.animate().setDuration(shortAnimTime)
.alpha(show ? 1 : 0)
.setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
mLoginStatusView.setVisibility(show ? View.VISIBLE
: View.GONE);
}
});
mLoginFormView.setVisibility(View.VISIBLE);
mLoginFormView.animate().setDuration(shortAnimTime)
.alpha(show ? 0 : 1)
.setListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
mLoginFormView.setVisibility(show ? View.GONE
: View.VISIBLE);
}
});
} else {
// The ViewPropertyAnimator APIs are not available, so simply show
// and hide the relevant UI components.
mLoginStatusView.setVisibility(show ? View.VISIBLE : View.GONE);
mLoginFormView.setVisibility(show ? View.GONE : View.VISIBLE);
}
}
/**
* Represents an asynchronous login/registration task used to authenticate
* the user.
*/
public class UserLoginTask extends AsyncTask<Void, Void, Boolean> {
private Context mContext;
public UserLoginTask(Context context) {
this.mContext = context;
}
@Override
protected Boolean doInBackground(Void... params) {
Log.i(TAG, "Begin auth...");
HttpURLConnection conn = null;
StringBuilder sb = new StringBuilder();
BufferedOutputStream printout;
boolean signedInOk = false;
try {
URL url = new URL(mRestApiUrl + REST_METHOD_NAME);
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setConnectTimeout(mConnectionTimeout);
conn.setReadTimeout(mReadTimeout);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type","application/json; charset=utf-8");
conn.connect();
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("password", mPassword);
jsonParam.put("username", mEmail);
// Send POST output.
printout = new BufferedOutputStream(conn.getOutputStream());
printout.write(jsonParam.toString().getBytes("UTF-8"));
printout.flush();
printout.close();
int httpCode = conn.getResponseCode();
if (httpCode == HttpURLConnection.HTTP_OK) {
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line + "\n");
}
br.close();
Log.i(TAG, sb.toString());
JSONObject jsonResponse = new JSONObject(sb.toString());
int resultCode = jsonResponse.getInt("code");
if (resultCode == 0) {
// get the session id
String cookie = conn.getHeaderField("Set-Cookie");
if (cookie != null) {
Log.i(TAG, cookie);
signedInOk = true;
mSessionCookie = cookie;
Log.i(TAG, "Authenticated");
}
} else if (resultCode == 2 || resultCode == 3) {
signedInOk = false; // wrong login and password
} else {
// get the error message
if (!jsonResponse.isNull("message")) {
mAsyncTaskErrorMsg = jsonResponse.getString("message");
} else {
mAsyncTaskErrorMsg = getString(R.string.internal_error);
}
}
} else{
Log.e(TAG, conn.getResponseMessage());
}
} catch (JSONException e) {
Log.e(TAG, e.getMessage());
mAsyncTaskErrorMsg = e.getMessage();
} catch (IOException e) {
Log.e(TAG, e.getMessage());
mAsyncTaskErrorMsg = e.getMessage();
} finally {
if (conn != null)
conn.disconnect();
}
Log.i(TAG, "End auth...");
return signedInOk;
}
@Override
protected void onPostExecute(final Boolean success) {
mAuthTask = null;
showProgress(false);
if (success) {
// store the userId
SharedPreferences.Editor ed = mPrefs.edit();
ed.putString("session_cookie", mSessionCookie);
ed.putLong("session_cookie_time", System.currentTimeMillis());
ed.apply();
// start main
Intent intent = new Intent(mContext, MainActivity.class);
startActivity(intent);
finish();
} else {
if (!mAsyncTaskErrorMsg.isEmpty()) {
// show the error message
new AlertDialog.Builder(mContext)
.setTitle("Error occured")
.setMessage(mAsyncTaskErrorMsg)
.setNeutralButton(android.R.string.ok,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
}).show();
} else {
mPasswordView
.setError(getString(R.string.error_incorrect_password));
mPasswordView.requestFocus();
}
}
}
@Override
protected void onCancelled() {
mAuthTask = null;
showProgress(false);
}
}
/**
* Represents an asynchronous login task used to authenticate
* the user via Facebook.
*/
public class UserFacebookLoginTask extends AsyncTask<Void, Void, Boolean> {
private Context mContext;
public UserFacebookLoginTask(Context context) {
this.mContext = context;
}
@Override
protected Boolean doInBackground(Void... params) {
Log.i(FB_TAG, "Begin Facebook validation...");
HttpURLConnection conn = null;
StringBuilder sb = new StringBuilder();
BufferedOutputStream printout;
boolean signedInOk = false;
try {
URL url = new URL(mRestApiUrl + SOCIAL_REST_METHOD_NAME);
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setConnectTimeout(mConnectionTimeout);
conn.setReadTimeout(mReadTimeout);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type","application/json; charset=utf-8");
conn.connect();
//Create JSONObject here
JSONObject jsonParam = new JSONObject();
jsonParam.put("provider", "facebook");
jsonParam.put("token", mFacebookAccessToken);
jsonParam.put("uid", mFacebookUserId);
// Send POST output.
printout = new BufferedOutputStream(conn.getOutputStream());
printout.write(jsonParam.toString().getBytes("UTF-8"));
printout.flush();
printout.close();
int httpCode = conn.getResponseCode();
if (httpCode == HttpURLConnection.HTTP_OK) {
BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream(), "UTF-8"));
String line = null;
while ((line = br.readLine()) != null) {
sb.append(line + "\n");
}
br.close();
Log.i(FB_TAG, sb.toString());
JSONObject jsonResponse = new JSONObject(sb.toString());
int resultCode = jsonResponse.getInt("code");
if (resultCode == 0) {
// get the session id
String cookie = conn.getHeaderField("Set-Cookie");
if (cookie != null) {
Log.i(FB_TAG, cookie);
signedInOk = true;
mSessionCookie = cookie;
Log.i(FB_TAG, "Authenticated");
}
} else if (resultCode == 2 || resultCode == 3) {
signedInOk = false; // no such user in the database
mAsyncTaskErrorMsg = "";
} else {
// get the error message
if (!jsonResponse.isNull("message")) {
mAsyncTaskErrorMsg = jsonResponse.getString("message");
} else {
mAsyncTaskErrorMsg = getString(R.string.internal_error);
}
}
} else{
Log.e(FB_TAG, conn.getResponseMessage());
}
} catch (JSONException e) {
Log.e(FB_TAG, e.getMessage());
mAsyncTaskErrorMsg = e.getMessage();
} catch (IOException e) {
Log.e(FB_TAG, e.getMessage());
mAsyncTaskErrorMsg = e.getMessage();
} finally {
if (conn != null)
conn.disconnect();
}
Log.i(FB_TAG, "End auth...");
return signedInOk;
}
@Override
protected void onPostExecute(final Boolean success) {
mFacebookAuthTask = null;
showProgress(false);
if (success) {
// store the userId
SharedPreferences.Editor ed = mPrefs.edit();
ed.putString("session_cookie", mSessionCookie);
ed.putLong("session_cookie_time", System.currentTimeMillis());
ed.apply();
// start main
Intent intent = new Intent(mContext, MainActivity.class);
startActivity(intent);
finish();
} else {
if (!mAsyncTaskErrorMsg.isEmpty()) {
// show the error message
new AlertDialog.Builder(mContext)
.setTitle("Error occured")
.setMessage(mAsyncTaskErrorMsg)
.setNeutralButton(android.R.string.ok,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
}).show();
}
}
}
@Override
protected void onCancelled() {
mFacebookAuthTask = null;
showProgress(false);
}
}
}
FBLoginFragment.java：
package com.everporter.everporter;
import java.util.Arrays;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.facebook.Request;
import com.facebook.Response;
import com.facebook.Session;
import com.facebook.SessionState;
import com.facebook.UiLifecycleHelper;
import com.facebook.model.GraphUser;
import com.facebook.widget.LoginButton;
public class FBLoginFragment extends Fragment {
private static final String TAG = "FBLoginFragment";
private UiLifecycleHelper mUiHelper;
private OnFBAccessTokenPass mTokenPasser;
private String mSessionToken;
private Session.StatusCallback callback = new Session.StatusCallback() {
@Override
public void call(Session session, SessionState state, Exception exception) {
onSessionStateChange(session, state, exception);
}
};
private void onSessionStateChange(Session session, SessionState state, Exception exception) {
if (state.isOpened()) {
Log.i(TAG, "Logged in...");
mSessionToken = session.getAccessToken();
// Request user data and show the results
Request.executeMeRequestAsync(session, new Request.GraphUserCallback() {
@Override
public void onCompleted(GraphUser user, Response response) {
if (user != null) {
// pass the access token to the activity
// with the user id
mTokenPasser.onFBAccessTokenPass(mSessionToken, user.getId());
}
}
});
} else if (state.isClosed()) {
Log.i(TAG, "Logged out...");
mSessionToken = "";
}
}
public interface OnFBAccessTokenPass {
public void onFBAccessTokenPass(String accessToken, String uid);
}
@Override
public void onAttach(Activity a) {
super.onAttach(a);
mTokenPasser = (OnFBAccessTokenPass) a;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mUiHelper = new UiLifecycleHelper(getActivity(), callback);
mUiHelper.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fb_login_fragment, container, false);
LoginButton authButton = (LoginButton) view.findViewById(R.id.authButton);
authButton.setFragment(this);
authButton.setReadPermissions(Arrays.asList("email"));
return view;
}
@Override
public void onResume() {
super.onResume();
// For scenarios where the main activity is launched and user
// session is not null, the session state change notification
// may not be triggered. Trigger it if it's open/closed.
Session session = Session.getActiveSession();
if (session != null &&
(session.isOpened() || session.isClosed()) ) {
onSessionStateChange(session, session.getState(), null);
}
mUiHelper.onResume();
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
mUiHelper.onActivityResult(requestCode, resultCode, data);
}
@Override
public void onPause() {
super.onPause();
mUiHelper.onPause();
}
@Override
public void onDestroy() {
super.onDestroy();
mUiHelper.onDestroy();
}
@Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
mUiHelper.onSaveInstanceState(outState);
}
}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.everporter.everporter"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="10"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.everporter.everporter.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.everporter.everporter.LoginActivity"
android:label="@string/title_activity_login"
android:noHistory="true"
android:excludeFromRecents="true"
android:windowSoftInputMode="adjustResize|stateVisible" >
</activity>
<meta-data android:name="com.facebook.sdk.ApplicationId" android:value="@string/fb_app_id"/>
<activity android:name="com.facebook.LoginActivity" android:label="@string/app_name"></activity>
</application>
</manifest>