/**
* Copyright 2010-present Facebook.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.facebook;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.support.v4.content.LocalBroadcastManager;
import android.util.Log;
import com.facebook.internal.NativeProtocol;
import com.facebook.widget.FacebookDialog;
import java.util.UUID;
/**
* This class helps to create, automatically open (if applicable), save, and
* restore the Active Session in a way that is similar to Android UI lifecycles.
* <p>
* When using this class, clients MUST call all the public methods from the
* respective methods in either an Activity or Fragment. Failure to call all the
* methods can result in improperly initialized or uninitialized Sessions.
* <p>
* This class should also be used by Activities that will be displaying native dialogs
* provided by the Facebook application, in order to handle processing of the activity
* results generated by those dialogs.
*/
public class UiLifecycleHelper {
private static final String DIALOG_CALL_BUNDLE_SAVE_KEY =
"com.facebook.UiLifecycleHelper.pendingFacebookDialogCallKey";
private final static String ACTIVITY_NULL_MESSAGE = "activity cannot be null";
private final Activity activity;
private final Session.StatusCallback callback;
private final BroadcastReceiver receiver;
private final LocalBroadcastManager broadcastManager;
// Members related to handling FacebookDialog calls
private FacebookDialog.PendingCall pendingFacebookDialogCall;
private AppEventsLogger appEventsLogger;
/**
* Creates a new UiLifecycleHelper.
*
* @param activity the Activity associated with the helper. If calling from a Fragment,
* use {@link android.support.v4.app.Fragment#getActivity()}
* @param callback the callback for Session status changes, can be null
*/
public UiLifecycleHelper(Activity activity, Session.StatusCallback callback) {
if (activity == null) {
throw new IllegalArgumentException(ACTIVITY_NULL_MESSAGE);
}
this.activity = activity;
this.callback = callback;
this.receiver = new ActiveSessionBroadcastReceiver();
this.broadcastManager = LocalBroadcastManager.getInstance(activity);
}
/**
* To be called from an Activity or Fragment's onCreate method.
*
* @param savedInstanceState the previously saved state
*/
public void onCreate(Bundle savedInstanceState) {
Session session = Session.getActiveSession();
if (session == null) {
if (savedInstanceState != null) {
session = Session.restoreSession(activity, null, callback, savedInstanceState);
}
if (session == null) {
session = new Session(activity);
}
Session.setActiveSession(session);
}
if (savedInstanceState != null) {
pendingFacebookDialogCall = savedInstanceState.getParcelable(DIALOG_CALL_BUNDLE_SAVE_KEY);
}
}
/**
* To be called from an Activity or Fragment's onResume method.
*/
public void onResume() {
Session session = Session.getActiveSession();
if (session != null) {
if (callback != null) {
session.addCallback(callback);
}
if (SessionState.CREATED_TOKEN_LOADED.equals(session.getState())) {
session.openForRead(null);
}
}
// add the broadcast receiver
IntentFilter filter = new IntentFilter();
filter.addAction(Session.ACTION_ACTIVE_SESSION_SET);
filter.addAction(Session.ACTION_ACTIVE_SESSION_UNSET);
// Add a broadcast receiver to listen to when the active Session
// is set or unset, and add/remove our callback as appropriate
broadcastManager.registerReceiver(receiver, filter);
}
/**
* To be called from an Activity or Fragment's onActivityResult method.
*
* @param requestCode the request code
* @param resultCode the result code
* @param data the result data
*/
public void onActivityResult(int requestCode, int resultCode, Intent data) {
onActivityResult(requestCode, resultCode, data, null);
}
/**
* To be called from an Activity or Fragment's onActivityResult method, when the results of a FacebookDialog
* call are expected.
*
* @param requestCode the request code
* @param resultCode the result code
* @param data the result data
* @param dialogCallback the callback for handling FacebookDialog results, can be null
*/
public void onActivityResult(int requestCode, int resultCode, Intent data,
FacebookDialog.Callback facebookDialogCallback) {
Session session = Session.getActiveSession();
if (session != null) {
session.onActivityResult(activity, requestCode, resultCode, data);
}
handleFacebookDialogActivityResult(requestCode, resultCode, data, facebookDialogCallback);
}
/**
* To be called from an Activity or Fragment's onSaveInstanceState method.
*
* @param outState the bundle to save state in
*/
public void onSaveInstanceState(Bundle outState) {
Session.saveSession(Session.getActiveSession(), outState);
outState.putParcelable(DIALOG_CALL_BUNDLE_SAVE_KEY, pendingFacebookDialogCall);
}
/**
* To be called from an Activity or Fragment's onPause method.
*/
public void onPause() {
// remove the broadcast receiver
broadcastManager.unregisterReceiver(receiver);
if (callback != null) {
Session session = Session.getActiveSession();
if (session != null) {
session.removeCallback(callback);
}
}
}
/**
* To be called from an Activity or Fragment's onStop method.
*/
public void onStop() {
AppEventsLogger.onContextStop();
}
/**
* To be called from an Activity or Fragment's onDestroy method.
*/
public void onDestroy() {
}
/**
* Register that we are expecting results from a call to the Facebook application (e.g., from a native
* dialog provided by the Facebook app). Activity results forwarded to onActivityResults will be parsed
* and handled if they correspond to this call. Only a single pending FacebookDialog call can be tracked
* at a time; attempting to track another one will cancel the first one.
* @param appCall an PendingCall object containing the call ID
*/
public void trackPendingDialogCall(FacebookDialog.PendingCall pendingCall) {
if (pendingFacebookDialogCall != null) {
// If one is already pending, cancel it; we don't allow multiple pending calls.
Log.i("Facebook", "Tracking new app call while one is still pending; canceling pending call.");
cancelPendingAppCall(null);
}
pendingFacebookDialogCall = pendingCall;
}
/**
* Retrieves an instance of AppEventsLogger that can be used for the current Session, if any. Different
* instances may be returned if the current Session changes, so this value should not be cached for long
* periods of time -- always call getAppEventsLogger to get the right logger for the current Session. If
* no Session is currently available, this method will return null.
*
* To ensure delivery of app events across Activity lifecycle events, calling Activities should be sure to
* call the onStop method.
*
* @return an AppEventsLogger to use for logging app events
*/
public AppEventsLogger getAppEventsLogger() {
Session session = Session.getActiveSession();
if (session == null) {
return null;
}
if (appEventsLogger == null || !appEventsLogger.isValidForSession(session)) {
if (appEventsLogger != null) {
// Pretend we got stopped so the old logger will persist its results now, in case we get stopped
// before events get flushed.
AppEventsLogger.onContextStop();
}
appEventsLogger = AppEventsLogger.newLogger(activity, session);
}
return appEventsLogger;
}
/**
* The BroadcastReceiver implementation that either adds or removes the callback
* from the active Session object as it's SET or UNSET.
*/
private class ActiveSessionBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
if (Session.ACTION_ACTIVE_SESSION_SET.equals(intent.getAction())) {
Session session = Session.getActiveSession();
if (session != null && callback != null) {
session.addCallback(callback);
}
} else if (Session.ACTION_ACTIVE_SESSION_UNSET.equals(intent.getAction())) {
Session session = Session.getActiveSession();
if (session != null && callback != null) {
session.removeCallback(callback);
}
}
}
}
private boolean handleFacebookDialogActivityResult(int requestCode, int resultCode, Intent data,
FacebookDialog.Callback facebookDialogCallback) {
if (pendingFacebookDialogCall == null || pendingFacebookDialogCall.getRequestCode() != requestCode) {
return false;
}
if (data == null) {
// We understand the request code, but have no Intent. This can happen if the called Activity crashes
// before it can be started; we treat this as a cancellation because we have no other information.
cancelPendingAppCall(facebookDialogCallback);
return true;
}
String callIdString = data.getStringExtra(NativeProtocol.EXTRA_PROTOCOL_CALL_ID);
UUID callId = null;
if (callIdString != null) {
try {
callId = UUID.fromString(callIdString);
} catch (IllegalArgumentException exception) {
}
}
// Was this result for the call we are waiting on?
if (callId != null && pendingFacebookDialogCall.getCallId().equals(callId)) {
// Yes, we can handle it normally.
FacebookDialog.handleActivityResult(activity, pendingFacebookDialogCall, requestCode, data,
facebookDialogCallback);
} else {
// No, send a cancellation error to the pending call and ignore the result, because we
// don't know what to do with it.
cancelPendingAppCall(facebookDialogCallback);
}
pendingFacebookDialogCall = null;
return true;
}
private void cancelPendingAppCall(FacebookDialog.Callback facebookDialogCallback) {
if (facebookDialogCallback != null) {
Intent pendingIntent = pendingFacebookDialogCall.getRequestIntent();
Intent cancelIntent = new Intent();
cancelIntent.putExtra(NativeProtocol.EXTRA_PROTOCOL_CALL_ID,
pendingIntent.getStringExtra(NativeProtocol.EXTRA_PROTOCOL_CALL_ID));
cancelIntent.putExtra(NativeProtocol.EXTRA_PROTOCOL_ACTION,
pendingIntent.getStringExtra(NativeProtocol.EXTRA_PROTOCOL_ACTION));
cancelIntent.putExtra(NativeProtocol.EXTRA_PROTOCOL_VERSION,
pendingIntent.getIntExtra(NativeProtocol.EXTRA_PROTOCOL_VERSION, 0));
cancelIntent.putExtra(NativeProtocol.STATUS_ERROR_TYPE, NativeProtocol.ERROR_UNKNOWN_ERROR);
FacebookDialog.handleActivityResult(activity, pendingFacebookDialogCall,
pendingFacebookDialogCall.getRequestCode(), cancelIntent, facebookDialogCallback);
}
pendingFacebookDialogCall = null;
}
}