/**
* 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.scrumptious;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.Menu;
import android.view.MenuItem;
import com.facebook.Session;
import com.facebook.SessionState;
import com.facebook.UiLifecycleHelper;
public class MainActivity extends FragmentActivity {
private static final int SPLASH = 0;
private static final int SELECTION = 1;
private static final int SETTINGS = 2;
private static final int FRAGMENT_COUNT = SETTINGS +1;
private Fragment[] fragments = new Fragment[FRAGMENT_COUNT];
private MenuItem settings;
private boolean isResumed = false;
private UiLifecycleHelper uiHelper;
private Session.StatusCallback callback = new Session.StatusCallback() {
@Override
public void call(Session session, SessionState state, Exception exception) {
onSessionStateChange(session, state, exception);
}
};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
uiHelper = new UiLifecycleHelper(this, callback);
uiHelper.onCreate(savedInstanceState);
setContentView(R.layout.main);
FragmentManager fm = getSupportFragmentManager();
fragments[SPLASH] = fm.findFragmentById(R.id.splashFragment);
fragments[SELECTION] = fm.findFragmentById(R.id.selectionFragment);
fragments[SETTINGS] = fm.findFragmentById(R.id.userSettingsFragment);
FragmentTransaction transaction = fm.beginTransaction();
for(int i = 0; i < fragments.length; i++) {
transaction.hide(fragments[i]);
}
transaction.commit();
}
@Override
public void onResume() {
super.onResume();
uiHelper.onResume();
isResumed = true;
}
@Override
public void onPause() {
super.onPause();
uiHelper.onPause();
isResumed = false;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
uiHelper.onActivityResult(requestCode, resultCode, data);
}
@Override
public void onDestroy() {
super.onDestroy();
uiHelper.onDestroy();
}
@Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
uiHelper.onSaveInstanceState(outState);
}
@Override
protected void onResumeFragments() {
super.onResumeFragments();
Session session = Session.getActiveSession();
if (session != null && session.isOpened()) {
// if the session is already open, try to show the selection fragment
showFragment(SELECTION, false);
} else {
// otherwise present the splash screen and ask the user to login.
showFragment(SPLASH, false);
}
}
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
// only add the menu when the selection fragment is showing
if (fragments[SELECTION].isVisible()) {
if (menu.size() == 0) {
settings = menu.add(R.string.settings);
}
return true;
} else {
menu.clear();
settings = null;
}
return false;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.equals(settings)) {
showFragment(SETTINGS, true);
return true;
}
return false;
}
private void onSessionStateChange(Session session, SessionState state, Exception exception) {
if (isResumed) {
FragmentManager manager = getSupportFragmentManager();
int backStackSize = manager.getBackStackEntryCount();
for (int i = 0; i < backStackSize; i++) {
manager.popBackStack();
}
// check for the OPENED state instead of session.isOpened() since for the
// OPENED_TOKEN_UPDATED state, the selection fragment should already be showing.
if (state.equals(SessionState.OPENED)) {
showFragment(SELECTION, false);
} else if (state.isClosed()) {
showFragment(SPLASH, false);
}
}
}
private void showFragment(int fragmentIndex, boolean addToBackStack) {
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction transaction = fm.beginTransaction();
for (int i = 0; i < fragments.length; i++) {
if (i == fragmentIndex) {
transaction.show(fragments[i]);
} else {
transaction.hide(fragments[i]);
}
}
if (addToBackStack) {
transaction.addToBackStack(null);
}
transaction.commit();
}
}