Java tutorial
/* * Copyright 2014 Google Inc. All rights reserved. * * 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.google.samples.apps.iosched.service; import android.Manifest; import android.app.IntentService; import android.content.ContentProviderOperation; import android.content.ContentResolver; import android.content.ContentValues; import android.content.Intent; import android.content.OperationApplicationException; import android.content.pm.PackageManager; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.os.RemoteException; import android.provider.CalendarContract; import android.support.v4.content.ContextCompat; import android.text.TextUtils; import android.util.Log; import com.google.samples.apps.iosched.Config; import com.google.samples.apps.iosched.R; import com.google.samples.apps.iosched.provider.ScheduleContract; import com.google.samples.apps.iosched.settings.SettingsUtils; import com.google.samples.apps.iosched.util.AccountUtils; import java.util.ArrayList; import static com.google.samples.apps.iosched.util.LogUtils.LOGD; import static com.google.samples.apps.iosched.util.LogUtils.LOGE; import static com.google.samples.apps.iosched.util.LogUtils.LOGW; import static com.google.samples.apps.iosched.util.LogUtils.makeLogTag; /** * Background {@link android.app.Service} that adds or removes session Calendar events through the * {@link CalendarContract} API available in Android 4.0 or above. * <p/> * As of Android M the Calendar data is protected by a permission classified in the dangerous * permissions category. This means the permission needs to be requested as a runtime permission. * Since Calendar sync is an optional feature that is enabled from the settings screen we request * the permission there. Since the code that performs the sync is here and runs asynchronously we * simply no-op when the permission has been revoked. This honors the explicit user decision to * revoke (and possible regrant) the permission. We've chosen not to disable the calendar sync when * this state is detected in case a user comes back to the app wondering why the Calendar entries * still exist. When they disable the feature the permission is requested (to remove any previously * added entries) and if they deny that then they are notified that their Calendar might not have * been cleaned of entries. We've also chosen not to use a notification because the revocation of * the permission isn't critical to the app's functionality and it is typically an explicit decision * by the user. (Technically device admin apps can also responded to permissions request.) */ public class SessionCalendarService extends IntentService { public static final String ACTION_ADD_SESSION_CALENDAR = "com.google.samples.apps.iosched.action.ADD_SESSION_CALENDAR"; public static final String ACTION_CLEAR_ALL_SESSIONS_CALENDAR = "com.google.samples.apps.iosched.action.CLEAR_ALL_SESSIONS_CALENDAR"; public static final String ACTION_REMOVE_SESSION_CALENDAR = "com.google.samples.apps.iosched.action.REMOVE_SESSION_CALENDAR"; public static final String ACTION_UPDATE_ALL_SESSIONS_CALENDAR = "com.google.samples.apps.iosched.action.UPDATE_ALL_SESSIONS_CALENDAR"; public static final String ACTION_UPDATE_ALL_SESSIONS_CALENDAR_COMPLETED = "com.google.samples.apps.iosched.action.UPDATE_CALENDAR_COMPLETED"; public static final String EXTRA_ACCOUNT_NAME = "com.google.samples.apps.iosched.extra.ACCOUNT_NAME"; public static final String EXTRA_SESSION_END = "com.google.samples.apps.iosched.extra.SESSION_BLOCK_END"; public static final String EXTRA_SESSION_ROOM = "com.google.samples.apps.iosched.extra.SESSION_ROOM"; public static final String EXTRA_SESSION_START = "com.google.samples.apps.iosched.extra.SESSION_BLOCK_START"; public static final String EXTRA_SESSION_TITLE = "com.google.samples.apps.iosched.extra.SESSION_TITLE"; // TODO: localize private static final String CALENDAR_CLEAR_SEARCH_LIKE_EXPRESSION = "%added by Google I/O Android app%"; private static final long INVALID_CALENDAR_ID = -1; private static final String TAG = makeLogTag(SessionCalendarService.class); public SessionCalendarService() { super(TAG); } @Override protected void onHandleIntent(Intent intent) { if (!permissionsAlreadyGranted()) { LOGW(TAG, "Calendar permission not granted."); return; } final String action = intent.getAction(); LOGD(TAG, "Received intent: " + action); final ContentResolver resolver = getContentResolver(); boolean isAddEvent = false; if (ACTION_ADD_SESSION_CALENDAR.equals(action)) { isAddEvent = true; } else if (ACTION_REMOVE_SESSION_CALENDAR.equals(action)) { isAddEvent = false; } else if (ACTION_UPDATE_ALL_SESSIONS_CALENDAR.equals(action) && SettingsUtils.shouldSyncCalendar(this)) { try { getContentResolver().applyBatch(CalendarContract.AUTHORITY, processAllSessionsCalendar(resolver, getCalendarId(intent))); sendBroadcast(new Intent(SessionCalendarService.ACTION_UPDATE_ALL_SESSIONS_CALENDAR_COMPLETED)); } catch (RemoteException | OperationApplicationException e) { LOGE(TAG, "Error adding all sessions to Google Calendar", e); } } else if (ACTION_CLEAR_ALL_SESSIONS_CALENDAR.equals(action)) { try { getContentResolver().applyBatch(CalendarContract.AUTHORITY, processClearAllSessions(resolver, getCalendarId(intent))); } catch (RemoteException | OperationApplicationException e) { LOGE(TAG, "Error clearing all sessions from Google Calendar", e); } } else { return; } final Uri uri = intent.getData(); final Bundle extras = intent.getExtras(); if (uri == null || extras == null || !SettingsUtils.shouldSyncCalendar(this)) { return; } try { resolver.applyBatch(CalendarContract.AUTHORITY, processSessionCalendar(resolver, getCalendarId(intent), isAddEvent, uri, extras.getLong(EXTRA_SESSION_START), extras.getLong(EXTRA_SESSION_END), extras.getString(EXTRA_SESSION_TITLE), extras.getString(EXTRA_SESSION_ROOM))); } catch (RemoteException | OperationApplicationException e) { LOGE(TAG, "Error adding session to Google Calendar", e); } } /** * Gets the currently-logged in user's Google Calendar, or the Google Calendar for the user * specified in the given intent's {@link #EXTRA_ACCOUNT_NAME}. */ private long getCalendarId(Intent intent) { final String accountName; if (intent != null && intent.hasExtra(EXTRA_ACCOUNT_NAME)) { accountName = intent.getStringExtra(EXTRA_ACCOUNT_NAME); } else { accountName = AccountUtils.getActiveAccountName(this); } if (TextUtils.isEmpty(accountName) || !permissionsAlreadyGranted()) { return INVALID_CALENDAR_ID; } // TODO: The calendar ID should be stored in shared settings_prefs upon choosing an account. @SuppressWarnings("MissingPermission") Cursor calendarsCursor = getContentResolver().query(CalendarContract.Calendars.CONTENT_URI, new String[] { "_id" }, // TODO: What if the calendar is not displayed or not sync'd? "account_name = ownerAccount and account_name = ?", new String[] { accountName }, null); long calendarId = INVALID_CALENDAR_ID; if (calendarsCursor != null && calendarsCursor.moveToFirst()) { calendarId = calendarsCursor.getLong(0); calendarsCursor.close(); } return calendarId; } private String makeCalendarEventTitle(String sessionTitle) { return sessionTitle + getResources().getString(R.string.session_calendar_suffix); } private boolean permissionsAlreadyGranted() { return ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.WRITE_CALENDAR) == PackageManager.PERMISSION_GRANTED; } /** * Processes all sessions in the * {@link com.google.samples.apps.iosched.provider.ScheduleProvider}, * adding or removing calendar events to/from the specified Google Calendar depending on whether * a session is in the user's schedule or not. */ private ArrayList<ContentProviderOperation> processAllSessionsCalendar(ContentResolver resolver, final long calendarId) { ArrayList<ContentProviderOperation> batch = new ArrayList<ContentProviderOperation>(); // Unable to find the Calendar associated with the user. Stop here. if (calendarId == INVALID_CALENDAR_ID) { return batch; } // Retrieves all sessions. For each session, add to Calendar if starred and attempt to // remove from Calendar if unstarred. Cursor cursor = resolver.query(ScheduleContract.Sessions.CONTENT_URI, SessionsQuery.PROJECTION, null, null, null); if (cursor != null) { while (cursor.moveToNext()) { Uri uri = ScheduleContract.Sessions.buildSessionUri(Long.valueOf(cursor.getLong(0)).toString()); boolean isAddEvent = (cursor.getInt(SessionsQuery.SESSION_IN_MY_SCHEDULE) == 1); if (isAddEvent) { batch.addAll(processSessionCalendar(resolver, calendarId, isAddEvent, uri, cursor.getLong(SessionsQuery.SESSION_START), cursor.getLong(SessionsQuery.SESSION_END), cursor.getString(SessionsQuery.SESSION_TITLE), cursor.getString(SessionsQuery.ROOM_NAME))); } } cursor.close(); } return batch; } /** * Removes all calendar entries associated with Google I/O. */ private ArrayList<ContentProviderOperation> processClearAllSessions(ContentResolver resolver, long calendarId) { ArrayList<ContentProviderOperation> batch = new ArrayList<ContentProviderOperation>(); // Unable to find the Calendar associated with the user. Stop here. if (calendarId == INVALID_CALENDAR_ID) { Log.e(TAG, "Unable to find Calendar for user"); return batch; } // Delete all calendar entries matching the given title within the given time period batch.add(ContentProviderOperation.newDelete(CalendarContract.Events.CONTENT_URI).withSelection( CalendarContract.Events.CALENDAR_ID + " = ? and " + CalendarContract.Events.TITLE + " LIKE ? and " + CalendarContract.Events.DTSTART + ">= ? and " + CalendarContract.Events.DTEND + "<= ?", new String[] { Long.toString(calendarId), CALENDAR_CLEAR_SEARCH_LIKE_EXPRESSION, Long.toString(Config.CONFERENCE_START_MILLIS), Long.toString(Config.CONFERENCE_END_MILLIS) }) .build()); return batch; } /** * Adds or removes a single session to/from the specified Google Calendar. */ private ArrayList<ContentProviderOperation> processSessionCalendar(final ContentResolver resolver, final long calendarId, final boolean isAddEvent, final Uri sessionUri, final long sessionBlockStart, final long sessionBlockEnd, final String sessionTitle, final String sessionRoom) { ArrayList<ContentProviderOperation> batch = new ArrayList<ContentProviderOperation>(); // Unable to find the Calendar associated with the user or permissions were revoked. if (calendarId == INVALID_CALENDAR_ID || !permissionsAlreadyGranted()) { return batch; } final String calendarEventTitle = makeCalendarEventTitle(sessionTitle); Cursor cursor; ContentValues values = new ContentValues(); // Add Calendar event. if (isAddEvent) { if (sessionBlockStart == 0L || sessionBlockEnd == 0L || sessionTitle == null) { LOGW(TAG, "Unable to add a Calendar event due to insufficient input parameters."); return batch; } // Check if the calendar event exists first. If it does, we don't want to add a // duplicate one. //noinspection MissingPermission cursor = resolver.query(CalendarContract.Events.CONTENT_URI, // URI new String[] { CalendarContract.Events._ID }, // Projection CalendarContract.Events.CALENDAR_ID + "=? and " // Selection + CalendarContract.Events.TITLE + "=? and " + CalendarContract.Events.DTSTART + ">=? and " + CalendarContract.Events.DTEND + "<=?", new String[] { // Selection args Long.valueOf(calendarId).toString(), calendarEventTitle, Long.toString(Config.CONFERENCE_START_MILLIS), Long.toString(Config.CONFERENCE_END_MILLIS) }, null); long newEventId = -1; if (cursor != null && cursor.moveToFirst()) { // Calendar event already exists for this session. newEventId = cursor.getLong(0); cursor.close(); // Data fix (workaround): batch.add(ContentProviderOperation.newUpdate(CalendarContract.Events.CONTENT_URI) .withValue(CalendarContract.Events.EVENT_TIMEZONE, Config.CONFERENCE_TIMEZONE.getID()) .withSelection(CalendarContract.Events._ID + "=?", new String[] { Long.valueOf(newEventId).toString() }) .build()); // End data fix. } else { // Calendar event doesn't exist, create it. // NOTE: we can't use batch processing here because we need the result of // the insert. values.clear(); values.put(CalendarContract.Events.DTSTART, sessionBlockStart); values.put(CalendarContract.Events.DTEND, sessionBlockEnd); values.put(CalendarContract.Events.EVENT_LOCATION, sessionRoom); values.put(CalendarContract.Events.TITLE, calendarEventTitle); values.put(CalendarContract.Events.CALENDAR_ID, calendarId); values.put(CalendarContract.Events.EVENT_TIMEZONE, Config.CONFERENCE_TIMEZONE.getID()); @SuppressWarnings("MissingPermission") Uri eventUri = resolver.insert(CalendarContract.Events.CONTENT_URI, values); String eventId = eventUri.getLastPathSegment(); if (eventId == null) { return batch; // Should be empty at this point } newEventId = Long.valueOf(eventId); // Since we're adding session reminder to system notification, we're not creating // Calendar event reminders. If we were to create Calendar event reminders, this // is how we would do it. //values.put(CalendarContract.Reminders.EVENT_ID, Integer.valueOf(eventId)); //values.put(CalendarContract.Reminders.MINUTES, 10); //values.put(CalendarContract.Reminders.METHOD, // CalendarContract.Reminders.METHOD_ALERT); // Or default? //cr.insert(CalendarContract.Reminders.CONTENT_URI, values); //values.clear(); } // Update the session in our own provider with the newly created calendar event ID. values.clear(); values.put(ScheduleContract.Sessions.SESSION_CAL_EVENT_ID, newEventId); resolver.update(sessionUri, values, null, null); } else { // Remove Calendar event, if exists. // Get the event calendar id. cursor = resolver.query(sessionUri, new String[] { ScheduleContract.Sessions.SESSION_CAL_EVENT_ID }, null, null, null); long calendarEventId = -1; if (cursor != null && cursor.moveToFirst()) { calendarEventId = cursor.getLong(0); cursor.close(); } // Try to remove the Calendar Event based on key. If successful, move on; // otherwise, remove the event based on Event title. int affectedRows = 0; if (calendarEventId != -1) { //noinspection MissingPermission affectedRows = resolver.delete(CalendarContract.Events.CONTENT_URI, CalendarContract.Events._ID + "=?", new String[] { Long.valueOf(calendarEventId).toString() }); } if (affectedRows == 0) { //noinspection MissingPermission resolver.delete(CalendarContract.Events.CONTENT_URI, String.format("%s=? and %s=? and %s=? and %s=?", CalendarContract.Events.CALENDAR_ID, CalendarContract.Events.TITLE, CalendarContract.Events.DTSTART, CalendarContract.Events.DTEND), new String[] { Long.valueOf(calendarId).toString(), calendarEventTitle, Long.valueOf(sessionBlockStart).toString(), Long.valueOf(sessionBlockEnd).toString() }); } // Remove the session and calendar event association. values.clear(); values.put(ScheduleContract.Sessions.SESSION_CAL_EVENT_ID, (Long) null); resolver.update(sessionUri, values, null, null); } return batch; } private interface SessionsQuery { String[] PROJECTION = { ScheduleContract.Sessions._ID, ScheduleContract.Sessions.SESSION_START, ScheduleContract.Sessions.SESSION_END, ScheduleContract.Sessions.SESSION_TITLE, ScheduleContract.Sessions.ROOM_NAME, ScheduleContract.Sessions.SESSION_IN_MY_SCHEDULE, }; int ROOM_NAME = 4; int SESSION_END = 2; int SESSION_IN_MY_SCHEDULE = 5; int SESSION_START = 1; int SESSION_TITLE = 3; int _ID = 0; } }