title: What exactly gets executed on Android device when you check Settings > Accounts > Google account > Sync Calendar?
body: <p>On Android device, when you go to Settings > Accounts > your Google account > and check Sync Calendar, what exactly gets executed?</p>
  
  <p>I suppose there must be something like a built in sync adapter which connects to the Google Calendar server, gets the necessary changes and updates local Calendar Provider tables. Is there any way to use this functionality rather than implement my own calendar sync adapter (which does not look like a trivial task at all) to keep Calendar Provider tables synced?</p>
  
  <p>If it is not possible, is there any sample of <code>onPerformSync()</code> <strong>calendar-specific</strong> implementation?</p>
  
  <p>To be clear: I know how to write, configure and use a service, sync adapter, content observer, <code>ContentResolver.requestSync()</code> etc. What is still unclear to me is how to implement specific <code>onPerformSync()</code>to sync Google Calendar and whether I really have to write my own implementation for it.</p>