| Cancelable<T> | The interface for all the tasks that could be canceled. |
| DataSource | |
| MediaFeed.Listener | |
| MonitoredActivity.LifeCycleListener | |
| PopupMenu.Listener | |
| TimeBar.Listener | |
| VirtualFeed.RangeListener<E> |
| ImageManager.DataLocation | Enumerate type for the location of the images in gallery. |