diff options
Diffstat (limited to 'android/arch/paging/LivePagedListBuilder.java')
| -rw-r--r-- | android/arch/paging/LivePagedListBuilder.java | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/android/arch/paging/LivePagedListBuilder.java b/android/arch/paging/LivePagedListBuilder.java index b0fddba2..f2d09cc7 100644 --- a/android/arch/paging/LivePagedListBuilder.java +++ b/android/arch/paging/LivePagedListBuilder.java @@ -88,9 +88,21 @@ public class LivePagedListBuilder<Key, Value> { } /** - * Sets a {@link PagedList.BoundaryCallback} on each PagedList created. + * Sets a {@link PagedList.BoundaryCallback} on each PagedList created, typically used to load + * additional data from network when paging from local storage. * <p> - * This can be used to + * Pass a BoundaryCallback to listen to when the PagedList runs out of data to load. If this + * method is not called, or {@code null} is passed, you will not be notified when each + * DataSource runs out of data to provide to its PagedList. + * <p> + * If you are paging from a DataSource.Factory backed by local storage, you can set a + * BoundaryCallback to know when there is no more information to page from local storage. + * This is useful to page from the network when local storage is a cache of network data. + * <p> + * Note that when using a BoundaryCallback with a {@code LiveData<PagedList>}, method calls + * on the callback may be dispatched multiple times - one for each PagedList/DataSource + * pair. If loading network data from a BoundaryCallback, you should prevent multiple + * dispatches of the same method from triggering multiple simultaneous network loads. * * @param boundaryCallback The boundary callback for listening to PagedList load state. * @return this @@ -106,6 +118,8 @@ public class LivePagedListBuilder<Key, Value> { /** * Sets executor which will be used for background loading of pages. * <p> + * If not set, defaults to the Arch components I/O thread. + * <p> * Does not affect initial load, which will be always be done on done on the Arch components * I/O thread. * |