doodeec / lazylist

Android Lazy List

LazyList

Android Lazy List component

Version

1.0.0

Description

LazyList component for Android. ListView which supports lazy loading of resources (data), either synchronously (from memory, from local DB...) or asynchronously (HTTP, REST, ...).

Motivation is, that even when you have the data available in the memory, once you are porting it to listView adapter, it can get really slow to initialize the listView with large amount of data (200+ items). Speeding this process up is really easy with LazyList, because you can first initialize the adapter with only small amount of data, but later add all items as user will scroll the list down.

public class MovieListFragment extends LazyList<Movie> { ... }

public class MovieListAdapter extends LazyListAdapter<Movie> { ... }

Another case can be using a REST service to load the data. If you have a REST service which supports paging (you should have :) ) it is easy to override loadPage method to call REST service directly. Just define success/error callbacks and new data will automatically refresh the list.

@Override
protected synchronized void loadPage(final int page) {
    super.loadPage(page);

    ResourceService.loadMovies(page, new ServerResponseListener<Movie[]>() {
        @Override
        public void onSuccess(Movie[] movies) {
            if (movies.length > 0) {
                mData.addAll(Arrays.asList(movies));
                onDataLoadingCompleted(page);

                // save data to DB (handles create/update)
                MovieProvider.saveMoviesToDb(mData);
            } else {
                onDataLoadingFailed(REASON_LIST_END, null);
            }
        }

        @Override
        public void onError(ErrorResponse error) {
            onDataLoadingFailed(LazyList.REASON_SERVER_ERROR, page);
        }
        ...
    });
}

Usage

Just import com.doodeec.lazylist-X.Y.Z.aar into your project and override adapter and fragment to use desired types (you can look at the demo - Filmster project where it is used).

dependencies {
    compile(name:'com.doodeec.lazylist-1.0.0', ext:'aar')
    ...
}

Support

Supports generic types - you can extend both adapter and fragment to use any kind of data Supports Android SDK API10+ (2.3+)

Licence

released under Apache 2.0 licence

Demo

Check out Filmster project to see the demo project which fully takes advantage of LazyList library

Author

Dusan Bartos In case of any questions, do not hesitate to contact me - [e-mail]