public CachingSongFetcher(ISongFetcher <T> wrappedFetcher, IBlobCache cache, string cacheKey, TimeSpan cacheDuration)
{
if (wrappedFetcher == null)
{
throw new ArgumentNullException("wrappedFetcher");
}
if (cache == null)
{
throw new ArgumentNullException();
}
if (String.IsNullOrWhiteSpace(cacheKey))
{
throw new ArgumentException("Cache key can't be null or empty", "cacheKey");
}
if (cacheDuration < TimeSpan.Zero)
{
throw new ArgumentOutOfRangeException("cacheDuration");
}
this.wrappedFetcher = wrappedFetcher;
this.cache = cache;
this.cacheKey = cacheKey;
this.cacheDuration = cacheDuration;
}
public ArtistsViewModel(ISongFetcher <T> songFetcher, string serializationKey)
{
if (songFetcher == null)
{
throw new ArgumentNullException("songFetcher");
}
this.Activator = new ViewModelActivator();
this.WhenActivated(() =>
{
var disposable = new CompositeDisposable();
this.LoadCommand = ReactiveCommand.CreateAsyncObservable(_ => songFetcher.GetSongsAsync()
.Timeout(LoadCommandTimeout, RxApp.TaskpoolScheduler)
.TakeUntil(disposable));
this.artists = this.LoadCommand
.Do(x => this.songs = x)
.Select(GetArtists)
.ToProperty(this, x => x.Artists, new List <string>());
this.WhenAnyValue(x => x.SelectedArtist).Where(x => x != null)
.Select(FilterSongsByArtist)
.Select(x => BlobCache.LocalMachine.InsertObject(serializationKey, x))
.Concat()
.Subscribe();
return(disposable);
});
}
public RemoteArtistsViewModel(ISongFetcher <NetworkSong> songFetcher = null, IBlobCache cache = null)
: base(new CachingSongFetcher <NetworkSong>(songFetcher ?? new RemoteSongFetcher(), cache ?? BlobCache.LocalMachine, BlobCacheKeys.RemoteSongs, CacheDuration), BlobCacheKeys.SelectedRemoteSongs)
{
}
