/// <summary>
/// Retrieves the next element from source.
/// </summary>
/// <param name="current">Current element</param>
/// <returns>The next element from items, if it exists. Otherwise, returns null</returns>
public async Task<EntitiesBase.RssSearchResult> Next(EntitiesBase.RssSearchResult current)
{
var data = await GetData();
if (current == null) return data.FirstOrDefault();
if (data.Any() && data.Last().Equals(current)) return null;
return data[data.IndexOf(current) + 1];
}
/// <summary>
/// Checks if data source has a element after the passed as parameter
/// </summary>
/// <param name="current">Current element</param>
/// <returns>True, if there is a next element, false if there is not</returns>
public async Task<bool> HasNext(EntitiesBase.RssSearchResult current)
{
var data = await GetData();
if (current == null || !data.Any()) return false;
return data.IndexOf(current) < data.Count - 1;
}
/// <summary>
/// Checks if data source has a element before the passed as parameter
/// </summary>
/// <param name="current">Current element</param>
/// <returns>True, if there is a previous element, false if there is not</returns>
public bool HasPrevious(EntitiesBase.RssSearchResult current)
{
var data = new List<EntitiesBase.RssSearchResult>();
if (current == null || !data.Any()) return false;
return data.IndexOf(current) > 0;
}
/// <summary>
/// Retrieves the previous element from source.
/// </summary>
/// <param name="current">Current element</param>
/// <returns>The previous element from items, if it exists. Otherwise, returns null</returns>
public EntitiesBase.YouTubeVideo Previous(EntitiesBase.YouTubeVideo current)
{
var data = new List<EntitiesBase.YouTubeVideo>();
if (current == null) return data.FirstOrDefault();
if (data.Any() && data.First().Equals(current)) return null;
return data[data.IndexOf(current) - 1];
}
/// <summary>
/// Checks if data source has a element before the passed as parameter
/// </summary>
/// <param name="current">Current element</param>
/// <returns>True, if there is a previous element, false if there is not</returns>
public bool HasPrevious(EntitiesBase.YouTubeVideo current)
{
var data = new List<EntitiesBase.YouTubeVideo>();
if (current == null || !data.Any()) return false;
return data.IndexOf(current) > 0;
}
/// <summary>
/// Retrieves the previous element from source.
/// </summary>
/// <param name="current">Current element</param>
/// <returns>The previous element from items, if it exists. Otherwise, returns null</returns>
public async Task<EntitiesBase.FlickrSearchResult> Previous(EntitiesBase.FlickrSearchResult current)
{
var data = await GetData();
if (current == null) return data.FirstOrDefault();
if (data.Any() && data.First().Equals(current)) return null;
return data[data.IndexOf(current) - 1];
}
