增量集合爲Silverlight加載/ ISupportIncrementalLoading

Question

您是否知道增量集合的備選加載方式，如wpf ISupportIncrementalLoading？

Answer 1

，我看到沒有任何答案;（ 對於原因，我將張貼在這裏我實現 庫仍處於BETA版本，並請，如果您有任何問題請點擊這裏發送您的問題

/// P.Zh. 
public class IncrementalLoadingCollection<T, TT> : ObservableCollection<TT>, ISupportIncrementalLoading 
    where T : IIncrementalSource<TT>, new() 
    { 
     private T source; 
     private int itemsPerPage; 
     private bool hasMoreItems; 
     private int currentPage; 

     public IncrementalLoadingCollection(int itemsPerPage = 20) 
     { 
      this.source = new T(); 
      this.itemsPerPage = itemsPerPage; 
      this.hasMoreItems = true; 
     } 

     public bool HasMoreItems 
     { 
      get { return hasMoreItems; } 
     } 

     public async Task<LoadMoreItemsResult> LoadMoreItemsAsync(uint count) 
     { 
      var task = Task.Factory.StartNew(async() => 
      { 
       uint resultCount = 0; 
       var result = await source.GetPagedItems(null, currentPage++, itemsPerPage); 
       if (result == null || result.Count() == 0) 
       { 
        hasMoreItems = false; 
       } 
       else 
       { 
        resultCount = (uint)result.Count(); 
        Deployment.Current.Dispatcher.BeginInvoke(() => 
        { 
         foreach (TT item in result) 
          this.Add(item); 
        }); 
       } 
       return new LoadMoreItemsResult() { Count = resultCount }; 
      } 
      // ,CancellationToken.None, TaskCreationOptions.None, TaskScheduler.Default    
      ).Unwrap();   
      return task.Result; 
     }  
    } 

    public interface IIncrementalSource<T> 
    { 
     /// <summary> 
     /// Get Chunk of data in specific interval from a colection 
     /// </summary> 
     /// <param name="o">custome object</param> 
     /// <param name="pageIndex">uint start position</param> 
     /// <param name="pageSize">uint end position</param> 
     /// <returns>Result is chunk</returns> 
     Task<IEnumerable<T>> GetPagedItems(object o, int pageIndex, int pageSize); 
     bool HasMoreItems { get; set; } 
    } 

    public interface ISupportIncrementalLoading 
    { 
     bool HasMoreItems { get; } 
     Task<LoadMoreItemsResult> LoadMoreItemsAsync(uint count); 
    } 

    public interface IIncrementalResult<T> 
    { 
     IEnumerable<T> Items { get; } 
     int VirtualCount { get; } 
    } 

    public struct LoadMoreItemsResult 
    { 
     public uint Count { get; set; } 
    } 

。