RaisePropertyChanged가 UI를 업데이트하지 않습니다.

Question

ViewModel이 변경 될 때 UI를 올바르게 업데이트하기 위해 두 개의 목록 상자를 업데이트하는 데 문제가 있습니다.

첫 페이지 뒤의 기본 논리는 :

영화 제목을 가진 객체, 그리고 MovieDetails의 다양한입니다. MovieDetail은 자세한 내용은입니다. 더 중요한 것을 말하는 영광스러운 방법입니다. 나는 두 ListBoxes 영화가있는 경우이 MovieDetails으로는 'NotDetailed'에 대한ListBoxes, '상세'에 대한 하나 하나를 쌓아 구분하는 데 사용할 없음 '상세', 해당 목록은 BooleanToVisibilityConverter (반대의 경우도 마찬가지 통해 숨겨진되는 속성

나는 페이지로 이동)

, 나는 페이지에 해당하는 Movie을 설정하고 그것을 RaisePropertyChanged이 Movies.MovieDetailFetchedList을 다시 얻을해야 AllMoviesDetail ObservableCollection을 경고해야한다. 거기에서 AllMoviesDetail은 두 ObservableCollections (Detailed, NotDetailed)에 다시 get이어야한다고 알립니다.

실제로 RaisePropertyChanged (NotDetailedMovieDetails 또는 DetailedMovieDetails)은 아무 것도하지 않는 것으로 보입니다. (그리고 해당 해당 HasNotDetailedMovieDetails, Has...)

그러나 목록에 더 많은 항목을 추가하면 어떻게 작동합니까, CollectionChanged 이벤트를 발생시키고 목록을 다시 활성화 할 것입니다. 또한 (AllMoviesDetail 제외) var temp = DetailedMoviesDetail;

public class MoviesDetailViewModel : ViewModelBase 
{ 
    #region Property Names 

    public const string MoviePropertyString = "Movie"; 
    public const string AllMoviesDetailPropertyString = "AllMoviesDetail"; 
    public const string DetailedMoviesDetailPropertyString = "DetailedMoviesDetail"; 
    public const string NotDetailedMoviesDetailPropertyString = "NotDetailedMoviesDetail"; 
    public const string HasNotDetailedMoviesDetailPropertyString = "HasNotDetailedMoviesDetail"; 
    public const string HasDetailedMoviesDetailPropertyString = "HasDetailedMoviesDetail"; 
    public const string NotDetailedHeaderPropertyString = "NotDetailedHeader"; 

    #endregion 


    public MoviesDetailViewModel() 
    { 
     if (IsInDesignMode) 
     { 
      Movie = DesignDataStore.MovieList[0]; 
      Movie.Category = Category.DDA; 
     } 
    } 

    private Movie _Movie; 

    /// <summary> 
    /// The Movie for which to browse MoviesDetail. It is expected when setting this property, that MoviesDetail for it have been downloaded previously. 
    /// </summary> 
    /// <remarks>The 'Master' property for this ViewModel. All properties are Dependent on this and the underlying property MoviesDetailList</remarks> 
    /// <seealso cref="MovieDetailFetchedList"/> 
    public Movie Movie 
    { 
     get { return _Movie; } 
     set 
     { 
      if (_Movie != value) 
      { 
       if (_Movie != null) 
        _Movie.MovieDetailFetchedList.CollectionChanged -= MoviesDetailListChanged; 


       _Movie = value; 

       RaisePropertyChanged(MoviePropertyString); 
       RaisePropertyChanged(StatementPeriodAvailablePropertyString); 
       RaisePropertyChanged(NotDetailedMoviesDetailPropertyString); 
       Movie.MovieDetailFetchedList.CollectionChanged += MoviesDetailListChanged; 

       RaisePropertyChanged(AllMoviesDetailPropertyString); 

       RaisePropertyChanged(DetailedMoviesDetailPropertyString); 

       RaisePropertyChanged(NotDetailedHeaderPropertyString); 
      } 
     } 
    } 

    private void MoviesDetailListChanged(object sender, NotifyCollectionChangedEventArgs e) 
    { 
     if (e.Action == NotifyCollectionChangedAction.Add) 
     { 
      foreach (var item in e.NewItems) 
      { 
       if (((MovieDetail) item).IsDetailed()) 
        DetailedMoviesDetail.Add(item as MovieDetail); 
       else 
        NotDetailedMoviesDetail.Add(item as MovieDetail); 
      } 
     } 
     else 
     { 
      RaisePropertyChanged(AllMoviesDetailPropertyString); 
      RaisePropertyChanged(DetailedMoviesDetailPropertyString); 
      RaisePropertyChanged(NotDetailedMoviesDetailPropertyString); 
     } 
    } 




    #endregion 

    private MovieDetailFetchedList _allMoviesDetail; 
    public MovieDetailFetchedList AllMoviesDetail 
    { 
     get 
     { 
      if (Movie == null) 
       return new MovieDetailFetchedList(); 

      return _allMoviesDetail ?? (AllMoviesDetail = Movie.MovieDetailFetchedList); 
     } 
     set 
     { 
      if (_allMoviesDetail != value) 
      { 
       if (_allMoviesDetail != null) 
        _allMoviesDetail.CollectionChanged -= MoviesDetailListChanged; 
       _allMoviesDetail = value; 
       _allMoviesDetail.CollectionChanged += MoviesDetailListChanged; 

       RaisePropertyChanged(AllMoviesDetailPropertyString); 
       //force update 
       DetailedMoviesDetail = NotDetailedMoviesDetail = null; 
       RaisePropertyChanged(DetailedMoviesDetailPropertyString); 
       RaisePropertyChanged(HasDetailedMoviesDetailPropertyString); 
       RaisePropertyChanged(NotDetailedMoviesDetailPropertyString); 
       RaisePropertyChanged(HasNotDetailedMoviesDetailPropertyString); 
      } 

     } 
    } 

    public bool HasNotDetailedMoviesDetail { get { return NotDetailedMoviesDetail != null && NotDetailedMoviesDetail.Count > 0; } } 



    private ObservableCollection<MovieDetail> _notDetailedMoviesDetail; 
    public ObservableCollection<MovieDetail> NotDetailedMoviesDetail 
    { 
     get 
     { 
      if (Movie == null) return new ObservableCollection<MovieDetail>(); 

      return AllMoviesDetail; 
       return _notDetailedMoviesDetail ?? //make sure RaisePropertyChanged happens by using property setter 
       (NotDetailedMoviesDetail = AllMoviesDetail.Where(mem => !mem.IsDetailed()).ToObservableCollection()); 
     } 
     set 
     { 
      _notDetailedMoviesDetail = value; 
      RaisePropertyChanged(NotDetailedMoviesDetailPropertyString); 
      RaisePropertyChanged(HasNotDetailedMoviesDetailPropertyString); 
     } 
    } 

    public bool HasDetailedMoviesDetail 
    { get { return DetailedMoviesDetail != null && DetailedMoviesDetail.Count > 0; } } 

    private ObservableCollection<MovieDetail> _DetailedMoviesDetail; 
    public ObservableCollection<MovieDetail> DetailedMoviesDetail 
    { 
     get 
     { 
      if (Movie == null) return new ObservableCollection<MovieDetail>(); 

      return AllMoviesDetail; 
      return _DetailedMoviesDetail ?? //make sure RaisePropertyChanged happens by using property setter 
      (DetailedMoviesDetail = AllMoviesDetail.Where(mem => mem.IsDetailed()).ToObservableCollection()); 
     } 
     set 
     { 
      _DetailedMoviesDetail = value; 
      RaisePropertyChanged(DetailedMoviesDetailPropertyString); 
      RaisePropertyChanged(HasDetailedMoviesDetailPropertyString); 
     } 
    } 


    private string _DetailedHeader; 
    public string DetailedHeader 
    { 
     get { return _DetailedHeader ?? (_DetailedHeader = AppResources.in_available); } 
     set { _DetailedHeader = value; } 
    } 

    public string NotDetailedHeader 
    { 
     get { return (Movie != null && Movie.Category == Category.DRAMA) ? AppResources.Movie_MoviesDetail : AppResources.not_in_available; } 
    } 
} 

Answer 1

재산 게터의 모든 첫 번째 코드에 이 반환 문을 ObservableCollections을 한 인스턴스화하여이 작업을 수행 할 수 있었다. 첫 번째 만 실행되기 때문에 값이 할당되지 않고 PropertyChanged 이벤트가 트랩되지 않습니다.