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我无法让我的用户界面更新两个Listboxes，以在我的ViewModel更改时正确更新。RaisePropertyChanged不更新UI
首先，页面背后的基本逻辑：
电影是具有标题的对象，以及各种MovieDetails。有些MovieDetail是比别人不同，因为它们是详细这是说他们是更重要的一个华而不实的方式。 我使用两个ListBoxes分离这些MovieDetails成堆叠ListBoxes，一个用于“详细”，一个用于“NotDetailed” 如果电影没有“详细”属性，相应列表经由BooleanToVisibilityConverter（反之亦然隐藏）
当我浏览网页，我设置了Movie页面对应，应该RaisePropertyChanged提醒AllMoviesDetailObservableCollection，它应该重新得到Movies.MovieDetailFetchedList。 从那里，AllMoviesDetail将提醒两个ObservableCollections (Detailed, NotDetailed)他们应该重新get。
实际上，NotDetailedMovieDetails或DetailedMovieDetails上的RaisePropertyChanged似乎也没有做任何事情。 （和相应的HasNotDetailedMovieDetails, Has...）
然而，如果我向列表中添加更多项目，CollectionChanged事件似乎会触发并重新激活列表，那么工作是什么。我还通过在代码第一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; }
}
}
感谢您的详细问题。不过，如果你能提供一个更小的代码样本来重现你的问题，它会更有帮助。在很多情况下，编写一个最小示例的过程将为您提供自己解决问题所需的洞察力。 – Dathan
还包括显示实现INotifyPropertyChanged的类的代码。 –