我将对象 OptionSelector 传递给不同的 ViewModel。通过时它不为空。但在接收端它显示为空。有任何想法吗
我的视图包含在这个类中。
public class CoreView : XboxApplicationPage, IRefAppNavigationItem
{
/// <summary>
/// Gets or sets navigation data for nested views.
/// </summary>
public object Data
{
get { return GetValue(DataProperty) as object; }
set { SetValue(DataProperty, value); }
}
/// <summary>
/// Identifies the Data dependency property.
/// </summary>
public static readonly DependencyProperty DataProperty =
DependencyProperty.Register("Data",typeof(object),typeof(CoreView),new PropertyMetadata(null));
/// <summary>
/// Gets or sets the viewModel used in this page.
/// </summary>
public CoreViewModel ViewModel
{
get
{
return (CoreViewModel)GetValue(ViewModelProperty);
}
set { SetValue(ViewModelProperty, value); }
}
/// <summary>
/// Sets the View.DataContext to the View.ViewModel.
/// </summary>
private void SetViewModel()
{
if (ViewModel != null)
{
try
{
if (this.Data != null)
{
ViewModel.Data = this.Data;
}
else
{
ViewModel.Data = this.Tag;
}
SetDataContext();
}
catch(Exception e)
{
Logger.Log("SetViewModel() error :" + e.StackTrace);
}
}
}
/// <summary>
/// Sets the DataContext to the ViewModel.
/// Override when additional actions might be required after setting the DataContext.
/// </summary>
protected virtual void SetDataContext()
{
this.DataContext = ViewModel;
}
/// <summary>
/// Handles on NavigateTo events.
/// </summary>
/// <param name="e">Event args.</param>
/// <remarks>This method is used to get the post navigation data and integrate into CoreView.</remarks>
protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{
if (DesignerProperties.IsInDesignTool)
{
return;
}
try
{
if (this.currentPageCulture != AmebaTV_XBOXApplication.Common.Resources.Localization.CurrentCulture)
{
UpdateLocalizedStrings(this);
}
Microsoft.Xbox.Controls.Localization.CultureChanged += Localization_CultureChanged;
var postNavigationState = IoC.Get<INavigationService>().GetPostNavigationData(NavigationContext);
if (postNavigationState != null)
{
this.Data = postNavigationState;
}
this.ViewModel.OnNavigatedTo();
if (legendService != null)
{
legendService.IsNavigateBackEnabled = true;
}
base.OnNavigatedTo(e);
}
catch (Exception ex)
{
Logger.Log("OnNavigatedTo : "+ex.Message);
}
}
}
/// <summary>
/// Base class for all ViewModels.
/// </summary>
public class CoreViewModel : ViewModelBase
{
/// <summary>
/// Field for Data.
/// </summary>
private object data;
/// <summary>
/// To be used with navigation to populate view models with initial content.
/// </summary>
public virtual void OnDataSet()
{
}
/// <summary>
/// Gets or sets ViewModel data.
/// </summary>
public object Data
{
get { return this.data; }
set
{
this.data = value;
RaisePropertyChanged("Data");
OnDataSet();
}
}
}
OptionSelectorData 对象
/// <summary>
/// Contains data for the options selector view.
/// </summary>
public class OptionSelectorData
{
/// <summary>
/// Gets or sets the list of options.
/// </summary>
public IList<string> Options { get; set; }
/// <summary>
/// Gets or sets the option title.
/// </summary>
public string Title { get; set; }
/// <summary>
/// Gets or sets the callback that will be invoked when an option is selected
/// </summary>
public Action<string> NotificationCallback { get; set; }
}
}
触发导航的命令
public class MoreOverflowViewModel : CoreViewModel
{
/// <summary>
/// Navigate to Property filter page
/// </summary>
public ICommand gotoViewPagebyCriteria
{
get
{
return new RelayCommand(() =>
{
OptionSelectorData option = new OptionSelectorData
{
Options = filterOptions, Title =
Localization.GetByLocalizationKey("OptionTitleFilter"),
NotificationCallback = OnFilterOptionsCallback
};
Messenger.Default.Send(new NavigateToMessage(new
Uri(PageListings.ViewPageByCriteria, UriKind.Relative), option));
});
}
}
}
Viewmodel 接收数据，OnDataSet 检查对象并设置属性
public class ViewByCriteriaViewModel : CoreViewModel
{
/// <summary>
/// ondataset
/// </summary>
public override void OnDataSet()
{
option = this.Data as OptionSelectorData;
if (option != null)
{
OptionTitle = option.Title;
itemsSource = option.Options;
}
else
{
Logger.Log("NULL Option Data");
}
}
}