项目概况
我有一个视图绑定到包含 2 ObserverableCollection 的视图模型。viewmodel 构造函数填充第一个 ObserverableCollection 并收集视图数据上下文以通过名为 Sites 的公共属性绑定到它。
稍后在 LoadOrders 方法中填充 2ed ObserverableCollection，并更新公共属性 LoadFraudResults 以将其与 datacontext 绑定。
我正在使用 WCF 从数据库中提取数据，并且非常好地提取数据。
查看模型源
class ManageFraudOrderViewModel:ViewModelBase
{
#region Fields
private readonly ICollectionView collectionViewSites;
private readonly ICollectionView collectionView;
private ObservableCollection<GeneralAdminService.Website> _sites;
private ObservableCollection<FraudService.OrderQueue> _LoadFraudResults;
#endregion
#region Properties
public ObservableCollection<GeneralAdminService.Website> Sites
{
get { return this._sites; }
}
public ObservableCollection<FraudService.OrderQueue> LoadFraudResults
{
get { return this._LoadFraudResults;}
}
#endregion
public ManageFraudOrderViewModel()
{
//Get values from wfc service model
GeneralAdminService.GeneralAdminServiceClient generalAdminServiceClient = new GeneralAdminServiceClient();
GeneralAdminService.Website[] websites = generalAdminServiceClient.GetWebsites();
//Get values from wfc service model
if (websites.Length > 0)
{
_sites = new ObservableCollection<Wqn.Administration.UI.GeneralAdminService.Website>();
foreach (GeneralAdminService.Website website in websites)
{
_sites.Add((Wqn.Administration.UI.GeneralAdminService.Website)website);
}
this.collectionViewSites= CollectionViewSource.GetDefaultView(this._sites);
}
generalAdminServiceClient.Close();
}
public void LoadOrders(Wqn.Administration.UI.FraudService.Website website)
{
//Get values from wfc service model
FraudServiceClient fraudServiceClient = new FraudServiceClient();
FraudService.OrderQueue[] OrderQueue = fraudServiceClient.GetFraudOrders(website);
//Get values from wfc service model
if (OrderQueue.Length > 0)
{
_LoadFraudResults = new ObservableCollection<Wqn.Administration.UI.FraudService.OrderQueue>();
foreach (FraudService.OrderQueue orderQueue in OrderQueue)
{
_LoadFraudResults.Add(orderQueue);
}
}
this.collectionViewSites= CollectionViewSource.GetDefaultView(this._LoadFraudResults);
fraudServiceClient.Close();
}
}
查看源
公共部分类 OrderQueueControl : UserControl {
private ManageFraudOrderViewModel manageFraudOrderViewModel ;
private OrderQueue orderQueue;
private ButtonAction ButtonAction;
private DispatcherTimer dispatcherTimer;
public OrderQueueControl()
{
LoadOrderQueueForm();
}
#region LoadOrderQueueForm
private void LoadOrderQueueForm()
{
//for binding the first observablecollection
manageFraudOrderViewModel = new ManageFraudOrderViewModel();
this.DataContext = manageFraudOrderViewModel;
}
#endregion
private void cmbWebsite_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
BindItemsSource();
}
#region BindItemsSource
private void BindItemsSource()
{
using (OverrideCursor cursor = new OverrideCursor(Cursors.Wait))
{
if (!string.IsNullOrEmpty(Convert.ToString(cmbWebsite.SelectedItem)))
{
Wqn.Administration.UI.FraudService.Website website = (Wqn.Administration.UI.FraudService.Website)Enum.Parse(typeof(Wqn.Administration.UI.FraudService.Website),cmbWebsite.SelectedItem.ToString());
//for binding the second observablecollection*******
manageFraudOrderViewModel.LoadOrders(website);
this.DataContext = manageFraudOrderViewModel;
//for binding the second observablecollection*******
}
}
}
#endregion
}
XAML
ComboBox x:Name="cmbWebsite" ItemsSource="{Binding Sites}" Margin="5"
Width="100" Height="25" SelectionChanged="cmbWebsite_SelectionChanged"
DataGrid ItemsSource ={Binding Path = LoadFraudResults}
问题领域：
当我调用 LoadOrderQueueForm 绑定第一个 observablecollection 和后来的 BindItemsSource 绑定 2ed observable 集合时，一切正常，第一次绑定没有问题。
但是，当我再次调用 BindItemsSource 以通过 cmbWebsite_SelectionChanged 根据更改的选定组合值重新填充 obseravablecollection 时，observalblecollection 将填充新值，并且 viewmodule 中的 LoadFraudResults 属性填充有新值；但是当我调用数据上下文重新绑定数据网格时，数据网格不会反映更改的值。
换句话说，当在视图的 BindItemsSource 方法中调用数据上下文时，数据网格不会更改。
manageFraudOrderViewModel.LoadOrders(website);
this.DataContext = manageFraudOrderViewModel;
manageFraudOrderViewModel 值是正确的，但数据网格未反映更改的值。
请帮忙，因为我在过去 2 天里一直被这件事困住，而且截止日期快到了。
提前致谢