CollectionViewSource bind source to webservice (using WCF RIA services and LINQ) - Silverlight

问题

I have a small problem, probably stupid but I can't figure this out.. Anyways all I'm trying to do is bind my CollectionViewSource.Source to my resulting query in Silverlight 4 with WCF RIA services.

This is my XAML :

<UserControl.Resources>
    <CollectionViewSource x:Name="cvsServiceTypes" />
</UserControl.Resources>
<Grid>
    <ComboBox Height="23" HorizontalAlignment="Left" ItemsSource="cvsServiceTypes" DisplayMemberPath="Type" SelectedValuePath="IDServicesType" Margin="154,51,0,0" Name="cbServiceType" VerticalAlignment="Top" Width="120" SelectedValue="{Binding fkservicetype, Mode=TwoWay}" />
</Grid>

And my CodeBehind :

  public Services()
  {
      InitializeComponent();

      webService.GetServiceTypesCompleted += (s, e) => { cvsServiceTypes.Source = e.Result; };
      webService.GetServiceTypesAsync();
   }

But it doesn't seem to work... what am I doing wrong?

Thank you very much!

回答1:

I hope you don't mind if I ignore the web service call part - it looks like you're struggling with binding your items to the ComboBox, so that's the part I'll address.

You need to do the following:

Create an ObservableCollection property to contain your items.
Bind the CollectionViewSource.Source to the ObservableCollection.
Bind the ComboBox.ItemsSource to the CollectionViewSource.
Set the DataContext on your UserControl.

Here is an example:

<UserControl ...>
    <StackPanel>
        <StackPanel.Resources>
            <CollectionViewSource x:Key="cvs" Source="{Binding Path=Items}"></CollectionViewSource>
        </StackPanel.Resources>
        <ComboBox ItemsSource="{Binding Source={StaticResource ResourceKey=cvs}}" />
        <ComboBox ItemsSource="{Binding Source={StaticResource ResourceKey=cvs}}" />
        <ComboBox ItemsSource="{Binding Source={StaticResource ResourceKey=cvs}}" />
    </StackPanel>
</UserControl>

The code:

public partial class UserControl1 : UserControl
{
    public UserControl1()
    {
        InitializeComponent();
        this.DataContext = this;
        _items.Add("a");
        _items.Add("b");
    }

    private ObservableCollection<string> _items = new ObservableCollection<string>();
    public ObservableCollection<string> Items
    {
        get { return _items; }
        set { _items = value; }
    }
}

You can put items into the collection when your web service call completes like this:

webService.GetServiceTypesCompleted += (s, e) => 
{
    foreach (string s in e.result)
    {
        _items.Add(s);
    }
};

来源：https://stackoverflow.com/questions/5589017/collectionviewsource-bind-source-to-webservice-using-wcf-ria-services-and-linq

标签

silverlight

wcf

web-services