I'm having a bit o' trouble...
Here is my "mappings.xml" file...
<?xml version="1.0" encoding="utf-8"?>
<mappings>
<mapping QID="info1">
<empty></empty>
</mapping>
<mapping QID="info2">
<empty></empty>
</mapping>
</mapping开发者_运维问答s>
My method that loads the XML and sets it as the ItemsSource for the listbox:
(Note: I didn't use<XMLDataProvider>
in XAML because it delivers a set of XML.XMLElement
, rather than the LINQ-Compatible XElement
I want to work with.
Private Property myCollectionView as CollectionView
Private Property mappingsEnum as IEnumerable(Of System.Xml.Linq.XElement)
Sub LoadXML()
mappingsEnum = XDocument.Load("mappings.xml").Root.Elements
'using collection view so I can apply
'filtering to the list of <mapping> objects
myCollectionView = CollectionViewSource.GetDefaultView(mappingsEnum)
myListBox.ItemsSource = myCollectionView
End Sub
in XAML
<Grid>
<ListBox x:Name="myListBox" ScrollViewer.VerticalScrollBarVisibility="Auto" DockPanel.Dock="Bottom" ScrollViewer.CanContentScroll="True" VirtualizingStackPanel.VirtualizationMode="Recycling" VirtualizingStackPanel.IsVirtualizing="True" SelectionMode="Extended">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid>
<!-- WHY DOESN'T THIS WORK?? -->
<TextBlock Text="{Binding XPath=@QID}">
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
I've tried setting the XPath to ".@QID" as well, that made no difference. I inspected the myListBox.Items
collection and confirmed the items are in fact XElement
objects that look like <mapping QID="..."><empty/></mapping>
so I don't think there is an issue there.
The end result is a listBox that fills with empty objects. I can filter them, sort them, and add non-bound text to them... but any binding to the source object is left unrendered.
http://msdn.microsoft.com/en-us/library/system.windows.data.binding.xpath.aspx
Some quote from there:
LINQ to XML objects XDocument and XElement do not use XPath. For details, see How to: Bind to XDocument, XElement, or LINQ for XML Query Results.
And some example how to bind to XElement
http://msdn.microsoft.com/en-us/library/cc165615.aspx
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