wpf combobox数据绑定xml

Question

I want to display all groupnames (contact_grname) into my combobox, but only one item is showing up ! Why is that ?!

<XmlDataProvider x:Key="TeleData" XPath="/response/contacts/contact">

</XmlDataProvider>

<CollectionViewSource x:Key="TeleView"  Source="{StaticResource TeleData}" >
    <CollectionViewSource.SortDescriptions>
        <scm:SortDescription PropertyName="contact_name" Direction="Ascending" />

    </CollectionViewSource.SortDescriptions>

    <CollectionViewSource.GroupDescriptions>
        <dat:PropertyGroupDescription PropertyName="contact_grname" />

    </CollectionViewSource.GroupDescriptions>
</CollectionViewSource>

<ComboBox ItemsSource="{Binding Source={StaticResource TeleView}, XPath=contact_grname}" />

my xml file:

<?xml version="1.0" encoding="ISO-8859-1"?>
<response>
    <contacts>
        <contact>
            <contact_grname>group1</contact_grname>
            <contact_name>Bart</contact_name>
        </contact>
        <contact>
            <contact_grname>group1</contact_grname>
            <contact_name>Eric</contact_name>
        </contact>
        <contact>
            <contact_grname>group2</contact_grname>
            <contact_name>Mike</contact_name>
        </contact>
    </contacts>
</response>

Just group1 is showing up (one time). When I use StaticResource TeleData instead of TeleView in combobox, then all groupnames are displayed (but there are doubles values because not grouped that way)

Expected output in combobox:

• group1
• group2

Now I have (with TeleView):

• group1

and if I use Teledata:

• group1
• group1
• group2

Answer 1

This is not the answer to your question, but it might help. Consider this ComboBox:

<ComboBox SelectedIndex="1">
        <ComboBox.Resources>
            <XmlDataProvider x:Key="Data"
                             XPath="response/contacts">
                <x:XData>
                        <response>
                            <contacts>
                                <contact>
                                    <contact_grname>group1</contact_grname>
                                    <contact_name>Bart</contact_name>
                                    <contact_name>Eric</contact_name>
                                </contact>
                                <contact>
                                    <contact_grname>group2</contact_grname>
                                    <contact_name>Mike</contact_name>
                                </contact>
                            </contacts>
                        </response>
                </x:XData>
            </XmlDataProvider>
        </ComboBox.Resources>
        <ComboBox.ItemsSource>
            <Binding Source="{StaticResource Data}"
                     XPath="contact/contact_name"  />
        </ComboBox.ItemsSource>
    </ComboBox>

It shows "Bart", "Eric" and "Mike". With this binding:

<Binding Source="{StaticResource Data}"
                     XPath="contact/contact_grname"  />

You will get "group1","group2". But this is because I changed xml. With your xlm, I mean with this:

 <contact>
    <contact_grname>group1</contact_grname>
    <contact_name>Bart</contact_name>
 </contact> 
 <contact>
    <contact_grname>group1</contact_grname>
    <contact_name>Mike</contact_name>
 </contact> 

the result is "group1","group1" and "group2".

So, One suggestion is to remove /contact from this line of code:

<XmlDataProvider x:Key="TeleData" XPath="/response/contacts/contact">

Answer 2

If you just want to display the Groups you can actually access the CollectionViewSource.View.Groups property via the ItemSource path

<ComboBox ItemsSource="{Binding Source={StaticResource TeleView}, Path=Groups}" SelectedValuePath="Name" />

Output:

• group1
• group2