我如何从ListBoxItem的ControlTemplate获得控制权？

Question

Good day.

For ItemContainerStyle of ListBox I set my own style:

StyleClass.xaml

<Style x:Key="ItemContainerGalleryStyle" TargetType="{x:Type ListBoxItem}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type ListBoxItem}">
                <Grid x:Name="itemGrid">
                    ...
                </Grid>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<Style x:Key="ListBoxGalleryStyle2" TargetType="{x:Type ListBox}">
    <Setter Property="ItemContainerStyle" Value="{DynamicResource ItemContainerGalleryStyle}" />
</Style>

MainWindow.xaml

<Window ...>
<Window.Resources>
    <XmlDataProvider x:Key="GalleryXmlDataProvider"  Source="Gallery.xml"></XmlDataProvider>
</Window.Resources>
<Grid>        
    <ListBox x:Name="listBoxGallery" 
             Style="{StaticResource ListBoxGalleryStyle2}"                 
             ItemsSource="{Binding Mode=Default, 
                            Source={StaticResource GalleryXmlDataProvider}, 
                            XPath=/Gallery/Image}" />
    </Grid>
</Window>

In code I want to retrieve Grid Control of my selected item. I attempt to do it by means of a listBoxGallery.Template.FindName . But I can't get at how to use this method.

How can I extract Grid from ControlTemplate?

Answer 1

You are trying to get an element from ListBoxItem's template and not from ListBox. So you need to get the exact ListBoxItem, before you using accessing its template. In below code snippet, I shown you how to get item from 0th element and taking the Grid from its template.

var container = listBoxGallery.ItemContainerGenerator.ContainerFromIndex(0) as ListBoxItem;
var iremgrid = container.Template.FindName("itemGrid") as Grid;