Silverlight 4 and LisBox's SelectedItem when using DataTemplate as ItemTemplate
I'm using tow listboxes for drag n drop where user can drag items from source listbox and drop on the target. I'm using a DataTemplate for the ListBoxItems of my ListBox Controls.
I need to give the user ability to move up/down items in the target listbox after they been moved from source. I have two button "Move Up" & "Move Down" to do that but when the user clicks on one of the button, it returns me the null object as selectedItem.
here is my code
private void moveUp_Click(object sender, RoutedEventArgs e)
{
ListBoxItem selectedItem = lstmenuItems.SelectedItem as ListBoxItem;
if (selectedItem != null)
{
int index = lstmenuItems.Items.IndexOf(selectedItem);
if (index != 0)
{
lstmenuItems.Items.RemoveAt(index);
index -= 1;
lstmenuItems.Items.Insert(index, selectedItem);
lstmenuItems.SelectedIndex = index;
}
}
}
I'm sure its to do with the ItemTemplate. here is the xaml for listbox
<ListBox x:Name="lstmenuItems" Height="300" MinWidth="200" >
<ListBox.ItemTemplate>
<DataTemplate>
<StackPan开发者_开发知识库el Orientation="Horizontal">
<StackPanel Orientation="Vertical">
<TextBlock Text="{Binding Code}"/>
<TextBlock Text="{Binding RetailPrice, StringFormat=£\{0:n\}}" />
</StackPanel>
<!-- Product Title-->
<TextBlock Text="{Binding Description1}" Width="100" Margin="2" />
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
Any ideas how can I access the selected Item and how can I move it up/down?
Thanks in advance
The selectedItem
variable will contain a null because the SelectedItem
property doesn't return the type ListBoxItem
. The SelectedItem
property returns an object it received from the collection supply its ItemsSource
property.
Change to :-
object selectedItem = lstmenuItems.SelectedItem;
and that should get you a little further.
That said consider having the ItemsSource
bound to an ObservableCollection
and manipulate the collection instead.
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