Implement 'Delete Item' command for multiple ListView controls - wpf

Question

I have multiple ListViews in an MVVM WPF application, backed by ObservableCollections.
I'm implementing a "Delete Item" context menu item for each ListView. Currently I have the SelectedItem for each ListView bound to the same object in my ViewModel. However to delete the item from the ObservableCollection requires the name of the ListView (in this case Wk01CECollection):
private void DeleteLO()
{
this.Wk01CECollection.Remove(SelectedCE);
}
Is there a way to reference the ListView that the SelectedItem is a member of? As it is I'll need to wire up a separate delete method for each ListView.

Answer 1

I'm sure this is not the "best practice" way to achieve this, but it's quite simple:
You could pass the ListView's selected item as a parameter to the command:
<Button Content="Delete selected item" Command="{Binding DeleteCommand}" CommandParamenter="{Binding ElementName=SomeListView, Path=SelecteItem}" />
Since you can try to remove an item from an ObservableCollection even if it does not exist in the collection without getting an exception, in your private Delete method you can try to remove that item from all the ObservableCollections you have in your ViewModel. I'm assuming here that an item cannot be in two collections at the same time, if this is not the case, what I said won't work because you'll remove the item from all your collections. If you plan to do this, just check for null before removing, if you try to remove a null object you'll get an exception.
private void DeleteLO(object listitem)
{
if(listitem != null)
{
if(listitem as CollectionType1 != null) //cast your listitem to the appropiate type inside your collection
this.Wk01CECollection.Remove(listitem);
if(listitem as CollectionType2 != null)
this.Wk02CECollection.Remove(listitem);
//etc.
}
}
Besides all of this, if you are using MVVM it is best that the ViewModel does not know about the View, so referencing the ListView inside the VM would break that principle.

Answer 2

I understand the issue is long gone, but will post for googlers.
This worked for me:
private void LvPrevKeyDown(object sender, KeyEventArgs e)
{
//Nothing to do here
if (Lv.SelectedItems.Count == 0) return;
//Empty space for other key combinations
//Let's remove items. If it's a simple delete key so we'll remove just the selected items.
if (e.Key != Key.Delete || Keyboard.Modifiers != ModifierKeys.None) return;
var tmp = Lv.SelectedItems.Cast<ColorItem>().ToList();
foreach (var colorItem in tmp)
{
_cList.Remove(colorItem);
}
}
Nothing fancy in the xaml. Just some columns bound to _cList properties and items source bound to _cList, of course.
Hope it'll help someone!
Kind regards!