Select item programmatically in WPF ListView

Question

I'm unable to figure out how to select an item programmatically in a ListView.

I'm attempting to use the listview's ItemContainerGenerator, but it just doesn't seem to work. For example, obj is null after the following operation:

//VariableList is derived from BindingList
m_VariableList = getVariableList();
lstVariable_Selected.ItemsSource = m_VariableList;
var obj = 
    lstVariable_Selected.ItemContainerGenerator.ContainerFromItem(m_VariableList[0]);

I've tried (based on suggestions seen here and other places) to use the ItemContainerGenerator's StatusChanged event, but to no avail. The event never fires. For example:

m_VariableList = getVariableList();
lstVariable_Selected.ItemContainerGenerator.StatusChanged += new EventHandler(ItemContainerGenerator_StatusChanged);
lstVariable_Selected.ItemsSource = m_VariableList;

...

void ItemContainerGenerator_StatusChanged(object sender, EventArgs e)
{
    //This code never gets called
    var obj = lstVariable_Selected.ItemContainerGenerator.ContainerFromItem(m_VariableList[0]);
}

The crux of this whole thing is that I simply want to pre-select a few of the items in my ListView.

In the interest of not leaving anything out, the ListView uses some templating and Drag/Drop functionality, so I'm including the XAML here. Essentially, this template makes each item a textbox with some text - and when any item is selected, the checkbox is checked. And each item also gets a little glyph underneath it to insert new items (and this all works fine):

<DataTemplate x:Key="ItemDataTemplate_Variable">
<StackPanel>
    <CheckBox x:Name="checkbox"
        Content="{Binding Path=ListBoxDisplayName}"
        IsChecked="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ListViewItem}}, Path=IsSelected}" />
    <Image ToolTip="Insert Custom Variable" Source="..\..\Resources\Arrow_Right.gif" 
        HorizontalAlignment="Left" 
        MouseLeftButtonDown="OnInsertCustomVariable"
        Cursor="Hand" Margin="1, 0, 0, 2" Uid="{Binding Path=CmiOrder}" />
</StackPanel>
</DataTemplate>

...

<ListView Name="lstVariable_All" MinWidth="300" Margin="5"
   SelectionMode="Multiple"
   ItemTemplate="{StaticResource ItemDataTemplate_Variable}"
   SelectionChanged="lstVariable_All_SelectionChanged"
   wpfui:DragDropHelper.IsDropTarget="True" 
   wpfui:DragDropHelper.IsDragSource="True"
   wpfui:DragDropHelper.DragDropTemplate="{StaticResource ItemDataTemplate_Variable}"
       wpfui:DragDropHelper.ItemDropped="OnItemDropped"/>

So what am I missing? How do I programmatically select one or more of the items in the ListView?

score 37 · Accepted Answer · edited Sep 27 '11 at 15:01

37

Bind the IsSelected property of the ListViewItem to a property on your model. Then, you need only work with your model rather than worrying about the intricacies of the UI, which includes potential hazards around container virtualization.

For example:

<ListView>
    <ListView.ItemContainerStyle>
        <Style TargetType="ListViewItem">
            <Setter Property="IsSelected" Value="{Binding IsGroovy}"/>
        </Style>
    </ListView.ItemContainerStyle>
</ListView>

Now, just work with your model's IsGroovy property to select/deselect items in the ListView.

edited Sep 27 '11 at 15:01

answered Jul 01 '09 at 15:12

Kent Boogaart

175,602
35
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393

2

But of course. Databinding. Don't all problems in WPF boil down at some point to databinding? Thanks, Kent. – Paul Prewett Jul 01 '09 at 15:52
This is a really neat solution, kudos! – Louis Kottmann Apr 22 '11 at 14:52
4

Just mention: this solution does not work on Windows Store app. Instead you should set the binding in code behind, like this:http://social.msdn.microsoft.com/Forums/windowsapps/en-US/9a0adf35-fdad-4419-9a34-a9dac052a2e3/listviewitemisselected-data-binding-in-style-setter-is-not-working?forum=winappswithcsharp – SimonFisher Dec 24 '13 at 15:02

Ahmad · Answer 2 · 2015-06-24T14:30:42.910

Where 'this' is the ListView instance. This will not only change the selection, but also set the focus on the newly selected item.

  private void MoveSelection(int level)
  {
     var newIndex = this.SelectedIndex + level;
     if (newIndex >= 0 && newIndex < this.Items.Count)
     {
        this.SelectedItem = this.Items[newIndex];
        this.UpdateLayout();
        ((ListViewItem)this.ItemContainerGenerator.ContainerFromIndex(newIndex)).Focus();
     }
  }

score 3 · Answer 3 · answered Jul 01 '09 at 15:06

Here would be my best guess, which would be a much simpler method for selection. Since I'm not sure what you're selecting on, here's a generic example:

var indices = new List<int>();

for(int i = 0; i < lstVariable_All.Items.Count; i++)
{
  // If this item meets our selection criteria 
  if( lstVariable_All.Items[i].Text.Contains("foo") )
    indices.Add(i);
}

// Reset the selection and add the new items.
lstVariable_All.SelectedIndices.Clear();

foreach(int index in indices)
{
  lstVariable_All.SelectedIndices.Add(index);
}

What I'm used to seeing is a settable SelectedItem, but I see you can't set or add to this, but hopefully this method works as a replacement.

score 1 · Answer 4 · answered Jul 23 '20 at 09:26

In case you are not working with Bindings, this could also be a solution, just find the items in the source and add them to the SelectedItems property of your listview:

 lstRoomLights.ItemsSource = RoomLights;
 var selectedItems = RoomLights.Where(rl => rl.Name.Contains("foo")).ToList();
 selectedItems.ForEach(i => lstRoomLights.SelectedItems.Add(i));

Select item programmatically in WPF ListView

4 Answers4

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