ListBox鼠标悬停上的ListBoxItem索引

Question

I have a ListBox in a WPF application that has a MouseMove event handler attached. What I would like to do is to use this event to get the index of the item the mouse is over.

Simplified example of my code:

<StackPanel>
    <ListBox x:Name="MyList" MouseMove="OnMouseMove"/>
    <Separator/>
    <Button>Beep</Button>
</StackPanel>

public CodeBehindConstructor()
{
   List<string> list = new List<string>();
   list.Add("Hello");
   list.Add("World");
   list.Add("World"); //Added because my data does have duplicates like this

   MyList.ItemsSource = list;
}

public void OnMouseMove(object sender, MouseEventArgs e)
{
   //Code to find the item the mouse is over
}

Answer 1

I would try using ViusalHelper HitTest method for that, something like this :

private void listBox_MouseMove(object sender, MouseEventArgs e)
{
    var item = VisualTreeHelper.HitTest(listBox, Mouse.GetPosition(listBox)).VisualHit;

    // find ListViewItem (or null)
    while (item != null && !(item is ListBoxItem))
        item = VisualTreeHelper.GetParent(item);

    if (item != null)
    {
        int i = listBox.Items.IndexOf(((ListBoxItem)item).DataContext);
        label.Content = string.Format("I'm on item {0}", i);
    }

}

Answer 2

Try this:

public void OnMouseMove(object sender, MouseEventArgs e)
{
        int currentindex;
        var result = sender as ListBoxItem;

        for (int i = 0; i < lb.Items.Count; i++)
        {
            if ((MyList.Items[i] as ListBoxItem).Content.ToString().Equals(result.Content.ToString()))
            {
                currentindex = i;
                break;
            }
        }
}

You can also try this much shorter option:

public void OnMouseMove(object sender, MouseEventArgs e)
{
    int currentindex = MyList.Items.IndexOf(sender) ;
}

However I'm not too sure whether it will work with your method of binding.

A little hacky but you could get the point value of the current location and then use IndexFromPoint

Eg:

public void OnMouseMove(object sender, MouseEventArgs e)
{
    //Create a variable to hold the Point value of the current Location
    Point pt = new Point(e.Location);
    //Retrieve the index of the ListBox item at the current location. 
    int CurrentItemIndex = lstPosts.IndexFromPoint(pt);
}