uwp - UWP ListView Drop get index

Question

I have 2 ListViews, I can drag an item from ListView1 and drop it on to ListView2. If I drop the item between other items I want the item to be added in that same location.

So the question is: How do I get the position/index where I dropped my item?

I would expect to find the index somewhere in the DragEventArgs of the Drop event, but I can't find it anywhere:

private async void ListView2_Drop(object sender, DragEventArgs e)
{

}

标签： uwpdrag-and-drop

Answer 1

Anyway: I have tinkered around with this code and finally got it to work to my needs:

    private async void MyListView_Drop(object sender, DragEventArgs e)
    {
        var scrollViewer = VisualTreeHelper.GetChild(VisualTreeHelper.GetChild(MyListView, 0), 0) as ScrollViewer;
        var position = e.GetPosition((ListView)sender);
        var positionY = scrollViewer.VerticalOffset + position.Y;
        var index = GetItemIndex(positionY, MyListView);

        // do something useful with the index... 
    }

    int GetItemIndex(double positionY, ListView targetListView)
    {
        var index = 0;
        double height = 0;

        foreach (var item in targetListView.Items)
        {
            height += GetRowHeight(item, targetListView);
            if (height > positionY) return index;
            index++;
        }

        return index;
    }

    double GetRowHeight(object listItem, ListView targetListView)
    { 
        var listItemContainer = targetListView.ContainerFromItem(listItem) as ListViewItem;
        var height = listItemContainer.ActualHeight;
        var marginTop = listItemContainer.Margin.Top;
        return marginTop + height;
    }

Thank you for pointing me in the right direction!