Get coordinates within listview when scrolled down

Question

I would like to get the 'real' Y-value of the point i clicked on when scrolled down a listview.

Here is the XAML:

<Window x:Class="MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" MaxHeight="350" MinHeight="350" Width="525">
<Grid>
    <ListView Name="MyListView" ScrollViewer.CanContentScroll="True" ScrollViewer.VerticalScrollBarVisibility="Auto">
    </ListView>
</Grid>
</Window>

and here the code:

Class MainWindow 
Sub New()
    InitializeComponent()
    For i As Integer = 0 To 100
        MyListView.Items.Add(i)
    Next
End Sub
Private Sub MyListView_MouseLeftButtonUp(sender As Object, e As MouseButtonEventArgs) Handles MyListView.MouseLeftButtonUp
    MsgBox(e.GetPosition(MyListView).Y)
End Sub
End Class

My problem now is that no matter how far down I scrolled, the top is always 1 and the bottom is always 309, but when scrolled down i would like to get values higher than 309. Is there any way to find out the 'real' Y-coordinate I clicked on or maybe find out how far down I scrolled and then being able to calculate the adjusted value? Wrapping the listview in a scrollviewer control is not an option btw.

Thanks for any answers

Welcome to Staock Overflow. Your question is well written, but you can improve things by adding tags that describe the languages relevant to the question — GreenAsJade, Jan 29 '14 at 08:28
Hopefully someone will be along who can actually answer the question. I'm not a vb.net person, but generally I would expect the answer to this question to entail asking the scroller how far it is scrolled. Maybe that is something to look into... — GreenAsJade, Jan 29 '14 at 09:08
This was my first idea, but I got no Idea how to access the built in ScrollViewer of the ListView. I do not want to wrap an extra scrollviewer around the control. Solutions in vb.net or C# appreciated. — Isildur, Jan 29 '14 at 09:26
http://stackoverflow.com/questions/1851620/handling-scroll-event-on-listview-in-c-sharp — GreenAsJade, Jan 29 '14 at 09:46
Thanks, the link helped. By calling Media.VisualTreeHelper.GetChild(Mylistview,0).Child I got the Scrollviewer and apparently Scrollviewer.VerticalOffset gives me the amount of Items Scrolled down and that is exactly what I needed. — Isildur, Jan 29 '14 at 12:58
Yay. I summarised our finding in an answer - if you would be kind enough to accept (or critique) that would be great. — GreenAsJade, Jan 29 '14 at 13:13

score 0 · Accepted Answer · edited Jan 30 '14 at 09:47

In order to determine the real Y value, you need to know the amount that has been scrolled, which the scrollviewer can tell you.

You can obtain the scrollviewer as a child of the listview (Media.VisualTreeHelper.GetChild(Mylistview,0).Child) , and from there the vertical offset it currently has (Scrollviewer.VerticalOffset). The vertical Offset does not give you the the y-coordinate-offset, instead you get the amount of listview-items scrolled down. You can easily work with that.

Get coordinates within listview when scrolled down

1 Answers1