ListView Scroll Event

[Urs Vogel]

Hi

I'm looking for a way to trap the ListView's scroll events, in order to
control page-wise loading of not bindable data. Any hints of how to achieve
this?

Thanks, Urs

[Robin Tucker]

Re: ListView Scroll Event

What you want is a "virtual list view". I don't see ListView as
particularly viable for this (I have tried it before). In the end I wrote
my own control which does the same and allows me to owner draw each row
(including images in cells).


"Urs Vogel" <uvogel@msn.com > wrote in message
news:umwGzz2DFH A.208@TK2MSFTNG P12.phx.gbl...[color=blue]
> Hi
>
> I'm looking for a way to trap the ListView's scroll events, in order to
> control page-wise loading of not bindable data. Any hints of how to
> achieve this?
>
> Thanks, Urs
>[/color]

[Urs Vogel]

Re: ListView Scroll Event

Thanks Robin

I'll inherit ListView and attach my own vertical scroll bar, using some API
calls to achieve some controllable and synchronized scrolling behaviour.

Urs

"Robin Tucker" <idontwanttobes pammedanymore@r eallyidont.com> schrieb im
Newsbeitrag news:cufl6j$is1 $1$8300dec7@new s.demon.co.uk.. .[color=blue]
> What you want is a "virtual list view". I don't see ListView as
> particularly viable for this (I have tried it before). In the end I wrote
> my own control which does the same and allows me to owner draw each row
> (including images in cells).
>
>
> "Urs Vogel" <uvogel@msn.com > wrote in message
> news:umwGzz2DFH A.208@TK2MSFTNG P12.phx.gbl...[color=green]
>> Hi
>>
>> I'm looking for a way to trap the ListView's scroll events, in order to
>> control page-wise loading of not bindable data. Any hints of how to
>> achieve this?
>>
>> Thanks, Urs
>>[/color]
>
>[/color]

[Ken Tucker [MVP]]

Re: ListView Scroll Event

Hi,

Use the native window class to listen for the scroll messages on
the listbox. Will work with any control.

' NativeWindow class to listen to operating system messages.

Private Class MyListener

Inherits NativeWindow

Public Event MyScroll(ByVal sender As Object, ByVal e As EventArgs)

Const WM_MOUSEACTIVAT E = &H21

Const WM_MOUSEMOVE = &H200



Private ctrl As Control

Public Sub New(ByVal ctrl As Control)

AssignHandle(ct rl.Handle)

End Sub

Protected Overrides Sub WndProc(ByRef m As Message)

' Listen for operating system messages

Const WM_HSCROLL = &H114

Const WM_VSCROLL = &H115





If m.Msg = WM_Hscroll Or m.Msg = wm_vscroll Then

RaiseEvent MyScroll(ctrl, New EventArgs)

End If

MyBase.WndProc( m)

End Sub

Protected Overrides Sub Finalize()

ReleaseHandle()

MyBase.Finalize ()

End Sub

End Class

Dim WithEvents sl As MyListener

Private Sub Form1_Load(ByVa l sender As System.Object, ByVal e As
System.EventArg s) Handles MyBase.Load

sl = New MyListener(List Box1)

end sub



Private Sub sl_MyScroll(ByV al sender As Object, ByVal e As System.EventArg s)
Handles sl.MyScroll

Me.Text = "Scroll"

End Sub






Ken

-------------------------------
"Urs Vogel" <uvogel@msn.com > wrote in message
news:umwGzz2DFH A.208@TK2MSFTNG P12.phx.gbl...
Hi

I'm looking for a way to trap the ListView's scroll events, in order to
control page-wise loading of not bindable data. Any hints of how to achieve
this?

Thanks, Urs