DrBonzo
28th October 2011 18:12 UTC

having trouble with NSD_OnNotify with ListBox
I'm trying to respond to clicks on a listbox. Here's the setup:

nsDialogs::Create /NOUNLOAD 1018
Pop $ListBoxPage
${NSD_CreateListBox} 0 20 100% 80% "Backup folders"
Pop $ListBox
Call PopulateListBox
${NSD_OnNotify} $ListBox ListClicked
nsDialogs::Show

The list box is getting populated, but ListClicked is never getting called.

What am I missing?

Anders
29th October 2011 17:55 UTC

Not every notification works for every control. OnNotify hooks WM_NOTIFY and a listbox does not use that message IIRC

DrBonzo
31st October 2011 14:49 UTC

Thanks, Anders, for your reply.

Yes, indeed, listboxes neither generate nor receive WM_NOTIFY messages for selection changes. I had been encouraged by another thread (http://forums.winamp.com/showthread....ght=lbs_notify) mentioning LBS_NOTIFY, but that poster was looking for OnChange notifications.

The MSDN dox say that the list box's *parent* ($ListBoxPage in my example) receives selection change notifications and I've verified with Spy++ that, in fact, this notification is in the form of a WM_COMMAND message with a wNotifyCode (HIWORD of wParam) of LBN_SELCHANGE.

So it looks like I need to subclass $ListBoxPage. I've found WndSubclass - http://nsis.sourceforge.net/WndSubclass_plug-in (yours, Anders?), which looks like it might do the trick. If so, I'll post the results. If not, I'll probably ask for more help...

DrBonzo
31st October 2011 17:18 UTC

Thanks to WndSubclass, here's a working example :

Page custom ListBoxDialogPage
OutFile ListBoxTest.exe

Section "Empty section"
SectionEnd

!include LogicLib.nsh
!include NsDialogs.nsh
!include WinMessages.nsh
!include WndSubclass.nsh

var ListBox
var ListBoxPage

!define __NSD_ListBoxMulti_CLASS LISTBOX
!define __NSD_ListBoxMulti_STYLE ${DEFAULT_STYLES}|${WS_TABSTOP}|${WS_VSCROLL}|${LBS_EXTENDEDSEL}|${LBS_HASSTRINGS}|${LBS_NOTIFY}
!define __NSD_ListBoxMulti_EXSTYLE ${WS_EX_WINDOWEDGE}|${WS_EX_CLIENTEDGE}

!insertmacro __NSD_DefineControl ListBoxMulti

Function PopulateListBox
    SendMessage $ListBox ${LB_ADDSTRING} 0 "STR:Abel"
    SendMessage $ListBox ${LB_ADDSTRING} 0 "STR:Baker"
    SendMessage $ListBox ${LB_ADDSTRING} 0 "STR:Charlie"
FunctionEnd

Function ListClicked
        SendMessage $ListBox ${LB_GETCURSEL} 0 0 $0
        MessageBox MB_OK "Cursel: $0"
FunctionEnd

Var CommandCaptureVar

!define LBN_SELCHANGE 1

Function CommandCapture
        ${If} $2 = ${WM_COMMAND}
            Var /Global HiWord
            IntOp $HiWord $3 >> 16
            IntOp $HiWord $HiWord & 0xff
            ${If} $HiWord = ${LBN_SELCHANGE}
                        Call ListClicked
            ${EndIf}
        ${EndIf}
FunctionEnd

Function ListBoxDialogPage
        nsDialogs::Create /NOUNLOAD 1018
        Pop $ListBoxPage
        ${NSD_CreateListBoxMulti} 0 20 100% 80% ""
        Pop $ListBox
        Call PopulateListBox
        ${WndSubclass_Subclass} $ListBoxPage CommandCapture $CommandCaptureVar $CommandCaptureVar
        nsDialogs::Show
FunctionEnd