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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>A good spot, but this code doesn&#8217;t solve it either.&nbsp; It provides a universal way of handling scrollbar or mousewheel scroll notifications, although a bit of extra &nbsp;work is then required to discriminate between H vs V scrolling, but when I added this to my listview class it didn&#8217;t get called as the result of keyboard scrolling either.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Couple of supplementary questions: <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p>&nbsp;</o:p></span></p><p class=MsoListParagraph style='margin-left:22.5pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Where do you get TWMNotifyLV from?&nbsp; Why not just use TWMNotify ?<o:p></o:p></span></p><p class=MsoListParagraph style='margin-left:22.5pt;text-indent:-18.0pt;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Why not use the &nbsp;LVN_BEGINSCROLL/LVN_ENDSCROLL constants, rather than literals + comments ?<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p>&nbsp;</o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p>&nbsp;</o:p></span></p><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> delphi-bounces@delphi.org.nz [mailto:delphi-bounces@delphi.org.nz] <b>On Behalf Of </b>Jeremy North<br><b>Sent:</b> Friday, 25 February 2011 16:21<br><b>To:</b> NZ Borland Developers Group - Delphi List<br><b>Subject:</b> Re: [DUG] Listview problem<o:p></o:p></span></p></div><p class=MsoNormal><o:p>&nbsp;</o:p></p><div><p class=MsoNormal>Don't forget &quot;scrolling&quot; also occurs when you use the arrow keys.<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>My contribution (just made up then)...<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>unit ScrollingListView;<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>interface<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>uses<br>&nbsp; Windows, Messages, ComCtrls, CommCtrl, Controls;<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>type<br>&nbsp; TJSListView = class(TListView)<br>&nbsp; private<br>&nbsp;&nbsp;&nbsp; type<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; TJSScrollEvent = procedure (Sender: TObject; const BeginScroll: Boolean) of object;<br>&nbsp;&nbsp;&nbsp; var<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; FOnEndScroll: TJSScrollEvent;<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; FOnBeginScroll: TJSScrollEvent;<br>&nbsp; protected<br>&nbsp;&nbsp;&nbsp; procedure DoScroll(const AStart: Boolean); virtual;<br>&nbsp;&nbsp;&nbsp; procedure CNNotify(var Message: TWMNotifyLV); message CN_NOTIFY;<br>&nbsp; public<br>&nbsp;&nbsp;&nbsp; property OnBeginScroll: TJSScrollEvent read FOnBeginScroll write FOnBeginScroll;<br>&nbsp;&nbsp;&nbsp; property OnEndScroll: TJSScrollEvent read FOnEndScroll write FOnEndScroll;<br>&nbsp; end;<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>implementation<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>{ TJSListView }<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>procedure TJSListView.CNNotify(var Message: TWMNotifyLV);<br>begin<br>&nbsp; if Message.NMHdr.code = -180 then // LVM_BEGINSCROLL<br>&nbsp; begin<br>&nbsp;&nbsp;&nbsp; DoScroll(True);<br>&nbsp; end;<br>&nbsp; if Message.NMHdr.code = -181 then // LVM_ENDSCROLL<br>&nbsp; begin<br>&nbsp;&nbsp;&nbsp; DoScroll(False);<br>&nbsp; end;<br>&nbsp; inherited;<br>end;<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>procedure TJSListView.DoScroll(const AStart: Boolean);<br>var<br>&nbsp; LEvent: TJSScrollEvent;<br>begin<br>&nbsp; if AStart then<br>&nbsp;&nbsp;&nbsp; LEvent := OnBeginScroll<br>&nbsp; else<br>&nbsp;&nbsp;&nbsp; LEvent := OnEndScroll;<br>&nbsp; if Assigned(LEvent) then<br>&nbsp;&nbsp;&nbsp; LEvent(Self, AStart);<br>end;<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>end.<o:p></o:p></p></div><div><p class=MsoNormal>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal><br><br>&nbsp;<o:p></o:p></p></div><div><p class=MsoNormal>On Fri, Feb 25, 2011 at 2:01 PM, David O'Brien &lt;<a href="mailto:Dave@iccs.co.nz">Dave@iccs.co.nz</a>&gt; wrote:<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>Sorted it thanks, had mixed versions of code in the component. The events do fire&#8230;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:10.0pt'>From:</span></b><span lang=EN-US style='font-size:10.0pt'> <a href="mailto:delphi-bounces@delphi.org.nz" target="_blank">delphi-bounces@delphi.org.nz</a> [mailto:<a href="mailto:delphi-bounces@delphi.org.nz" target="_blank">delphi-bounces@delphi.org.nz</a>] <b>On Behalf Of </b>Jolyon Smith<br><b>Sent:</b> Friday, 25 February 2011 3:43 p.m. <o:p></o:p></span></p><div><p class=MsoNormal><span lang=EN-US style='font-size:10.0pt'><br><b>To:</b> 'NZ Borland Developers Group - Delphi List'<o:p></o:p></span></p></div><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt'>Subject:</span></b><span lang=EN-US style='font-size:10.0pt'> Re: [DUG] Listview problem</span><span lang=EN-US> </span><o:p></o:p></p></div></div><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>&nbsp;<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>A WM_VSCROLL message handler works perfectly for me.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>However, this will only be sent for scrollbar directed scrolling.&nbsp; To also handle mousewheel scrolling you will have to implement a WM_MOUSEWHEEL message handler &nbsp;(and WM_HMOUSEWHEEL if appropriate to your needs).&nbsp; Could it be mouse scrolling that you are missing ?</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>I would also note that you will almost certainly want to distinguish between H and V scrolling, rather than have a &#8220;universal&#8221; &#8220;some sort of scrolling has occurred&#8221; notification.&nbsp; You may also wish to be able to respond both before and after scrolling has occurred.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>In my list view class I have:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; TScrollNotification = (</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snBeforeHScroll,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snBeforeHWheel,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snBeforeVScroll,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snBeforeWheel,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;snHScroll,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snHWheel,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snVScroll,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; snWheel</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; );</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; procedure TXListview.WMVScroll(var aMessage: TWMVScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; DoScroll(snBeforeVScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; inherited;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; DoScroll(snVScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; procedure TXListview.WMHScroll(var aMessage: TWMHScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; DoScroll(snBeforeHScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; inherited;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; DoScroll(snHScroll);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>and similar for mousewheel messages of course, where DoScroll:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; procedure TXListview.DoScroll(const aNotification: TScrollNotification);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; if (aNotification in [snBeforeHScroll, snBeforeVScroll, snBeforeHWheel, snBeforeWheel]) then</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; CancelEdit;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; if Assigned(fOnScroll) then</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; fOnScroll(self, aNotification);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>i.e. my listview also provides a facility for sub-item editing and when scrolling occurs, the first thing I do before doing the actual scrolling is dismiss any sub-item editor that may be active, before then firing the OnScroll event to allow my application code to respond as it may require.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>hth</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-US style='font-size:10.0pt'>From:</span></b><span lang=EN-US style='font-size:10.0pt'> <a href="mailto:delphi-bounces@delphi.org.nz" target="_blank">delphi-bounces@delphi.org.nz</a> [mailto:<a href="mailto:delphi-bounces@delphi.org.nz" target="_blank">delphi-bounces@delphi.org.nz</a>] <b>On Behalf Of </b>David O'Brien<br><b>Sent:</b> Friday, 25 February 2011 15:09<br><b>To:</b> NZ Borland Developers Group - Delphi List<br><b>Subject:</b> [DUG] Listview problem</span><o:p></o:p></p></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>&nbsp;<o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>I am working on an application (D2009) where I need to know when a TListView is Scrolled.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>I have used Application.OnMessage to look for WM_VScroll messages, but they do not happen, also have tried creating the below which I thought should work:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; TLVScrollEvent = procedure(Sender: TObject) of object;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; TICListView = class(TListView)</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; private</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; FOnScroll: TLVScrollEvent;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; protected</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; Procedure WMVScroll( Var Msg: TMessage ); message WM_VSCROLL;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; Procedure WMHScroll( Var Msg: TMessage ); message WM_HSCROLL;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;&nbsp;&nbsp; property OnScroll: TLVScrollEvent read FOnScroll write FOnscroll ;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>procedure Register ;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>implementation</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>procedure Register;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; RegisterComponents('Dave', [TICListView]);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>procedure TICListView.WMHScroll(var Msg: TMessage);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; OnScroll ;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; inherited;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>procedure TICListView.WMVScroll(var Msg: TMessage);</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>begin</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; OnScroll ;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp; inherited;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>end;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;color:#1F497D'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>which also doesn&#8217;t fire. I have written a list of all messages fired when the scrollbar is moved, but there doesn&#8217;t seem to be anything useful&#8230;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>Anyone have a solution?</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>&nbsp;</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>Regards,</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt'>Dave.</span><o:p></o:p></p></div></div></div></div><p class=MsoNormal><br>_______________________________________________<br>NZ Borland Developers Group - Delphi mailing list<br>Post: <a href="mailto:delphi@delphi.org.nz">delphi@delphi.org.nz</a><br>Admin: <a href="http://delphi.org.nz/mailman/listinfo/delphi" target="_blank">http://delphi.org.nz/mailman/listinfo/delphi</a><br>Unsubscribe: send an email to <a href="mailto:delphi-request@delphi.org.nz">delphi-request@delphi.org.nz</a> with Subject: unsubscribe<o:p></o:p></p></div><p class=MsoNormal><o:p>&nbsp;</o:p></p></div></body></html>