[mcone]

The v 7.22 PaintListBox returns a List index out of bounds (0) error at this line when displaying a TsListBox:

Code:

DrawItemStruct.itemData := Longint(Pointer(Items.Objects));

The pertinent error information from MadExcept is:

Code:

exception number : 1
exception class : EStringListError
exception message : List index out of bounds (0).

main thread ($1f10):
0087ea6a +016e vTube.exe sListBox 146 +0 PaintListBox
0087ebe9 +0075 vTube.exe sListBox 146 +0 TsCustomListBox.WMPaint
00550364 +02d4 vTube.exe Controls TControl.WndProc
00554c2c +0568 vTube.exe Controls TWinControl.WndProc
004e6080 +00f0 vTube.exe StdCtrls TCustomListBox.WndProc
0087ee19 +01e9 vTube.exe sListBox 146 +0 TsCustomListBox.WndProc
0067ca10 +0030 vTube.exe acSBUtils TacMainWnd.CallPrevWndProc
00674f7c +06a4 vTube.exe acSBUtils TacScrollWnd.acWndProc
0067a200 +00e4 vTube.exe acSBUtils TacBaseWnd.acWndProc
0067569e +06e2 vTube.exe acSBUtils TacEditWnd.acWndProc
005542cc +002c vTube.exe Controls TWinControl.MainWndProc
004a8698 +0014 vTube.exe Classes StdWndProc
77cf00e3 +002b ntdll.dll KiUserCallbackDispatcher
767ecd7c +0047 USER32.dll SendMessageW
0067532b +036f vTube.exe acSBUtils TacEditWnd.acWndProc
005542cc +002c vTube.exe Controls TWinControl.MainWndProc
004a8698 +0014 vTube.exe Classes StdWndProc
77cf00e3 +002b ntdll.dll KiUserCallbackDispatcher
767ecd7c +0047 USER32.dll SendMessageW
0063d571 +0225 vTube.exe sVclUtils SkinPaintTo
0063d659 +030d vTube.exe sVclUtils SkinPaintTo
00640154 +093c vTube.exe sVclUtils AnimShowControl
005e849d +008d vTube.exe sPageControl TsPageControl.CNNotify
00550364 +02d4 vTube.exe Controls TControl.WndProc
00554c2c +0568 vTube.exe Controls TWinControl.WndProc
005ec169 +1209 vTube.exe sPageControl TsPageControl.WndProc
0054ff88 +0024 vTube.exe Controls TControl.Perform
00554d7f +0023 vTube.exe Controls DoControlMsg
00555809 +000d vTube.exe Controls TWinControl.WMNotify
00550364 +02d4 vTube.exe Controls TControl.WndProc
00554c2c +0568 vTube.exe Controls TWinControl.WndProc
0057734c +0594 vTube.exe Forms TCustomForm.WndProc
005542cc +002c vTube.exe Controls TWinControl.MainWndProc
004a8698 +0014 vTube.exe Classes StdWndProc
77cf00e3 +002b ntdll.dll KiUserCallbackDispatcher
767ecd7c +0047 USER32.dll SendMessageW
739e8764 +0048 comctl32.dll #342
767f0ad1 +0016 USER32.dll CallWindowProcW
00554d2c +00d8 vTube.exe Controls TWinControl.DefaultHandler
005509e1 +0015 vTube.exe Controls TControl.WMLButtonDown
0050bad1 +000d vTube.exe ComCtrls TPageControl.WMLButtonDown
00550364 +02d4 vTube.exe Controls TControl.WndProc
00554c2c +0568 vTube.exe Controls TWinControl.WndProc
005ec169 +1209 vTube.exe sPageControl TsPageControl.WndProc
004a8698 +0014 vTube.exe Classes StdWndProc
005542cc +002c vTube.exe Controls TWinControl.MainWndProc
004a8698 +0014 vTube.exe Classes StdWndProc
767e7df5 +000a USER32.dll DispatchMessageW
0058044d +011d vTube.exe Forms TApplication.ProcessMessage
00580492 +000a vTube.exe Forms TApplication.HandleMessage
005807bd +00c9 vTube.exe Forms TApplication.Run
0097481e +0366 vTube.exe vTube 235 +47 initialization
77323675 +0010 kernel32.dll BaseThreadInitThunk

The temporary solution to get the code working is to rem out the DrawItemStruct line.

Code:

//DrawItemStruct.itemData := Longint(Pointer(Items.Objects));

I cannot see any observable problems at runtime after I rem out the code. But I assume that you need it there and provide this post so that you can take a look at fixing the problem.

Mike

[mcone]

This problem continues in v7.23.

[Support]

Please check the version 7.24 – I have added some checks there, but I can't understand why you have this error.

Maybe you can show me a demo?

Problematic line can't be commented because Data property may be used in many projects…

[mcone]

I found the problem – and it was my fault. Apparently v6 must have been tolerant of this mistake but v7 was not. Thank you for checking anyway – and my apologies.

Example of logic error:

Code:

sListbox_EntityControl.items.clear;

for iX := 1 To iEntSize do
begin
sListbox_EntityControl.items[iX-1] := szText;
end;

Repaired logic:

Code:

sListbox_EntityControl.items.clear;

for iX := 1 To iEntSize do
begin
sListbox_EntityControl.items.add(szText);
end;

[Author]

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