Re-parenting Designer Error when on Data tab

rbuser

v16.03

Hello chaps,

All of our application's forms are embedded into a display panel, and
the Report Designer is no exception, and this is done as per your wiki
example, with the Designer hosted in a borderless form's panel and this
form is itself parented in a main display panel (sounds more complicated
than it really is!)

However, if a user is working on the Designer's Data tab AND there are
LINKED DataViews on there, then if they decide to move away from the
Designer to view a different form in our app (this will re-parent the
Designer's host form to a hidden panel) then the Designer throws an
error. Note, it's fine if the Designer is on any of it's other pages or
if the Data tab contains no DataView LINKS. Can you find a way around
it? The relevant bit of the error stack is below, and you can see it
kicks off with SetParent:


exception class : EAccessViolation
exception message : Access violation at address 00557AFB in module
'HireTrackNX.exe'. Read of address 00000004.

main thread ($1f28):
00557afb +003 HireTrackNX.exe ComCtrls TListItem.GetIndex
00557b26 +012 HireTrackNX.exe ComCtrls TListItem.GetPosition
0055762e +00a HireTrackNX.exe ComCtrls TListItem.GetTop
010a986b +03b HireTrackNX.exe daDataViewToolWin 335 +6
TdaDataViewToolWin.GetFieldPosition
010ab976 +032 HireTrackNX.exe daVisualLink 352 +5 TdaVisualLink.NeedToPaint
010ab8c7 +013 HireTrackNX.exe daVisualLink 296 +2 TdaVisualLink.EventNotify
00a76b9a +056 HireTrackNX.exe ppComm 771 +14
TppCommunicator.SendEventNotify
010a9a57 +027 HireTrackNX.exe daDataViewToolWin 380 +5
TdaDataViewToolWin.WndProc
004fbb40 +02c HireTrackNX.exe Controls TWinControl.MainWndProc
0049ab7c +014 HireTrackNX.exe Classes StdWndProc
77810107 +02b ntdll.dll KiUserCallbackDispatcher
756e9a63 +00e USER32.dll DestroyWindow
004fb4e0 +028 HireTrackNX.exe Controls TWinControl.DestroyWindowHandle
004e05fb +033 HireTrackNX.exe Forms TCustomForm.DestroyWindowHandle
004fb4a8 +050 HireTrackNX.exe Controls TWinControl.DestroyWnd
004fb719 +065 HireTrackNX.exe Controls TWinControl.DestroyHandle
004e05bd +129 HireTrackNX.exe Forms TCustomForm.DestroyHandle
004fb6e9 +035 HireTrackNX.exe Controls TWinControl.DestroyHandle
004e05bd +129 HireTrackNX.exe Forms TCustomForm.DestroyHandle
004fad1c +044 HireTrackNX.exe Controls TWinControl.RemoveControl
004f6a9f +02f HireTrackNX.exe Controls TControl.SetParent
005006ad +04d HireTrackNX.exe Controls TWinControl.SetParent
004ddfac +07c HireTrackNX.exe Forms TCustomForm.SetParent
012e4017 +03b HireTrackNX.exe FormDisplayManager_U 722 +5
TFormDisplayManager.DeactivateForm

nardmoseley

Hi Tom,

I created a patch for RB 16.03 that resolves the issue.

(I was able to modify the rbWiki example and reproduce this issue. )




Best regards,

-
Nard Moseley
Digital Metaphors
www.digital-metaphors.com