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Access Violation when form closes

edited September 2002 in General
HELP! - I'm getting an access violation when my report form closes.

The report is trivial, just a few ppDBTexts in the detail band. All is ok
as long as I stick to integer, date or short string fields. As soon as I
try a longer string field, or a ppDBMemo on a memo field, I get the AV.
The AV does not unfortunately occur on any source line in the project.

I've tried this using DBISAM and plain Paradox TTables.

The form is dynamically created and when it closes I call Release. If I
comment the Release out I get the AV when the app exits instead. If I
comment out the ppReport.Print the AV does not occur. It seems any access
to the ppReport component or any of the ppDBText components results in the
AV.

Using 6.03 with D6. MinStack increased to 8000h.

Any ideas?

Dave Riley
Tangent Software Ltd, Reading, UK

Comments

  • edited September 2002
    Here is a dynamic report creation example. It doesn't AV when we run it in
    RB 6.03 or RB 7. Compare this to your project.

    http://www.digital-metaphors.com/tips/DynamicReportCreation.zip

    If you continue to get AV's then give us some code to look at or an example
    we can run and we'll tell you what the problem is.

    Cheers,

    Jim Bennett
    Digital Metaphors

  • edited September 2002
    Dave:

    For the record, I have created many reports dynamically and have not had
    problems. One rule is not to free report components yourself, let the report
    free them. If you continue to have issues after looking at the example Jim
    posted, keep asking questions.

    Ed Dressel
    Team DM
  • edited September 2002
    Thanks Nard & Ed, but...

    It seems the dynamic creation is a red herring. I followed the
    instructions in the ReportBuilder Developer's Guide, "A Quick Test Spin".

    I used the BIIOLIFE table instead. With one ppDBText in the detail band on
    the "Species Name" field it was OK. When I added a ppDBMemo on the "Notes"
    field I got the AV when the app exited.

    I got the same if I used my own table with a ppDBText on a longer String
    field (200 chars).

    I've now discovered that the AV only occurs if the app is run within
    Delphi - so it's obviously being caught by a try..except somewhere and
    ignored. There's no sign of it if the app is run outside Delphi but it's
    still a nuisance during development.

    Another report I have contains 4 sub-reports, all on separate pipelines &
    tables (making 5 tables & pipelines in total). When this app exits I get 5
    AVs one after the other.

    Dave Riley
  • edited September 2002
    Also, I just opened the demo program DEMO.DPR in the Demos\Reports folder,
    compiled and ran it - if I double click report 1 (the BIOLIFE one) it
    displays OK, if I then double click report 2 I get an AV. I tried
    switching between a few other reports, most were ok but switching *from*
    report 1 or a few of the other ones causes an AV.

    Dave Riley
    Tangent Software Ltd, Reading, UK
  • edited September 2002
    Hi Dave,

    I can't reproduce what you described, 'Demo.dpr' runs fine for me (D6, RBE7)

    regards,
    Chris Ueberall;
  • edited September 2002
    What is your default printer? Try installing the latest driver available
    from the manufacturer. RB uses the default pritner to measure the placement
    of the controls for the report output. Printer drivers are flaky at best so
    getting the latest one should help. You can also try installing aother
    pritner driver as your default, such as an HP LaserJet 4 or 5 driver as the
    default printer to see if that helps, then we know that it is the driver
    causing the problem.

    You can also try downloading the latest version RB 7 and test with the demo
    version to see if upgrading will solve the problem.


    Cheers,

    Jim Bennett
    Digital Metaphors

  • edited September 2002
    It sounds like you have a bad installation. There is a tech-tip on cleaning
    it up. I would suggest (1) backing up your files if they are in the
    DelphiX\RBuilder directory (don't save files there, they disappear on
    upgrades, I know) and following the instructions for cleaning your
    installation.

    Ed Dressel
  • edited September 2002
    Looks like it's my printer driver (HP DeskJet 990CXi). I changed to a
    different printer (HP LaserJet) and the problem disappeared.

    Thanks Jim,

    Dave.


    On Fri, 20 Sep 2002 09:10:55 -0500, support@digital-metaphors.com (Jim
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