[Lazarus] Master-detail-subdetail

[michael.vancanneyt at wisa.be]

On Tue, 4 Jan 2011, Koenraad Lelong wrote:

> Hi,
>
> I have a database (firebird) with master-data, detail-data and
> sub-detail-data.
> In lazarus 0.9.28.2, svn 22279, I defined a TIBConnection, a
> TSQLTransaction and three TSQLQuery's. The detail has as its datasource
> a datasource coupled with the master. The subdetail has as its
> datasource a datasource coupled with the detail.
> To show the data I have three TDBGrids, their datasources are those
> three datasources coupled with the three queries.
>
> When I start the application, the master that shows has several details,
> each having several sub-details. When I scroll the details, the
> subdetails follow the detail. That's good. But when I scroll the master,
> only the details follow, the subdetail-grid goes blank.
>
> To try finding what happens I added a button that opens the
> sub-detail-query. If I click on it I get the expected subdetails. When I
> scroll the master again, the subdetail disappears again. Again I can get
> it back by clicking my debug-button.
>
> To debug this further, I added events for beforescroll, afterscroll,
> beforeclose and beforeopen for all three queries which write to a
> logfile. It seems that the beforeclose event is not fired for the
> subdetail-query, although it is closed somehow.
>
> I hope this makes sense to someone. Is there anything I'm missing ? Or
> have I found a bug ?

There is no principle difference between the master/detail and the
detail/subdetail relation, so I'd expect your setup to work.

Can you check whether the AfterScroll events occur for master/detail/subdetail ?

Michael.