[Solved] TDBLookupComboBox selected value

[madref]

I have a DBLookupComboBox which i uses to select things.
When i use the OnChange-Event handler. I always get the previous selection.


How can i get the current selection?

Code: Pascal  [Select][+][-]

1.  DBLCB.KeyValue

Does not work.


This is the complete code i use:

Code: Pascal  [Select][+][-]

1. procedure TForm_WedstrijdInformatie.CB_TeamAChange(Sender: TObject);
2. var pi,ta: integer;
3. begin
4.   pi := MLookup('Team_Plaats_ID','tbl_Teams','Team_ID='+IntToStr(CB_TeamA.KeyValue));
5.   TQ_Wedstrijd.FieldByName('Wed_Plaats').AsInteger := pi;
6. end;     // CB_TeamAChange

P.S. MLookUp is my variant of the Delphi DLookUp

[wp]

There were a lot of changes with the db comboboxes recently. Please try Laz 1.8.2 (or trunk).

[madref]

i am using 1.8.2

[wp]

I thought I saw 1.8.0 in your signature...

Anyway. Are you using the DBLookupCombobox correctly? It has two Datasources, the "normal" DataSource attached to the dataset that you want to change, and the "ListSource" from which you get the lookup values, as well as fields DataField (belonging to DataSource), KeyField and ListField (belonging to ListSource). ListField will be displayed, and the DataField and Keyfield values must match.

From your code snippets I guess must make these assignments within TDBLookupCombobox
- DataSource --> TQ_Wedstrijd
-  DataField --> Wed_Plaats
- ListSource --> tbl_Teams
- KeyField --> Team_Plaats_ID
- ListField --> (I don't know your fields. It is the field in tbl_Teams which you want to display in the combobox.

[madref]

DataSource = DS_Wedstrijd
DataField = Wed_TeamA
ListSource = DS_Teams
KeyField = Team_ID
ListField = Team_Naam


What i do is depending on the team i select. I then determine the place of the ice rink where they play their home games (with the function MLookUp).
In previous version of Lazarus this always worked as i have done in the example i posted.


What has changed then in Lazarus 1.8.2.

[madref]

All set with this code

Code: Pascal  [Select][+][-]

1.   CB_TeamA.ListSource := DS_Teams;
2.   CB_TeamA.ListField := 'Team_Naam';
3.   CB_TeamA.KeyField := 'Team_ID';

[madref]

What has changed in de DBLookupCombobox in 1.8.2. to 1.8.0?

[madref]

I switched back to 1.8.0 and everything works fine again
I think theres a big in it.

[wp]

You should try to separate the issue into a minimal project which you upload here.

[madref]

Here is an older version but with the same problem in 1.8.0 (working correctly) vs 1.8.2 (working weird).

[wp]

I'm on Windows, had to remove one of the units, and now the program does not even start. Giving up here. I don't have the time to debug a foreign program, sorry.

[madref]

I really don't know why it doesn't work.
But i have removed some redundant code and units.


Hope it works now.

[wp]

No chance, still the same: Crashing the debugger, and when run without the debugger I get "A reference evaluation was sent back by server" (whatever that means...). Further reduce the project. Remove unnecessary sqlqueries, try to avoid the two-stage layout of main form -> second form, put everything needed into the same form. Yes, that takes some time, but I will spend my time on that, too.

[rvk]

I got it working here om Windows after fiddling with some options.

So what is the problem? If I put a Showmessage() in CB_DivisieChange() it gives me the value I choose.

Code: Pascal  [Select][+][-]

1. procedure TForm_Wedstrijden_Overzicht.CB_DivisieChange(Sender: TObject);
2. begin
3.   Showmessage(CB_Divisie.KeyValue); // <---- works fine
4.   WedstrijdenSelectie;
5. end;     // CB_DivisieChange

[madref]

When i run this code in a Mac with Lazarus 1.8.2 i get the old value of the combobox when i change it.
In 1.8.0 i get the chosen value.


That is the problem i have. I posted this so anyone else can try and get the same result as i have. Then we know that it is a bug