What was picked within a columns.picklist? - database

Question

I wasted a bit of time trying to work out something I figured would be simple.
I've got a database with multiple tables (MySQL). One table containing "Components" and another containing "Products". Products are built using Components, for example; Product ABC might be made up of 3 x Screws, 4 x bolts, 1 kilogram of fresh air... etc! Am I making sense so far?
The components are displayed in a DBGrid. If the user makes a mistake and wants to add another "Component" to a "Product" a Picklist appears listing all Components (from a different table) for them to select from.
Now, here's my problem! When something is selected from the column[i].picklist (this is part of a DBGrid) how do I know what was selected. I thought there would be an event fired, but there doesn't seem to be.
I need to know which item was selected so I can retrieve an appropriate description for the next field.
There are 3 fields, they are COMPONENT, DESCRIPTION, QUANTITY. Only COMPONENT and QUANTITY can be edited by the user.
I hope I'm making some sense here.
Here is the code I'm using now (as messy as it is);
procedure TForm1.CompletePolesSourceStateChange(Sender: TObject);
var
loop: Integer;
Tmp: string;
begin
case CompletePolesSource.state of
dsInsert:
begin
CompVals.Clear; // Is a tstringlist created elsewhere
CompVals.Delimiter := '|';
CompVals.QuoteChar := '"';
PoleComponentsGrid.Columns[0].readonly := false; // Is readonly when not in DSInsert
PoleComponentsGrid.Columns[0].PickList.Clear; // Clear other crap
{
Now add Parts to a Name / Value list (CODE / DESCRIPTION) so I can later
get the description without looking it up in the other table.
}
for loop := 1 to componentstable.RecordCount do // Get CODE from other table
begin
componentstable.RecNo := loop;
tmp := componentstable.Fieldbyname('CODE').asstring + '=' + componentstable.Fieldbyname('ITEM').asstring;
CompVals.Add(tmp);
PoleComponentsGrid.Columns.Items[0].PickList.Add(tmp);
end;
PoleComponentsGrid.Columns.Items[0].readonly := true;
end;
end;
end;

Answer 1

This will show the data of the selected rows of the DBGrid
procedure TFrmPrincipal.btnShowSelectedRowsClick(Sender: TObject);
var
i: Integer;
aux: string;
begin
for i := 0 to DBGrid1.SelectedRows.Count - 1 do
begin
ClientDataSet1.GotoBookmark(pointer(DBGrid1.SelectedRows.Items[i]));
aux := aux + IntToStr(ClientDataSet1.RecNo) + ' - ' +
ClientDataSet1.FieldByName('CUSTOMER').AsString + #13;
end;
ShowMessage(‘Selected Rows: ‘ + #13 + aux);
end;