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Posted: **Sat 26 Jan 2008 16:53**

Hi all,
Can anyone help me out with the following problem.
I create the following Form elements (TDBGridEh, TMyDataSource, TMyQuery) in the RunTime mode.
Then, using Query, I fill in created tables. One column in each table gets populated using PickList. Here is the actual problem. How would I go about processing the Event, when the user picks any value from the DropDownBox for the table created in the RunTime mode?

Code: Select all

procedure TFRM_Work_Shedule.FormCreate(Sender: TObject);
var TableClass, SourceClass, QueryClass: TControlClass;
    Work_Shedule_Table, Work_Shedule_DataSource, Work_Shedule_Query, Doctors_Query: TControl;
    i, j, table_width, table_coordinate, cabs_number: Integer;
    selecting_SQL, create_table_SQL: String;
begin
...
        i:=0;
        table_coordinate:=0;
        TableClass:=TControlClass(TDBGridEh);
        SourceClass:=TControlClass(TMyDataSource);
        QueryClass:=TControlClass(TMyQuery);
        while i<cabs_number do
        begin
        for j:=1 to 2 do
        begin
           Work_Shedule_Table:=TableClass.Create(WorkShedule_Doctors_SBox);
           Work_Shedule_Table.Parent:=WorkShedule_Doctors_SBox;
           Work_Shedule_DataSource:=SourceClass.Create(WorkShedule_Doctors_SBox);
           Work_Shedule_Query:=QueryClass.Create(WorkShedule_Doctors_SBox);
           Doctors_Query:=QueryClass.Create(WorkShedule_Doctors_SBox);

           TMyDataSource(Work_Shedule_DataSource).DataSet:=TMyQuery(Work_Shedule_Query);
           TDBGridEh(Work_Shedule_Table).DataSource:=TMyDataSource(Work_Shedule_DataSource);

           TDBGridEh(Work_Shedule_Table).TitleLines:=2;
           TDBGridEh(Work_Shedule_Table).Flat:=true;
           TDBGridEh(Work_Shedule_Table).Height:=WorkShedule_Doctors_SBox.Height;
           TDBGridEh(Work_Shedule_Table).Width:=150;
           table_width:=TDBGridEh(Work_Shedule_Table).Width;
           TDBGridEh(Work_Shedule_Table).Left:=table_coordinate;
           TDBGridEh(Work_Shedule_Table).AutoFitColWidths:=true;


           TMyQuery(Doctors_Query).Connection:=Data_Module.RBase_Connection;
           TMyQuery(Doctors_Query).SQL.Clear;
           TMyQuery(Doctors_Query).SQL.Add('SELECT * FROM doctorsref');
           TMyQuery(Doctors_Query).Execute;
           TDBGridEh(Work_Shedule_Table).Columns.Add.FieldName:='work_time';
           TDBGridEh(Work_Shedule_Table).Columns.Add.FieldName:='doctor_name';
           while not TMyQuery(Doctors_Query).Eof do
           begin
              TDBGridEh(Work_Shedule_Table).Columns.Items[1].PickList.Add(TMyQuery(Doctors_Query).FieldByName('doc_lname').AsString);
              TMyQuery(Doctors_Query).Next;
           end;
... ^^^^^^^^^^^^^^^^^^^^^^^^^^^'doctor_name' column Event
end;

Thanks in advance for any help

Posted: **Tue 29 Jan 2008 15:07**

In order to process such event you can try to handle the TField.OnChange event. For that perform the next steps.
Create an event handler, for example:

Code: Select all

procedure TFRM_Work_Shedule.OnFieldChange(Sender: TField);
begin
  ShowMessage(Sender.AsString);
end;

Set this event handler for required field:

Code: Select all

  TMyQuery(Work_Shedule_Query).FieldByName('doctor_name').OnChange := OnFieldChange;

Posted: **Tue 29 Jan 2008 20:35**

Yeah, tried that. Also tried using event UpdateData and the final result is the same. The problem is that when I choose any value from the list (DropDownBox), the event gets processed only after the current cell’s selection is lost. But what I need is the event triggered at the same time the value from the list gets selected.

Posted: **Wed 30 Jan 2008 13:31**

This question is out of the MyDAC support scopes. Please ask it in the corresponding forum of the EhLib site.

Devart Forums

Help with processing Event for the component created in the RunTime mode.

Help with processing Event for the component created in the RunTime mode.