Delphi FMX中的多线程

Question

I'm trying to iterate though a TClientDataSet and refresh a TLabel and a TProgressBar in Android, but I get this error. How can I fix it?

This is the execute procedure. is the first time i'm working wuth multithreads in Delphi and i would like to know about that.

I hope you can help me.

procedure TThreadCatalogos.Execute;
    var i : Integer;
        AppPath : string;
    begin
        AppPath := System.IOUtils.TPath.GetPublicPath;
       ProgressBar.Min := 0;

       for i := round(ProgressBar.Min) to round(ProgressBar.Max) do begin
           // check if Self(thread) is terminated, if so exit
           if Terminated then
              Exit;
           Position := i;

           {*******************************************}

            Conexion.Open;
            //CLIENTES
            dsClientes.Open;
            //mtClientes.EmptyDataSet;
            dsClientes.First;
            ProgressBar.Max := dsClientes.RecordCount;
            while not dsClientes.Eof do
            begin
              if not mtClientes.Locate('nombre',dsClientes.FieldByName('nombre').AsString,[]) then
              begin
                Synchronize(procedure()
                begin
                  mtClientes.Insert;
                  mtClientes.Fields[0].Value := dsClientes.FieldByName('cliente_id').Asinteger;
                  mtClientes.Fields[1].Value := dsClientes.FieldByName('nombre').AsString;
                  mtClientes.Fields[2].Value := dsClientes.FieldByName('tipo').AsString;
                  mtClientes.Post;
                  mtClientes.SaveToFile(System.IOUtils.TPath.combine(AppPath,'CLIENTES.bin'),sfBinary);
                  lbl.Text := 'Cliente '+floattostr(ProgressBar.Value)+' de '+floattostr(ProgressBar.Max);
                  ProgressBar.Value := ProgressBar.Value + 1;
                 end);
              dsClientes.Next;
            end;
            //mtClientes.SaveToFile(System.IOUtils.TPath.combine(AppPath,'CLIENTES.xml'),sfXML);
            mtClientes.First;

            end); Exit;

          end;
           {************************************************}

       end;
    end;

Answer 1

To update a progress bar in a main thread from a child thread one approach is to:

1. Use atomically updateable global variable(s), like a 32 bit integer that you update in the child thread.
2. Use a TTimer event on the form that updates the progress bar based off the values in the global variable(s).

This prevents updating the progress bar too often and lets the thread do a very quick updates to progress.