firemonkey (FMX) 中的 IndexFieldNames 问题

Question

The problem occurs only in firemonkey. With VCL it works perfectly.

I have a dataset (of any type) connected to a grid (of any type) when clicking on the title of the column this must be ordered by the corresponding field.

For VCL

procedure TForm2.DBGrid1TitleClick(Column: TColumn);
begin
  qrySec.IndexFieldNames := Column.FieldName;
end;

For FMX

procedure TManFarmaQry.StringGrid1HeaderClick(Column: TColumn);
begin
     
case Column.Index of
          0:
            if mtblMedica.IndexFieldNames = 'Field1' then
              mtblMedica.IndexFieldNames := 'Field1' + ':D'
            else
              mtblMedica.IndexFieldNames := 'Field1';
    
          1:
            if mtblMedica.IndexFieldNames = 'Field2' then
              mtblMedica.IndexFieldNames := 'Field2' + ':D'
            else
              mtblMedica.IndexFieldNames := 'Field2';
          2:
            if mtblMedica.IndexFieldNames = 'Field3' then
              mtblMedica.IndexFieldNames := 'Field3' + ':D'
            else
              mtblMedica.IndexFieldNames := 'Field3';
        end;
end;

In the case of FMX, a rearrangement of the registers is observed but it does not correspond to anything. Leaving everything untidy.

I think that since Firedac is used in both cases, the problem is not there. Then there is a synchronization problem in the bind.

Delphi 10.3.3

Answer 1

Hoping that the solution I found will serve someone else, here I leave it.

procedure TManFarmaQry.StringGrid1HeaderClick(Column: TColumn);
begin
  // Putting things practical    
      if mtblMedica.IndexFieldNames = LinkGridToDataSourceBindSourceDB1.Columns[Column.Index].MemberName then
        mtblMedica.IndexFieldNames := LinkGridToDataSourceBindSourceDB1.Columns[Column.Index].MemberName + ':D'
      else
        mtblMedica.IndexFieldNames := LinkGridToDataSourceBindSourceDB1.Columns[Column.Index].MemberName;

    
    // Here is the solution. Refresh datasource
        LinkGridToDataSourceBindSourceDB1.Active := False;
        LinkGridToDataSourceBindSourceDB1.Active := True;

end;