学习unigui【18】unidbgrid的GridsGroupingSorting

折腾二天，你不按照demo里的代码来，就是没有效果。功力不够导致的。学习学习再学习！努力努力再努力！

procedure TUniGridsGroupingSorting.UniDBGrid1MultiColumnSort(
  Columns: TUniDBGridColumnArr; Directions: TUniSortDirections);
var
  OrderStr : string;
  I : Integer;
begin
  UniMainModule.ADOQuery5.Close;//必须在UniMainModule
  OrderStr := 'select * from [Customers]' + ' order by ';

  for I := Low(Columns) to High(Columns) do
  begin
    OrderStr := OrderStr + '['+Columns[I].FieldName+ '] '+IfThen(Directions[I], 'ASC', 'DESC')+',';

  end;

  OrderStr := RemoveTrailingChar(OrderStr, ',');

  UniMainModule.ADOQuery5.SQL.Text := OrderStr;
  UniMainModule.ADOQuery5.Open;
end;

其二、点击列排序：

 procedure TUniGridsColumnSort.SortColumn(const FieldName: string; Dir: Boolean);
begin
  if Dir then
    ClientDataSet1.IndexName := FieldName+'_index_asc'
  else
    ClientDataSet1.IndexName := FieldName+'_index_des';
end;

procedure TUniGridsColumnSort.UniDBGrid1ColumnSort(Column: TUniDBGridColumn;
  Direction: Boolean);
begin
  SortColumn(Column.FieldName, Direction);//必须分开写调用
end;

看明白没，必须按这种格式，分开写。否则就是不行。作者没有说明why？再WEB中这处理的理由，你知道WHY？

实际上非常简单：

1、创建内存表TFDMemTable

procedure TUniForm_SelectAPanient.UniFormCreate(Sender: TObject);
var i : Integer;
begin
  UniMainModule.fdqry_QueryPatient.Open('select * from patient_info');   //符合条件的患者资料
  fdmtbl_QueryPatient.CopyDataSet(UniMainModule.fdqry_QueryPatient, [coStructure, coRestart, coAppend]);
  fdmtbl_QueryPatient.Filter := '';
  fdmtbl_QueryPatient.IndexesActive := True;
  UniMainModule.fdqry_QueryPatient.Close;
end;

2、改变index

procedure TUniForm_SelectAPanient.undbgrd1MultiColumnSort(
  Columns: TUniDBGridColumnArr; Directions: TUniSortDirections);
var
  i : integer;
  OrderStr : string;
begin
  OrderStr := '';
  for I := Low(Columns) to High(Columns) do
  begin
    OrderStr := OrderStr + Columns[I].FieldName+ IfThen(Directions[I], ':A', ':D')+';';
  end;
  Delete(OrderStr, Length(OrderStr), 1);
  fdmtbl_QueryPatient.IndexFieldNames := OrderStr;
end;

 good luck！