为何我在编辑DBGRIDEH的某一单元格时，颜色还会变红色。

Question

有列字段，名为累计额。我想当些字段中负数的单元格在显示时为红色，正数的就为黑色，我在此事件里写：
procedure TForm1.DBGridEh1DrawColumnCell(Sender: TObject;
  const Rect: TRect; DataCol: Integer; Column: TColumnEh;
  State: TGridDrawState);
begin
if (adoquery2.FieldValues['addupSum']<0) and (adoquery2.State<>dsEdit) then
  begin
  dbgridEh1.Columns[3].font.color:=clred;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end
else
  begin
  dbgridEh1.Canvas.Font.Color:=clblack;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end;end;但是问题来了，当有记录是负数的时，我修改任意一条记录的“累计额”这一单元格的值都会是输入红色的字，但按回车后又恢复黑字。谁能告诉怎么不让它变红字呢？

Answer 1

dbgridEh1.Canvas.Font.Color:=clblack;你这句是不是加上：
    if (gdSelected in State) then      dbgridEh1.Canvas.Font.Color := clblack;
    dbgridEh1.DefaultDrawColumnCell(Rect,DataCol,Column,State);

Answer 2

你这里的代码写得也不对吧：
  begin
  dbgridEh1.Columns[3].font.color:=clred;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end
else
  begin
  dbgridEh1.Canvas.Font.Color:=clblack;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end;

Answer 3

procedure TForm1.DBGridEh1DrawColumnCell(Sender: TObject;
  const Rect: TRect; DataCol: Integer; Column: TColumnEh;
  State: TGridDrawState);
begin
  if (adoquery2.FieldValues['addupSum']<0) and (adoquery2.State<>dsEdit) then
    dbgridEh1.Columns[3].font.color:=clred;
  else
　  dbgridEh1.Canvas.Font.Color:=clblack;  if (gdSelected in State) then
    Column.Font.Color := clblack;
    dbgridEh1.DefaultDrawColumnCell(Rect,DataCol,Column,State);
end;这样看看行不行吧！

Answer 4

if (adoquery2.FieldValues['addupSum']<0) and (adoquery2.State<>dsEdit) then
  begin
  dbgridEh1.Columns[3].font.color:=clred;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end
else
  begin
  dbgridEh1.Canvas.Font.Color:=clblack;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
end;if DBGridEh1.DataSource.DataSet.State in [dsEdit, dsInsert] then
begin
  dbgridEh1.Canvas.Font.Color:=clGrean;
  dbgridEh1.InplaceEditor.Brush.Color:=clGrean;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
end;//这样行吗？

Answer 5

procedure TForm1.DBGridEh1DrawColumnCell(Sender: TObject;
  const Rect: TRect; DataCol: Integer; Column: TColumnEh;
  State: TGridDrawState);
begin
if (adoquery2.FieldValues['addupSum']<0) and (adoquery2.State=dsBrowse) then
  begin
  dbgridEh1.Columns[3].font.color:=clred;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end
else
  begin
  dbgridEh1.Canvas.Font.Color:=clblack;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end;end;

Answer 6

我想这不是解决的方法，事件在修改时好像发生在DBGridEh1DrawColumnCell之前，唯一的办法是把我的下面这个事件换另一种方法。
if (adoquery2.FieldValues['addupSum']<0) and (adoquery2.State<>dsEdit) then
  begin
  dbgridEh1.Columns[3].font.color:=clred;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
  end
else
  begin
  dbgridEh1.Canvas.Font.Color:=clblack;
  dbgridEh1.DefaultDrawColumnCell(rect,DataCol,Column,State);
end;