How to change color of dbgrid rows that have the same value on a field in delphi?
for example all rows that have the same teacher
note: those rows are grouped, and come after each other in dbgrid
thanks in advance
You can easily implement this using the DBGrids onDrawColumnCell Event :
procedure TForm1.DBGrid1DrawColumnCell(Sender: TObject; const Rect: TRect;
DataCol: Integer; Column: TColumn; State: TGridDrawState);
begin
if Table1.FieldByName('Teacher').AsString = 'Joe'
then
DBGrid1.Canvas.Brush.Color:=clRed;
DBGrid1.DefaultDrawColumnCell(Rect, DataCol, Column, State);
end;
However, if you do not know the name of the Teachers then you will have to implement some sort of recursive action, this is my implementation :
var TeacherStringList : TStringList;
lastColorUsed : TColor;
AColors : Array of TColor;
function mycolor: TColor;
begin
result := RGB(Random(256), Random(256), Random(256));
end;
procedure TForm3.Button1Click(Sender: TObject);
var CurrS : String;
Index : Integer;
begin
if TeacherStringList.Count <> 0 then TeacherStringList.Clear;
Table1.DisableControls;
try
while not Table1.Eof do
begin
CurrS := Table1.FieldByName('Teacher').AsString;
if (not TeacherStringList.Find(CurrS,Index)) and (not currS.IsEmpty)
then TeacherStringList.Add(CurrS);
Table1.Next;
end;
Table1.First;
SetLength(AColors,TeacherStringList.Count);
for Index := Low(AColors) to High(AColors)
do AColors[Index] := mycolor;
finally
Table1.EnableControls;
end;
end;
procedure TForm3.DBGrid1DrawColumnCell(Sender: TObject; const Rect: TRect;
DataCol: Integer; Column: TColumn; State: TGridDrawState);
var Index : integer;
begin
if (TeacherStringList.Find(Table1.FieldByName('Teacher').AsString,Index))
then
DBGrid1.Canvas.Brush.Color:= AColors[index];
DBGrid1.DefaultDrawColumnCell(Rect, DataCol, Column, State);
end;
procedure TForm3.FormCreate(Sender: TObject);
begin
teacherStringList := TStringList.Create;
teacherStringList.Sorted := True;
end;
procedure TForm3.FormDestroy(Sender: TObject);
begin
teacherStringList.Free;
end;