I am new user of Delphi and now want to write some data into the DrawGrid. How can i do that?
You only use a TDrawGrid to display information in a tabular form, if the information
can not be displayed as textual data (such as images or a combination of images and
text). With a TDrawGrid, your code has to draw everything on the grid's "Canvas",
its drawing surface.
A TDrawGrid doesn't have a property "Cells", like its brother TStringGrid. Your code
has to calculate where to display the data and next it must draw a representation of
the data on the "Canvas" of the grid. For pure text, this can be done with TextOut.
The simplest example would be:
DrawGrid1.Canvas.TextOut(X, Y, 'ABC');
This will display the string 'ABC' in the font of the TDrawGrid, starting from the
point with coordinates X and Y (horizontal and vertical position in pixels, relative
left and the top of the grid). In most cases, you draw in the grid's OnDrawCell event;
you receive a "rectangle" from Delphi, in which you can draw your data. An example:
procedure TForm1.DrawGrid1DrawCell(Sender: TObject; ACol,
ARow: Integer; Rect: TRect; State: TGridDrawState);
Sx, Sy: string;
Sx := IntToStr(ARow);
Sy := IntToStr(ACol);
with DrawGrid1 do begin
Canvas.TextOut(Rect.Left + 2, Rect.Top + 2,
'Row ' + Sx + ', Column ' + Sy);
if gdFocused in State then
For drawing images in a TDrawGrid, it's a bit more complicated, but I'm not going to write
an entire tutorial here ;-)
If you only want to display *textual* data (of the type "string"), or if you can convert
the data to a string (using IntToStr for integers, and so on...), it's a lot easier
if you use a TStringGrid:
procedure TForm1.Button1Click(Sender: TObject);
X, Y: integer;
Sx, Sy: string;
with StringGrid1 do
for X := 0 to RowCount - 1 do
for Y := 0 to ColCount - 1 do begin
Sx := IntToStr(X);
Sy := IntToStr(Y);
Cells[Y, X] := 'Row ' + Sx + ', Column ' + Sy;
With a TStringGrid, you just fill the cells and then it's done. Your code doesn't have
to draw the visible cells, nor does it have to show the grid's focus rectangle, all that
is done automatically.
For database tables, you use a TDBGrid.