How to put CR/LF into a TStringgrid cell? - delphi

Question

I want to have one fixed row as a header, but the texts are rather long, so I'd like to increase the row height and insert CR/LF into the cell text.
Googling shows this as a solution (and it's the first thing I thought of before googling), but it doesn't seem to work. Any ideas?
Grid.Cells[2,3] := 'This is a sample test' + #13#10 + 'This is the second line';
What happens is that the cell contains This is a sample testThis is the second line
I am using Delphi 7 if it makes any difference.
[Bounty] "My bad. I actually awarded this an answer two years ago without checking and now find that the answer did not work. Apologies to anyone who was misled. This is a frequently asked, often wrongly answered question."
I presume that we are looking to use OnDrawCell, but imagine that we would also have to increase the height of the string grid row which contains the cell.
I will award the answer for either code or a FOSS VCL component.
[Update] must work with Delphi XE2 Starter edition

Answer 1

TStringGrid uses Canvas.TextRect, which uses ExtTextOut, which in turn does not support drawing of multiline text.
You have to draw this yourself in an OnDrawCell event handler with WinAPI's DrawText routine. See for example this answer on how to use DrawText for multiline text, and this recent answer on how to implement custom drawing in OnDrawCell:
type
TForm1 = class(TForm)
StringGrid1: TStringGrid;
procedure FormCreate(Sender: TObject);
procedure StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
Rect: TRect; State: TGridDrawState);
private
procedure FillWithRandomText(AGrid: TStringGrid);
procedure UpdateRowHeights(AGrid: TStringGrid);
end;
procedure TForm1.FillWithRandomText(AGrid: TStringGrid);
const
S = 'This is a sample'#13#10'text that contains'#13#10'multiple lines.';
var
X: Integer;
Y: Integer;
begin
for X := AGrid.FixedCols to AGrid.ColCount - 1 do
for Y := AGrid.FixedRows to AGrid.RowCount - 1 do
AGrid.Cells[X, Y] := Copy(S, 1, 8 + Random(Length(S) - 8));
UpdateRowHeights(AGrid);
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
FillWithRandomText(StringGrid1);
end;
procedure TForm1.StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
Rect: TRect; State: TGridDrawState);
begin
with TStringGrid(Sender) do
if Pos(#13#10, Cells[ACol, ARow]) > 0 then
begin
Canvas.FillRect(Rect);
Inc(Rect.Left, 2);
Inc(Rect.Top, 2);
DrawText(Canvas.Handle, PChar(Cells[ACol, ARow]), -1, Rect,
DT_NOPREFIX or DT_WORDBREAK);
end;
end;
procedure TForm1.UpdateRowHeights(AGrid: TStringGrid);
var
Y: Integer;
MaxHeight: Integer;
X: Integer;
R: TRect;
TxtHeight: Integer;
begin
for Y := AGrid.FixedRows to AGrid.RowCount - 1 do
begin
MaxHeight := AGrid.DefaultRowHeight - 4;
for X := AGrid.FixedCols to AGrid.ColCount - 1 do
begin
R := Rect(0, 0, AGrid.ColWidths[X] - 4, 0);
TxtHeight := DrawText(AGrid.Canvas.Handle, PChar(AGrid.Cells[X, Y]), -1,
R, DT_WORDBREAK or DT_CALCRECT);
if TxtHeight > MaxHeight then
MaxHeight := TxtHeight;
end;
AGrid.RowHeights[Y] := MaxHeight + 4;
end;
end;
There are also other StringGrid components able of drawing multiline text. For instance, this one which I wrote myself (download source: NLDStringGrid) with possibly this result:
var
R: TRect;
begin
NLDStringGrid1.Columns.Add;
NLDStringGrid1.Columns.Add;
NLDStringGrid1.Cells[1, 1] := 'Sample test'#13#10'Second line';
NLDStringGrid1.Columns[1].MultiLine := True;
NLDStringGrid1.AutoRowHeights := True;
SetRect(R, 2, 2, 3, 3);
NLDStringGrid1.MergeCells(TGridRect(R), True, True);
NLDStringGrid1.ColWidths[2] := 40;
NLDStringGrid1.Cells[2, 2] := 'Sample test'#13#10'Second line';
end;

Answer 2

The TStringGrid's default renderer don't support multiple lines. By setting the TStringGrid in OwnerDraw mode (by invoking the OnDrawCell event) you can render each cell by your own liking.
Have a look at this for an example that helped a previous user.
Linked reference code inserted:
procedure DrawSGCell(Sender : TObject; C, R : integer; Rect : TRect;
Style : TFontStyles; Wrap : boolean; Just : TAlignment;
CanEdit : boolean);
{ draws formatted contents in string grid cell at col C, row R;
Style is a set of fsBold, fsItalic, fsUnderline and fsStrikeOut;
Wrap invokes word wrap for the cell's text; Just is taLeftJustify,
taRightJustify or taCenter; if CanEdit false, cell will be given
the background color of fixed cells; call this routine from
grid's DrawCell event }
var
S : string;
DrawRect : TRect;
begin
with (Sender as tStringGrid), Canvas do begin
{ erase earlier contents from default drawing }
if (R >= FixedRows) and (C >= FixedCols) and CanEdit then
Brush.Color:= Color
else
Brush.Color:= FixedColor;
FillRect(Rect);
{ get cell contents }
S:= Cells[C, R];
if length(S) > 0 then begin
case Just of
taLeftJustify : S:= ' ' + S;
taRightJustify : S:= S + ' ';
end;
{ set font style }
Font.Style:= Style;
{ copy of cell rectangle for text sizing }
DrawRect:= Rect;
if Wrap then begin
{ get size of text rectangle in DrawRect, with word wrap }
DrawText(Handle, PChar(S), length(S), DrawRect,
dt_calcrect or dt_wordbreak or dt_center);
if (DrawRect.Bottom - DrawRect.Top) > RowHeights[R] then begin
{ cell word-wraps; increase row height }
RowHeights[R]:= DrawRect.Bottom - DrawRect.Top;
SetGridHeight(Sender as tStringGrid);
end
else begin
{ cell doesn't word-wrap }
DrawRect.Right:= Rect.Right;
FillRect(DrawRect);
case Just of
taLeftJustify : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_wordbreak or dt_left);
taCenter : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_wordbreak or dt_center);
taRightJustify : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_wordbreak or dt_right);
end;
end
end
else
{ no word wrap }
case Just of
taLeftJustify : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_singleline or dt_vcenter or dt_left);
taCenter : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_singleline or dt_vcenter or dt_center);
taRightJustify : DrawText(Handle, PChar(S), length(S), DrawRect,
dt_singleline or dt_vcenter or dt_right);
end;
{ restore no font styles }
Font.Style:= [];
end;
end;
end;
I think this will work fine for you...