Советы по Delphi


Хочу шапку в TDBGrid. Как сделать?


Nomadic советует:

Уже реализовано в виде вот этого компонента - © Andre

    unit bdbgrid;

interface

uses

Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, Grids, DBGrids, Math;



type
TOnDrawTitleEvent = procedure(ACol : integer; ARect : TRect; var TitleText : string) of object;

TBitDBGrid = class(TDBGrid)
private
FBitmapBrowse : TBitmap;
FBitmapEdit : TBitmap;
FBitmapInsert : TBitmap;
FBitmapFill : TBitmap;
FRealTitleFont : TFont;
FOnDrawTitle : TOnDrawTitleEvent;
FResizeFlag : boolean;
{ Private declarations }
procedure SetRealTitleFont(Value : TFont);
procedure UpdateTitlesHeight;
protected
procedure
DrawCell(ACol, ARow: Longint; ARect: TRect; AState: TGridDrawState); override;
procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer); override;
procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer); override;
{ Protected declarations }
public
constructor
Create(AOwner : TComponent);override;
destructor Destroy; override;
{ Public declarations }
published
property
OnDrawTitle : TOnDrawTitleEvent read FOnDrawTitle write FOnDrawTitle;
property RealTitleFont : TFont read FRealTitleFont write SetRealTitleFont;
{ Published declarations }
end;

procedure Register;

implementation

var

DrawBitmap : TBitmap;

function Max(X, Y: Integer): Integer;
begin
Result := Y;
if X > Y then Result := X;
end;

procedure WriteText(ACanvas: TCanvas; ARect: TRect; DX, DY: Integer; const Text: string; Alignment: TAlignment);
// © Borland function :)
const
AlignFlags : array [TAlignment] of Integer =
( DT_LEFT or DT_WORDBREAK or DT_EXPANDTABS or DT_NOPREFIX,
DT_RIGHT or DT_WORDBREAK or DT_EXPANDTABS or DT_NOPREFIX,
DT_CENTER or DT_WORDBREAK or DT_EXPANDTABS or DT_NOPREFIX );
var
B, R: TRect;
I, Left: Integer;
begin
with
DrawBitmap, ARect do { Use offscreen bitmap to eliminate flicker and }
begin { brush origin tics in painting / scrolling. }
Width := Max(Width, Right - Left);
Height := Max(Height, Bottom - Top);
R := Rect(DX, DY, Right - Left - 1, Bottom - Top - 1);
B := Rect(0, 0, Right - Left, Bottom - Top);
end;
with DrawBitmap.Canvas do
begin

DrawBitmap.Canvas.CopyRect(B, ACanvas, ARect);
Font := ACanvas.Font;
Font.Color := ACanvas.Font.Color;
Brush := ACanvas.Brush;
SetBkMode(Handle, TRANSPARENT);
DrawText(Handle, PChar(Text), Length(Text), R,
AlignFlags[Alignment]);
end;
ACanvas.CopyRect(ARect, DrawBitmap.Canvas, B);
end;

constructor TBitDBGrid.Create(AOwner : TComponent);
begin
inherited
Create(Aowner);
FRealTitleFont := TFont.Create;
FResizeFlag := false;
end;

destructor TBitDBGrid.Destroy;
begin
FRealTitleFont.Free;
inherited Destroy;
end;

procedure TBitDBGrid.UpdateTitlesHeight;
var
Loop : integer;
MaxTextHeight : integer;
RRect : TRect;
begin
MaxTextHeight := 0;
for loop := 0 to Columns.Count - 1 do
begin

RRect := CellRect(0, 0);
RRect.Right := Columns[Loop].Width;
RRect.Left := 0;
Canvas.Font := RealTitleFont;
MaxTextHeight := Max(MaxTextHeight, DrawText(Canvas.Handle,
PChar(Columns[Loop].Title.Caption),
Length(Columns[Loop].Title.Caption), RRect,
DT_CALCRECT + DT_WORDBREAK)
);
end;
if TitleFont.Height <> - MaxTextHeight then
TitleFont.Height := - MaxTextHeight;
end;

procedure TBitDBGrid.MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
if
MouseCoord(X, Y).Y = 0 then
FResizeFlag := true;
inherited MouseDown(Button, Shift, X, Y);
end;

procedure TBitDBGrid.MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
inherited
MouseUp(Button, Shift, X, Y);
if FResizeFlag then begin
FResizeFlag := false;
UpdateTitlesHeight;
end;
end;

procedure TBitDBGrid.DrawCell(ACol, ARow: Longint; ARect: TRect; AState: TGridDrawState);
var
Indicator : TBitmap;
TitleText : string;
Al : TAlignment;
begin
if not
((gdFixed in AState) and ((ARow = 0) and (dgTitles in Options) and (ACol <> 0))) then
inherited
DrawCell(ACol, ARow, ARect, AState)
else
begin
if
DefaultDrawing then
begin
DrawEdge(Canvas.Handle, ARect, BDR_RAISEDINNER, BF_BOTTOMLEFT);
DrawEdge(Canvas.Handle, ARect, BDR_RAISEDINNER, BF_TOPRIGHT);
InflateRect(ARect, -1, -1);
Canvas.Brush.Color := FixedColor;
Canvas.FillRect(ARect);
end;
TitleText := Columns[ACol - 1].Title.Caption;
if Assigned(OnDrawTitle) then OnDrawTitle(ACol, ARect, TitleText);
if DefaultDrawing and (TitleText <> '') then
begin

Canvas.Brush.Style := bsClear;
Canvas.Font := RealTitleFont;
if ACol > 0 then Al := Columns[ACol - 1].Title.Alignment
else Al := Columns[0].Title.DefaultAlignment;
WriteText(Canvas, ARect, 2, 2, TitleText, Al);
end;
end;
end;

procedure TBitDBGrid.SetRealTitleFont(Value : TFont);
begin
FRealTitleFont.Assign(Value);
Repaint;
end;

procedure Register;
begin
RegisterComponents('Andre VCL', [TBitDBGrid]);
end;

initialization
DrawBitmap := TBitmap.Create;

finalization
DrawBitmap.Free;

end.

[001288]



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