Title: DBGrid Component that show deleted and updated and inserted new records in diffrent colors.
Question: DBGrid Show all state of the related DataSet
Answer:
This component show state of the related data set of DBGrid and used for data base controlers.
it's appreciate to send any note or comment or suggestion to Vafaeija@yahoo.com
unit atcDBGrid;
(*
(c) Aveen Tech
2001 - 2002
FileName: atcDBGrid.pas
Version Date Author Comment
1.0 13/06/2000 Majid Vafai Jahan Create.
OVERVIEW
- This grid is inherited from DBGrid and add some required functionality to it.
Functionality:
- Record type are all records that may be modified, unmodified, inserted, deleted.
- Coloring according to Record type.
- show selected Record Type.
*)
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
Grids, DBGrids, dbTables, db;
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 );
RTL: array [Boolean] of Integer = (0, DT_RTLREADING);
type
TCachedShow = (csModify, csUnModify, csRemoved, csInserted, csAll, csNormal);
TatcDBGrid = class(TDBGrid)
private
FCachedShow: TCachedShow;
FModifiedColor: TColor;
FInsertedColor: TColor;
FDeletedColor: TColor;
procedure SetCachedShow(const Value: TCachedShow);
protected
procedure DrawDataCell(const Rect: TRect; Field: TField;
State: TGridDrawState); override;
procedure DrawColumnCell(const Rect: TRect; DataCol: Integer;
Column: TColumn; State: TGridDrawState); override;
public
constructor Create(AOwner: TComponent); override;
published
property atcCachedShow: TCachedShow read FCachedShow write SetCachedShow;
property atcDeletedColor: TColor read FDeletedColor write FDeletedColor;
property atcInsertedColor: TColor read FInsertedColor write FInsertedColor;
property atcModifiedColor: TColor read FModifiedColor write FModifiedColor;
end;
procedure Register;
implementation
(******************************************************************************)
procedure Register;
begin
RegisterComponents('ATC DB Compo', [TatcDBGrid]);
end;
(******************************************************************************)
constructor TatcDBGrid.Create(AOwner: TComponent);
(*
Description: Record Type Showing is All except Deletes.
*)
begin
inherited;
FCachedShow := csNormal;
FDeletedColor := clGray;
FInsertedColor := clAqua;
FModifiedColor := clRed;
end;
(******************************************************************************)
procedure TatcDBGrid.DrawColumnCell(const Rect: TRect; DataCol: Integer;
Column: TColumn; State: TGridDrawState);
(*
Description: On Drawing Column Color Updated Records.
*)
var
ARect: TRect;
begin
inherited;
if not Assigned(Column.Field) then
exit;
// Copy Rect into Variable.
CopyRect(ARect, Rect);
if Assigned(DataLink) and (DataLink.Active) and (DataLink.DataSet nil) then
begin
// if current record is modified
if DataLink.DataSet.UpdateStatus = usModified then
begin
Canvas.Brush.Color := atcModifiedColor;
Canvas.Font.Color := clBlack;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Column.Field.Text), Length(Column.Field.Text), ARect,
AlignFlags[Column.Alignment] or RTL[UseRightToLeftAlignmentForField(Column.Field, Column.Alignment)]);
end
// if current record is inserted.
else if DataLink.DataSet.UpdateStatus = usInserted then
begin
Canvas.Brush.Color := atcInsertedColor;
Canvas.Font.Color := clBlack;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Column.Field.Text), Length(Column.Field.Text), ARect,
AlignFlags[Column.Alignment] or RTL[UseRightToLeftAlignmentForField(Column.Field, Column.Alignment)]);
end
// if current record is deleted.
else if DataLink.DataSet.UpdateStatus = usDeleted then
begin
Canvas.Brush.Color := atcDeletedColor;
Canvas.Font.Color := clWhite;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Column.Field.Text), Length(Column.Field.Text), ARect,
AlignFlags[Column.Alignment] or RTL[UseRightToLeftAlignmentForField(Column.Field, Column.Alignment)]);
end;
end;
end;
(******************************************************************************)
procedure TatcDBGrid.DrawDataCell(const Rect: TRect; Field: TField;
State: TGridDrawState);
(*
Description: Draw Cell
*)
var
ARect: TRect;
begin
inherited;
CopyRect(ARect, Rect);
if Assigned(DataLink) and (DataLink.Active) and (DataLink.DataSet nil) then
begin
// if current record is modified.
if DataLink.DataSet.UpdateStatus = usModified then
begin
Canvas.Brush.Color := clRed;
Canvas.Font.Color := clBlack;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Field.Text), Length(Field.Text), ARect,
AlignFlags[Field.Alignment] or RTL[UseRightToLeftAlignmentForField(Field, Field.Alignment)]);
end
// if current record is inserted.
else if DataLink.DataSet.UpdateStatus = usInserted then
begin
Canvas.Brush.Color := clAqua;
Canvas.Font.Color := clBlack;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Field.Text), Length(Field.Text), ARect,
AlignFlags[Field.Alignment] or RTL[UseRightToLeftAlignmentForField(Field, Field.Alignment)]);
end
// if current record is deleted.
else if DataLink.DataSet.UpdateStatus = usDeleted then
begin
Canvas.Brush.Color := clGray;
Canvas.Font.Color := clWhite;
Canvas.FillRect(Rect);
DrawText(Canvas.Handle, PChar(Field.Text), Length(Field.Text), ARect,
AlignFlags[Field.Alignment] or RTL[UseRightToLeftAlignmentForField(Field, Field.Alignment)]);
end;
end;
end;
(******************************************************************************)
procedure TatcDBGrid.SetCachedShow(const Value: TCachedShow);
(*
Description: Record type for showing in grid.
Parameters: Value cached record show.
*)
begin
FCachedShow := Value;
if ComponentState = [csDesigning] then
exit;
if not Assigned(DataSource) or not Assigned(DataSource.DataSet) then
exit;
// for showing selected record type only.
if Assigned(DataLink) and Assigned(DataLink.DataSet) and (DataLink.Active) then
begin
case FCachedShow of
csAll:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtModified, rtInserted, rtDeleted, rtUnmodified];
csModify:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtModified];
csUnModify:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtUnmodified];
csInserted:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtInserted];
csRemoved:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtDeleted];
csNormal:
TBDEDataSet(DataSource.DataSet).UpdateRecordTypes := [rtModified, rtInserted, rtUnmodified];
end;
end;
end;
(******************************************************************************)
end.