Mega Code Archive
Synchronize the Scrolling of two TStringgrids
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Title: synchronize the Scrolling of two TStringgrids?
{1.}
unit SyncStringGrid;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
Dialogs, Grids;
type
TSyncKind = (skBoth, skVScroll, skHScroll);
TSyncStringGrid = class(TStringGrid)
private
FInSync: Boolean;
FsyncGrid: TSyncStringGrid;
FSyncKind: TSyncKind;
{ Private declarations }
procedure WMVScroll(var Msg: TMessage); message WM_VSCROLL;
procedure WMHScroll(var Msg: TMessage); message WM_HSCROLL;
protected
{ Protected declarations }
public
{ Public declarations }
procedure DoSync(Msg, wParam: Integer; lParam: Longint); virtual;
published
{ Published declarations }
property SyncGrid: TSyncStringGrid read FSyncGrid write FSyncGrid;
property SyncKind: TSyncKind read FSyncKind write FSyncKind default skBoth;
end;
procedure Register;
implementation
procedure Register;
begin
RegisterComponents('Samples', [TSyncStringGrid]);
end;
procedure TSyncStringGrid.WMVScroll(var Msg: TMessage);
begin
if not FInSync and
Assigned(FSyncGrid) and
(FSyncKind in [skBoth, skVScroll]) then
FSyncGrid.DoSync(WM_VSCROLL, Msg.wParam, Msg.lParam);
inherited;
end;
procedure TSyncStringGrid.WMHScroll(var Msg: TMessage);
begin
if not FInSync and
Assigned(FSyncGrid) and
(FSyncKind in [skBoth, skHScroll]) then
FSyncGrid.DoSync(WM_HSCROLL, Msg.wParam, Msg.lParam);
inherited;
end;
procedure TSyncStringGrid.DoSync(Msg, wParam: Integer; lParam: Longint);
begin
FInSync := True;
Perform(Msg, wParam, lParam);
FinSync := False;
end;
end.
{****************************************}
{2.}
private
OldGridProc1, OldGridProc2: TWndMethod;
procedure Grid1WindowProc(var Message: TMessage);
procedure Grid2WindowProc(var Message: TMessage);
public
{...}
procedure TForm1.Grid1WindowProc(var Message: TMessage);
begin
OldGridProc1(Message);
if ((Message.Msg = WM_VSCROLL) or (Message.Msg = WM_HSCROLL) or
Message.msg = WM_Mousewheel)) then
begin
OldGridProc2(Message);
end;
end;
procedure TForm1.Grid2WindowProc(var Message: TMessage);
begin
OldGridProc2(Message);
if ((Message.Msg = WM_VSCROLL) or (Message.Msg = WM_HSCROLL) or
(Message.msg = WM_Mousewheel)) then
begin
OldGridProc1(Message);
end;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
OldGridProc1 := StringGrid1.WindowProc;
OldGridProc2 := StringGrid2.WindowProc;
StringGrid1.WindowProc := Grid1WindowProc;
StringGrid2.WindowProc := Grid2WindowProc;
end;
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