Delphi …hide the scrollbars of a DBGrid?
Posted by jpluimers on 2021/05/04
Recently I needed a plain TDBGrid without a horizontal scrollbar. I based it on the below solutions, but using an interposer class (type TDBGrid = class(TDBGrid) ... end;).
Another solution is to redirect the WinProc for a single grid component to a different method (you can apply it to the similar TDBCtrlGrid class as well):
unit DBGridFormUnit; uses Winapi.Messages, Vcl.DBGrids, Vcl.Forms; type TDBGridForm = class(TForm) DBGrid: TDBGrid; procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); strict private OriginalDBGridWindowProc : TWndMethod; procedure DBGridWindowProc(var Message: TMessage); end; implementation uses Winapi.Windows; procedure TDBGridForm.FormCreate(Sender: TObject); begin OriginalDBGridWindowProc := DBGrid.WindowProc; DBGrid.WindowProc := DBGridWindowProc; end; procedure TDBGridForm.FormDestroy(Sender: TObject); begin DBGrid.WindowProc := OriginalDBGridWindowProc; end; procedure TDBGridForm.DBGridWindowProc(var Message: TMessage); const ScrollStylesToExclude = WS_VSCROLL or WS_HSCROLL; var Style: Integer; begin if Message.Msg = WM_NCCALCSIZE then begin Style := GetWindowLong(Handle, GWL_STYLE); if (Style and ScrollStylesToExclude) <> 0 then // any scroll style to exclude present? SetWindowLong(Handle, GWL_STYLE, Style and not ScrollStylesToExclude); end else OrigWndProc(Message); end; end.
I think the SwissDelphiCenter solution in [WayBack] …hide the scrollbars of a DBGrid? originally has been copied from the 2003 post by Peter Below at [WayBack] how to hide DBCtrlGrid scrollbars – delphi.
(* Q: I want to hide the vertical scrollbar on a dbgrid when the record count exceed a number. How can I do that? A: Make a descendent of the TDBGrid class. Add a handler for the WM_NCCALCSIZE message. Title: ...hide the scrollbars of a DBGrid? Author: P. Below Category: VCL *) type TNoScrollDBGrid = class(TDBGrid) private procedure WMNCCalcSize(var Msg: TMessage); message WM_NCCALCSIZE; end; procedure TNoScrollDBGrid.WMNCCalcSize(var Msg: TMessage); const Scrollstyles = WS_VSCROLL or WS_HSCROLL; var Style: Integer; begin Style := GetWindowLong(Handle, GWL_STYLE); if (Style and Scrollstyles) <> 0 then SetWindowLong(Handle, GWL_STYLE, Style and not Scrollstyles); inherited; end; //This removes both scrollbars. If you want to remove only the vertical one //change the scrollstyles constant accordingly.
I like this derived class from [WayBack] Delphi VCL Component • View topic • Hiding Scrollbars in DBGRID by Chris Luck based on the code from Peter Below more (I slightly condensed it from non-relevant code):
unit NoScrollDBGrid; interface uses Windows, Messages, DBGrids; type TNoScrollDBGrid = class(TDBGrid) private FVertScroll: Boolean; FHorzScroll: Boolean; procedure WMNCCalcSize(var msg: TMessage); message WM_NCCALCSIZE; procedure SetVertScroll(Value: Boolean); procedure SetHorzScroll(Value: Boolean); published property VertScroll: Boolean read FVertScroll write SetVertScroll; property HorzScroll: Boolean read FHorzScroll write SetHorzScroll; end; procedure Register; implementation uses Classes; procedure TNoScrollDBGrid.SetVertScroll(Value: Boolean); begin if FVertScroll <> Value then begin FVertScroll := Value; RecreateWnd; end; end; procedure TNoScrollDBGrid.SetHorzScroll(Value: Boolean); begin if FHorzScroll <> Value then begin FHorzScroll := Value; RecreateWnd; end; end; procedure TNoScrollDBGrid.WMNCCalcSize(var msg: TMessage); var style: Integer; begin style := getWindowLong( handle, GWL_STYLE ); if (NOT(FHorzScroll)) AND ((style and WS_HSCROLL) <> 0) then SetWindowLong( handle, GWL_STYLE, style and not WS_HSCROLL ); if (NOT(FVertScroll)) AND ((style and WS_VSCROLL) <> 0) then SetWindowLong( handle, GWL_STYLE, style and not WS_VSCROLL ); inherited; end; procedure Register; begin RegisterComponents('Samples', [TNoScrollDBGrid]); end; end.
–jeroen
The Wiert Corner - irregular stream of stuff 
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