Article #17056: Customizing TTrackBar

 Question and Answer Database
FAQ2056D.txt Customizing TTrackBar
Category :VCL
Platform :All
Product :All 32 bit
Question:
How can I create a trackbar where the track has a thin line on
which the slider moves along, rather than a rather big white
space which the slider moves along?
Answer:
The following example demonstrates creating a descendant of
the TTrackbar component that overrides the CreateParams
method, and clears the TBS_ENABLESELRANGE flag from the
params style. This results in a Trackbar component that has a
small thin track for the slider to move upon. Note that the
TBS_ENABLESELRANGE constant is declared in the CommCtrl unit.
Example:
uses CommCtrl, ComCtrls;
type TMyTrackBar = class(TTrackBar)
procedure CreateParams(var Params: TCreateParams); override;
end;
procedure TMyTrackBar.CreateParams(var Params: TCreateParams);
begin
inherited;
Params.Style := Params.Style and not TBS_ENABLESELRANGE;
end;
var
MyTrackbar : TMyTrackbar;
procedure TForm1.Button1Click(Sender: TObject);
begin
MyTrackBar := TMyTrackbar.Create(Form1);
MyTrackbar.Parent := Form1;
MyTrackbar.Left := 100;
MyTrackbar.Top := 100;
MyTrackbar.Width := 150;
MyTrackbar.Height := 45;
MyTrackBar.Visible := true;
end;
7/16/98 4:31:28 PM

Last Modified: 01-SEP-99