Title: Simple context-sensitive help
Question: I am creating a not so big application and I want to give the users a context-sensitive help without creating a big windows helpsystem or using all kind of tools
Answer:
Most of the times its overkill to use tools to create a real Windows-Helpsystem for smaller applications. However, often youd like to give the user some help besides a printed manual.
Here is a small example of the way I do it:
Create a new application with 2 forms. The second form will be the Help-form in this example. On the second form is a RichEdit-control called RedHelp with the ReadOnly-property on True and the OnKeyUp-event of RedHelp is implemented as follows:
procedure TForm2.redHelpKeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
if key = VK_ESCAPE then close;
end;
For the first form I set the KeyPreview-property on True and I placed three components on the form as example.
Of course there are other ways and more sofisticated ways to do this, but I wanted to keep it simple.
The complete code of Unit1 is here below:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls, ExtCtrls;
type
TForm1 = class(TForm)
Edit1: TEdit;
Memo1: TMemo;
RadioGroup1: TRadioGroup;
procedure FormKeyUp(Sender: TObject; var Key: Word;
Shift: TShiftState);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
uses Unit2;
{$R *.DFM}
procedure TForm1.FormKeyUp(Sender: TObject; var Key: Word;
Shift: TShiftState);
var dir, s, HelpFile : string;
begin
if key = VK_F1 then //if a F1 is pressed
begin
s := Form1.ActiveControl.Name; //look which control is active
if s = '' then //when e.g. an item off a RadioGroup is active
s := Form1.ActiveControl.Parent.Name;
if s = '' then s := Application.ExeName; //always get something
dir := ExtractFilePath(Application.ExeName);//get the applications-directory
HelpFile := format('%s%s.rtf',[dir, s]); //make the complete filename
if FileExists(HelpFile) then //if it's exists, load it
begin
Form2.redHelp.Lines.LoadFromFile(HelpFile);
Form2.Show;
end else //if it's not there, create it
begin
Form2.redHelp.Lines.Clear;
Form2.redHelp.Lines.Add(format('Help for %s-control', [s]));
Form2.redHelp.Lines.Add('Add your helptext here');
Form2.redHelp.Lines.SaveToFile(HelpFile);
end;
end;
end;
end.