Help please with Radio-group. 2

[delphiman]

I have the following radio group which reacts to a BitBtn.
I would prefer to replace the BitBtn with (perhaps) a
re-iterating procedure. Whereby mere selection of a
radio button has the desired effect.

Other than replacing the Radio Buttons with buttons, along with an eventhandler for each, I can't find how to do this.

Can someone please make a suggestion?

procedure TfrmRegister.BitBtn1Click(Sender: TObject);
begin
with RadioGroup1, Items do
begin
if Strings[ItemIndex] = 'Option1' then
begin
Panel2.Visible := False;
Panel3.Visible := False;
Panel1.Visible := True;
end;
if Strings[ItemIndex] = 'Option2 then
begin
Panel1.Visible := False;
Panel3.Visible := False;
Panel2.Visible := True;
end;
if Strings[ItemIndex] = 'Option3 then
begin
Panel1.Visible := False;
Panel2.Visible := False;
Panel3.Visible := True;
end;
end;
end;

 

[Punchinello]

If I understand what you want to do, then you should be able to remove the BitBtn altogether and add the following code to the RadioGroup1.OnClick event:

procedure TfrmRegister.RadioGroup1Click(Sender: TObject);
begin
  Panel1.Visible := (RadioGroup1.ItemIndex = 0);
  Panel2.Visible := (RadioGroup1.ItemIndex = 1);
  Panel3.Visible := (RadioGroup1.ItemIndex = 2);
end;

The OnClick event of a RadioGroup responds to any change to the selected item (RadioGroup.ItemIndex) including use of the arrow keys to change the selection.

The previous example assumes that your text 'Option1' is the first element (ItemIndex = 0) of the RadioGroup and that 'Option2' is second (ItemIndex = 1) and 'Option3' is third (ItemIndex = 2). However, if you wanted the code to reflect each item's text value, it would look like this:

procedure TfrmRegister.RadioGroup1Click(Sender: TObject);
begin
  with RadioGroup1 do begin
    Panel1.Visible := (Items[ItemIndex] = 'Option1');
    Panel2.Visible := (Items[ItemIndex] = 'Option2');
    Panel3.Visible := (Items[ItemIndex] = 'Option3');
  end;
end;

Good Luck!

 

[towerbase]

If you had a lot of panels or whatever and they were given the same name as the buttons in your RadioGroup then the following code, based on dhoernig above, would be more concise:

procedure TForm1.RadioGroup1Click(Sender: TObject);
var
  rg: integer;
  name: string;
  control: TControl;
begin
  for rg := 0 to radiogroup1.items.count - 1 do begin
    control := FindComponent ( radiogroup1.items[rg] ) as TControl;
    control.visible := btn.name = radiogroup1.items [ radiogroup1.itemindex ];
  end;
end;

Note that I've used TControl which allows the same code to be used for Panels, Buttons, Edit boxes and so on. They wouldn't all have to be the same type providing they inherited from TControl.

Andrew

 

[Punchinello]

Andrew, I think you mean:

[tt]control.visible := control.name = radiogroup1.items [ radiogroup1.itemindex ];[/tt]

Just trying to keep you on your toes!

Dave

 

[towerbase]

Yes, you're quite right, Dave. I tested it out using buttons and manually changed the code.

I should test amended code before posting it.
I should test amended code before posting it.
I should test amended code before posting it.
I should test amended code before posting it.
I should test amended code before posting it.
...

Do they still do lines as a punishment in schools these days?

Andrew