Delphi-Quellcode:
procedure TForm3.Button4Click(Sender: TObject);
var
isOpened: Boolean;
begin
isOpened := TPresentationState.Opened in MultiView1.Presenter.State;
if isOpened then Caption := 'is opened' else Caption := 'is closed';
end;
Edit:
Du warst schneller. IsShowed, wtf. IsShown wenn schon.