private void setProgram(LogoDocument program){
		Document document = programEditor.getDocument();
		if (document != null && document instanceof LogoDocument){
			((LogoDocument)document).removeLogoDocumentListener(this);
		}
		programEditor.setDocument(program);
		if (program != null){
			program.addLogoDocumentListener(this);
		}
		updateTitle();
	}