public void keyPressed(KeyEvent e) {
				// TODO Auto-generated method stub
				if (e.getKeyCode() == KeyEvent.VK_ENTER
						&& textField.getText().compareTo("") != 0) {
					if (prefs.getSolutionType().compareTo(
							SolutionType.DETAILLED_SOLUTION) == 0)
						controller.simplify(SolutionType.DETAILLED_SOLUTION);
					else
						controller.simplify(SolutionType.MINIMIZED_FUNCTION);
				}

			}