@Test
    public void textFieldIntegerTest() {
        when(focusEvent.getSource()).thenReturn(view.getNumberOfPointsTextField());
        when(focusEvent.getComponent()).thenReturn(view.getNumberOfPointsTextField());
        view.getNumberOfPointsTextField().setText("10");
        view.getNumberOfPointsTextField().getFocusListeners()[2].focusGained(focusEvent);
        view.getNumberOfPointsTextField().setText("11");
        view.getNumberOfPointsTextField().getFocusListeners()[2].focusLost(focusEvent);
        assertEquals(propertyName, MainWindowController.NUMBER_OF_POINTS);
        assertEquals(oldValue, "10");
        assertEquals(newValue, "11");
    }