@Test
    public void textFieldDoubleTest() {
        when(focusEvent.getSource()).thenReturn(view.getTimeStepTextField());
        when(focusEvent.getComponent()).thenReturn(view.getTimeStepTextField());
        view.getTimeStepTextField().setText("0.1");
        view.getTimeStepTextField().getFocusListeners()[2].focusGained(focusEvent);
        view.getTimeStepTextField().setText("0.5");
        view.getTimeStepTextField().getFocusListeners()[2].focusLost(focusEvent);
        assertEquals(propertyName, MainWindowController.TIME_STEP);
        assertEquals(oldValue, "0.1");
        assertEquals(newValue, "0.5");
    }