public void AddNewWave()
    {
        Wave newWave = new Wave();

        // create the first group with default settings
        newWave.AddNewGroup();

        waves.Add(newWave);
    }
    public void AddNewGroup()
    {
        if (wave.Groups.Count >= 6)
        {
            return;
        }

        wave.AddNewGroup();
        int lastElementIndex = wave.Groups.Count - 1;

        addGroupButton(wave.Groups[lastElementIndex], lastElementIndex);
        addPauseInputField(wave.Pauses[lastElementIndex], lastElementIndex);
    }