public override void Update(float dt)
    {
        foreach (KeyValuePair <Character, FloatingBar> pair in _floatingBars)
        {
            Character   ch  = pair.Key;
            FloatingBar bar = pair.Value;

            bar.UpdatePosition(ch.position + new Vector3(0, 2, 0));
        }
    }
    /// <summary>
    /// 角色出生
    /// </summary>
    /// <param name="ch"></param>
    public void OnCharacterCreate(Character ch)
    {
        FloatingBar bar = new FloatingBar(_transform, ch);

        _floatingBars.Add(ch, bar);
    }