override func viewDidLoad() {  super.viewDidLoad()  // 替換 tabbar  let _tabBar = TabBar()  // 監(jiān)聽按鈕點(diǎn)擊事件  _tabBar.handleBtnReleaseClick(self, action: #selector(btnReleaseClick))  setValue(_tabBar, forKey: "tabBar")}

// MARK: 刪除占位“按鈕”，添加自定義按鈕override func layoutSubviews() {  super.layoutSubviews()  btnRelease.backgroundColor = UIColor.white  // 過濾掉 _UIBarBackground 類型的對(duì)象，只保留 UITabBarButton 類型的對(duì)象  let tabbarButtonList = iews.filter{NSStringFromClass(type(of: $0)) == abBarButton"}  // 取出需要?jiǎng)h除的“按鈕”（經(jīng)測(cè)試，知道中間那個(gè)加號(hào)按鈕的下標(biāo)是2）  let tmpView = tabbarButtonList[safe: 2]  // 把默認(rèn)生成的從父容器中移除  tmpView?.removeFromSuperview()  let x = (InnerConst.ScreenW - btnRelease.w) * 0.5  let y = InnerConst.ButtonOffsetY  btnRelease.origin = CGPoint(x: x, y: y)  addSubview(btnRelease)}

// MARK: 處理默認(rèn)情況下，按鈕超出 TabBar 以外區(qū)域不能點(diǎn)擊問題override func hitTest(_ point: CGPoint, with event: UIEvent?) -View? {  if isHidden == false {    let newPoint = convert(point, to: btnRelease)    if btnRelease.point(inside: newPoint, with: event) {      return btnRelease    }    return super.hitTest(point, with: event)  }  return super.hitTest(point, with: event)}

func handleBtnReleaseClick(_ target: AnyObject?, action: Selector) {  btnRelease.addTarget(target, action: action, for: .touchUpInside)}