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)}