Swift学习笔记（0.1---循环按钮 ScrollView

循环按钮+ScrollView处理点击事件

目的：控制器的scroll联动上方按钮的

3EE620DD-1708-4798-857E-B8AC14C3FFEF.png

按钮的创建，这个按钮的多少取决与需求，可滑动那就搞个ScrollView，多个联动，不多说直接添代码

fileprivate func setupTitleView() {
        var currentHeight: CGFloat = 64
        if view.frame.height == iPhoneXHeight {
            currentHeight += iPhoneXTopHeight
        }
        let titleView = UIView(frame: CGRect(x: 0, y: currentHeight, width: view.frame.width, height: 35))
        titleView.backgroundColor = UIColor.init(white: 1.0, alpha: 0.7)
        view.addSubview(titleView)
        
        for i in 0..<titles.count {
            let button = UIButton(type: .custom)
            button.tag = 100 + i
            button.setTitle(titles[i], for: .normal)
            button.setTitleColor(UIColor.darkGray, for: .normal)
            button.setTitleColor(UIColor.red, for: .disabled)
            button.titleLabel?.font = UIFont.systemFont(ofSize: 14)
            button.addTarget(self, action: #selector(clickTitleView(_:)), for: .touchUpInside)
            let width = titleView.frame.width / CGFloat(titles.count)
            let height = titleView.frame.height
            button.frame = CGRect(x: CGFloat(i) * width, y: 0, width: width, height: height - 2)
//            button.layoutIfNeeded() //不能立即获取button的label的frame 需要强制布局
            titleView.addSubview(button)
            if i == 0 {
                button.titleLabel?.sizeToFit()
                self.bottomView.frame = CGRect(x: 0, y: 0, width: button.titleLabel!.frame.width, height: 2)
                self.bottomView.center = CGPoint(x: button.center.x, y:button.frame.height + 1)
                titleView.addSubview(bottomView)
                clickTitleView(button)
            }
        }
    }

@objc fileprivate func clickTitleView(_ sender: UIButton) {
        currentButton.isEnabled = true
        currentButton = sender
        currentButton.isEnabled = false
        
        UIView.animate(withDuration: 0.25) {
            self.bottomView.frame = CGRect(x: 0, y: 0, width: self.currentButton.titleLabel!.frame.width, height: 2)
            self.bottomView.center = CGPoint(x: self.currentButton.center.x, y:self.currentButton.frame.height + 1)
        }
        
        var offSet = contentView.contentOffset
        offSet.x = CGFloat(sender.tag - 100) * contentView.frame.width
        contentView.setContentOffset(offSet, animated: true)
    }

UIScrollViewDelegate

extension ZYDEssenceViewController: UIScrollViewDelegate {
    
    func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
        scrollViewDidEndScrollingAnimation(scrollView)
        let index = scrollView.contentOffset.x / scrollView.frame.width
        clickTitleView(view.viewWithTag(100 + Int(index)) as! UIButton)
    }
    
    func scrollViewDidEndScrollingAnimation(_ scrollView: UIScrollView) {
        let index = scrollView.contentOffset.x / scrollView.frame.width
        let vc = childViewControllers[Int(index)]
        vc.view.frame = CGRect(x: index * contentView.frame.width, y: 0, width: contentView.frame.width, height: contentView.frame.height)
        contentView.addSubview(vc.view)
    }
}