一直觉得自己写的不是技术，而是情怀，一个个的教程是自己这一路走来的痕迹。靠专业技能的成功是最具可复制性的，希望我的这条路能让你们少走弯路，希望我能帮你们抹去知识的蒙尘，希望我能帮你们理清知识的脉络，希望未来技术之巅上有你们也有我。

整个的原理在视频中已经说的很清楚了,不懂的话直接看视频是很明朗的.

前言

2023.09.03自定义封装一个视频拖拽的滚动条.需要满足一下的需求:
1.能拖拽快进
2.能点击快进
3.能预加载进度
4.显示当前播放进度
5.显示节点,点击跳到对应的节点

思路

该拖拽进度条底部是用来显示预加载进度的,使用系统自带的UIProgressView控件.最外面能拖拽播放进度的使用系统自带的UISlider控件.节点通过for循环创建按键出来的节点.这样有一个问题,当播放到节点的位置的时候,节点会挡住拖拽进度条的位置.所以拖拽进度条的原点,就用一张透明的图片(相当于不要了),然后创建一个按键在最前面,用一张圆形图片,挡住原来UISlider控件的原点,跟随滑动,播放的个过程

可以看到上面的图片就是用一个自定义的按键挡住了原来UISlider控件的原点.

重点

下面说一下整个封装的几个关键地方.

点击滚动条

算出point值的公式:

let point = ((pointTapped.x - positionOfSlider.x) * CGFloat(slider.maximumValue) / widthOfSlider)

全部代码

//
//  PlayProgressView.swift
//  SwiftDemol
//
//  Created by 冯汉栩 on 2023/8/21.
//

import UIKit

class PlayProgressView: UIView {
    
    // 预加载进度
    lazy var progress: UIProgressView = {
        let progress = UIProgressView()
        progress.progressTintColor = UIColor(red: 169.0/255.0, green: 169.0/255.0, blue: 169.0/255.0, alpha: 1.0)//深灰色
        progress.trackTintColor = UIColor(red: 228.0/255.0, green: 228.0/255.0, blue: 228.0/255.0, alpha: 1.0)//浅灰色
        return progress
    }()
    
    // 进度条 clearn_point   slider_pointer_normal
    lazy var slider: UISlider = { [weak self] in
        let slider  = UISlider()
        slider.minimumTrackTintColor = UIColor(red: 74.0/255.0, green: 155.0/255.0, blue: 234.0/255.0, alpha: 1.0)//蓝色
        slider.maximumTrackTintColor = UIColor.clear // 透明颜色
        slider.setThumbImage(UIImage(named: "slider_pointer_normal"), for: .normal)//clearn_point(透明) slider_pointer_normal(白色)
        slider.setThumbImage(UIImage(named: "slider_pointer_normal"), for: .highlighted)
        slider.setThumbImage(UIImage(named: "slider_pointer_normal"), for: .selected)
        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(sliderTapped(gestureRecognizer:)))
        slider.addGestureRecognizer(tapGestureRecognizer)
        return slider
    }()
    //自定义point点
    lazy private var draggableButton: UIButton = {
        let button = UIButton()
        button.frame = CGRect(x: 0, y: 0, width: 10, height: 20)
        //button.backgroundColor = .blue.withAlphaComponent(0.5)
        button.setImage(UIImage(named: "slider_pointer_normal"), for: .normal)
        button.tag = 111
        return button
    }()
    
    // 修改播放进度
    var changePointBlock:((_ point: Float) ->Void)?
    // point数组
    var pointList = [Float]()
    // 当前播放点的移动位置
    var pointX:Float = 0.0 {
        didSet {
            let newX = (self.frame.width - draggableButton.frame.width) * CGFloat(pointX)
            if newX.isNaN { return }
            draggableButton.frame = CGRect(x: newX, y: draggableButton.frame.origin.y, width: draggableButton.frame.width, height: draggableButton.frame.height)
            
            slider.value = pointX
        }
    }
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        buildUI()
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
        
    }
    
    private func buildUI() {
        backgroundColor = .clear // .green.withAlphaComponent(0.5)
        
        addSubview(progress)
        progress.snp.makeConstraints { make in
            make.centerY.equalToSuperview()
            make.left.equalToSuperview().offset(2+1)//2是跟随slider的2+偏移1
            make.right.equalToSuperview().offset(-2)
            make.height.equalTo(4)
        }
        
        addSubview(slider)
        slider.snp.makeConstraints { make in
            make.centerY.equalToSuperview().offset(-1)
            make.left.equalToSuperview().offset(2)
            make.right.equalToSuperview().offset(-2)
            make.height.equalTo(20)
        }
        
        
        addSubview(draggableButton)
        let panGesture = UIPanGestureRecognizer(target: self, action: #selector(handlePanGesture(_:)))
        draggableButton.addGestureRecognizer(panGesture)
    }
    
    override func layoutSubviews() {
        super.layoutSubviews()
        
        //严重的bug是否创建过
        if pointList.isEmpty { return }
        //如果有节点就移除
        for subview in self.subviews {
            if subview is UISlider {
                for sliderSubView in subview.subviews {
                    if sliderSubView is UIButton {
                        sliderSubView.removeFromSuperview()
                    }
                }
            }
        }
        //布局节点
        for i in 0..<pointList.count {
            let button = UIButton()
            slider.addSubview(button)
            button.tag = i
            button.setImage(UIImage(named: "point_none"), for: .normal)
            button.addTarget(self, action: #selector(pointNoneClick), for: .touchUpInside)
            button.snp.makeConstraints { make in
                make.width.equalTo(16)
                make.height.equalTo(20)
                make.centerY.equalToSuperview().offset(1)
                make.left.equalToSuperview().offset(Float(progress.bounds.size.width)*pointList[i]-16*0.5)
            }
        }
  
    }
    
    // MARK: - slider -- 点击滚动条
    @objc private func sliderTapped(gestureRecognizer: UIGestureRecognizer) {
        let pointTapped: CGPoint = gestureRecognizer.location(in: self)
        let positionOfSlider: CGPoint = slider.frame.origin
        let widthOfSlider: CGFloat = slider.frame.size.width
        let point = ((pointTapped.x - positionOfSlider.x) * CGFloat(slider.maximumValue) / widthOfSlider)
  
        //UI--修改进度条的值
        slider.setValue(Float(point), animated: false)
        
        //换算x的值
        let newX = (self.frame.width - draggableButton.frame.width) * CGFloat(point)
        //修改自定义point按键的frame
        draggableButton.frame = CGRect(x: newX, y: draggableButton.frame.origin.y, width: draggableButton.frame.width, height: draggableButton.frame.height)
        
        //闭包出去修改AVPlayer的值 0 -- 100
        changePointBlock?(Float(point))
    }
    
    // MARK: - 按键 -- 节点按键
    @objc private func pointNoneClick(button:UIButton) {
        //换算x的值
        let newX = (self.frame.width - draggableButton.frame.width) * CGFloat(pointList[button.tag])
        //修改自定义point按键的frame
        draggableButton.frame = CGRect(x: newX, y: draggableButton.frame.origin.y, width: draggableButton.frame.width, height: draggableButton.frame.height)
        //UI--修改进度条的值
        slider.setValue(Float(pointList[button.tag]), animated: false)
        //闭包出去修改AVPlayer的值 0 -- 100
        changePointBlock?(pointList[button.tag])
    }
    
    // MARK: - 自定义按键 -- 拖拽
    @objc func handlePanGesture(_ gesture: UIPanGestureRecognizer) {
        let translation = gesture.translation(in: self)
        //translation.x 拖拽的值
        var newX = draggableButton.frame.origin.x + translation.x
        switch gesture.state {
        case .changed:
            //更新按钮的 x 坐标，限制在 view 的范围内
            newX = max(0, min(newX, self.frame.width - draggableButton.frame.width))//意思是:newX取值范围0 ~ self.frame.width - draggableButton.frame.width 之间
            //修改自定义point按键的frame
            draggableButton.frame = CGRect(x: newX, y: draggableButton.frame.origin.y, width: draggableButton.frame.width, height: draggableButton.frame.height)
            gesture.setTranslation(.zero, in: self)
            //修改进度
            //换算成进度0.0-1.0
            let progress = newX / (self.frame.width - draggableButton.frame.width)
            //UI--修改进度条的值
            slider.setValue(Float(progress), animated: false)
            //闭包出去修改AVPlayer的值 0 -- 100
            changePointBlock?(Float(progress))
        default:
            break
        }
    }
    
}

使用

创建+返回值出来

约束

赋值给它