Youtube pan手势播放视频动画
2022-04-23 本文已影响0人
_浅墨_
效果：
全部代码：
//
// ViewController.swift
// catchtrans
//http://camendesign.com/code/video_for_everybody/test.html
import UIKit
import UIKit.UIGestureRecognizerSubclass
import AVFoundation
private enum State {
case closed, open
}
extension State {
var opposite: State {
switch self {
case .open:
return .closed
case .closed:
return .open
}
}
}
class ViewController: UIViewController {
private var animationProgress: CGFloat = 0
var transitionAnimator = UIViewPropertyAnimator()
private var currentState: State = .closed
private lazy var panRecognizer: InstantPanGestureRecognizer = {
let recognizer = InstantPanGestureRecognizer()
recognizer.addTarget(self, action: #selector(popupViewPanned(recognizer:)))
return recognizer
}()
lazy var thumbnailImageView: UIImageView = {
return UIImageView()
}()
lazy var popupView: UIView = {
let _popupView = UIView()
_popupView.backgroundColor = UIColor.gray
return _popupView
}()
var bottomConstraint = NSLayoutConstraint()
var popupOffset: CGFloat = 0
var viewHeight: CGFloat = 0
lazy var videoView: UIView = {
return UIView()
}()
let videoURLString: String = Bundle.main.path(forResource: "clip", ofType: "mp4")!
var url: URL {
return URL(fileURLWithPath: videoURLString)
}
lazy var asset: AVURLAsset = {
var asset: AVURLAsset = AVURLAsset(url: url)
return asset
}()
lazy var playerItem: AVPlayerItem = {
var playerItem: AVPlayerItem = AVPlayerItem(asset: self.asset)
return playerItem
}()
lazy var player: AVPlayer = {
var player: AVPlayer = AVPlayer(playerItem: self.playerItem)
player.actionAtItemEnd = .none
return player
}()
lazy var playerLayer: AVPlayerLayer = {
var playerLayer: AVPlayerLayer = AVPlayerLayer(player: self.player)
return playerLayer
}()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
viewHeight = view.frame.size.height
popupOffset = viewHeight - CGFloat(60)
layout()
popupView.addGestureRecognizer(panRecognizer)
}
func layout() {
popupView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(popupView)
popupView.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
popupView.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
bottomConstraint = popupView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: popupOffset)
bottomConstraint.isActive = true
popupView.heightAnchor.constraint(equalToConstant: viewHeight).isActive = true
popupView.addSubview(videoView)
videoView.translatesAutoresizingMaskIntoConstraints = false
videoView.backgroundColor = UIColor.white
videoView.leadingAnchor.constraint(equalTo: popupView.leadingAnchor, constant: 30).isActive = true
videoView.trailingAnchor.constraint(equalTo: popupView.trailingAnchor, constant: -30).isActive = true
videoView.topAnchor.constraint(equalTo: popupView.topAnchor, constant: 60).isActive = true
NSLayoutConstraint(item: videoView, attribute: .height, relatedBy: .equal, toItem: videoView, attribute: .width, multiplier: 1, constant: 0).isActive = true
popupView.addSubview(thumbnailImageView)
thumbnailImageView.translatesAutoresizingMaskIntoConstraints = false
thumbnailImageView.backgroundColor = UIColor.white
thumbnailImageView.leadingAnchor.constraint(equalTo: popupView.leadingAnchor, constant: 15).isActive = true
thumbnailImageView.topAnchor.constraint(equalTo: popupView.topAnchor, constant: 10).isActive = true
thumbnailImageView.heightAnchor.constraint(equalToConstant: 40).isActive = true
thumbnailImageView.widthAnchor.constraint(equalToConstant: 40).isActive = true
thumbnailImageView.contentMode = .scaleAspectFit
videoView.layer.insertSublayer(playerLayer, at: 0)
thumbnailImageView.image = getThumbnailImage()
}
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
playerLayer.frame = videoView.bounds
}
@objc func popupViewPanned(recognizer: UIPanGestureRecognizer) {
switch recognizer.state {
case .began:
if player.isPlaying {
player.pause()
}
thumbnailImageView.alpha = 0
animateTransition(to: currentState.opposite, duration: 2)
transitionAnimator.pauseAnimation()
animationProgress = transitionAnimator.fractionComplete
case .changed:
let translation = recognizer.translation(in: popupView)
var fraction = -translation.y / popupOffset
if currentState == .open { fraction *= -1 }
if transitionAnimator.isReversed { fraction *= -1 }
transitionAnimator.fractionComplete = fraction + animationProgress
case .ended:
let yVelocity = recognizer.velocity(in: popupView).y
let shouldClose = yVelocity > 0
if yVelocity == 0 {
transitionAnimator.continueAnimation(withTimingParameters: nil, durationFactor: 0)
break
}
switch currentState {
case .open:
if !shouldClose && !transitionAnimator.isReversed { transitionAnimator.isReversed = !transitionAnimator.isReversed }
if shouldClose && transitionAnimator.isReversed { transitionAnimator.isReversed = !transitionAnimator.isReversed }
case .closed:
if shouldClose && !transitionAnimator.isReversed { transitionAnimator.isReversed = !transitionAnimator.isReversed }
if !shouldClose && transitionAnimator.isReversed { transitionAnimator.isReversed = !transitionAnimator.isReversed }
}
transitionAnimator.continueAnimation(withTimingParameters: nil, durationFactor: 0)
default:
()
}
}
private func animateTransition(to state: State, duration: TimeInterval) {
if transitionAnimator.isRunning { return }
transitionAnimator = UIViewPropertyAnimator(duration: duration, dampingRatio: 1.0, animations: {
switch state {
case .open:
self.bottomConstraint.constant = 0
case .closed:
self.bottomConstraint.constant = self.popupOffset
}
self.view.layoutIfNeeded()
})
transitionAnimator.addCompletion { (position) in
switch position {
case .start:
self.currentState = state.opposite
case .end:
self.currentState = state
case .current:
()
@unknown default:
break
}
switch self.currentState {
case .open:
self.bottomConstraint.constant = 0
self.player.play()
case .closed:
self.bottomConstraint.constant = self.popupOffset
self.thumbnailImageView.transform = CGAffineTransform(scaleX: 1.2, y: 1.2)
UIView.animate(withDuration: 0.2, animations: {
self.thumbnailImageView.transform = CGAffineTransform.identity
self.thumbnailImageView.alpha = 1.0
})
}
}
transitionAnimator.startAnimation()
}
func getThumbnailImage() -> UIImage? {
let assetImgGenerate = AVAssetImageGenerator(asset: asset)
assetImgGenerate.appliesPreferredTrackTransform = true
let time = CMTimeMakeWithSeconds(Float64(5), preferredTimescale: 600)
do {
let img = try assetImgGenerate.copyCGImage(at: time, actualTime: nil)
let thumbnail = UIImage(cgImage: img)
return thumbnail
} catch {
return nil
}
}
}
extension AVPlayer {
var isPlaying: Bool {
return (rate != 0 && (error == nil))
}
}
class InstantPanGestureRecognizer: UIPanGestureRecognizer {
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
if (self.state == UIGestureRecognizer.State.began) { return }
super.touchesBegan(touches, with: event)
self.state = UIGestureRecognizer.State.began
}
}
