Swift tvOS如果用户单击播放/暂停

只是想弄清楚，在SwiftUI中，我如何知道用户是否单击了播放/暂停按钮

如果用户单击暂停/播放按钮，我需要媒体播放器暂停或播放

我见过这样的例子

override func pressesBegan(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {
  if(presses.first?.type == UIPressType.PlayPause) {
    pushedPlay()
    // don't call to super class 
    } 
}

斯威夫特音乐播放器

import SwiftUI
//import Foundation
import AVFoundation
import MediaPlayer
import AVKit

struct NowPlayingData: Codable, Identifiable {
    var id = UUID()
    var artist : String
    var song : String
    var cover : String
}

class MusicPlayer{
static let shared = MusicPlayer()
static var mediatype = ""
static var artist = ""
static var song = ""
static var cover = ""
static var uuid = UIDevice.current.identifierForVendor?.uuidString


var player: AVPlayer?
let playerViewController = AVPlayerViewController()

        
    func gettype(completion: @escaping (String) -> Void){
          
            completion(MusicPlayer.mediatype)
       
      }
    
    
        
      func getPodCastPlayerNP(completion: @escaping (NowPlayingData) -> ()) {
       // Timer.scheduledTimer(withTimeInterval: 15, repeats: true) { (timer) in
          let songdata = "{\"id\": \"1\",\"song\": \"\(MusicPlayer.song)\",\"artist\": \"\(MusicPlayer.artist)\", \"cover\": \"\(MusicPlayer.cover)\"}"
          let data: Foundation.Data = songdata.data(using: .utf8)!
          
          let podcast = try! JSONDecoder().decode(NowPlayingData.self, from: data)
                
                         //print(data!)
                        // let episode = podcast.programs
                        DispatchQueue.main.async{
                            // The array is stored under programs now
                          //print(podcast)
                          completion(podcast)
                        }
         // }
      }

    func startBackgroundMusic(url: String, type:String) {
     
        MusicPlayer.mediatype = String(type)
        
        //let urlString = "http://stream.radiomedia.com.au:8003/stream"
        let urlString = url+"?uuid="+MusicPlayer.uuid!
        print(urlString)
        guard let url = URL.init(string: urlString) else { return }

        let playerItem = AVPlayerItem.init(url: url)
        player = AVPlayer.init(playerItem: playerItem)
        
      
        do {

            try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [.duckOthers, .mixWithOthers, .allowAirPlay])
            print("Playback OK")
           // let defaults = UserDefaults.standard
           // defaults.set("1", forKey: defaultsKeys.musicplayer_connected)
            try AVAudioSession.sharedInstance().setActive(true)
            print("Session is Active")
        } catch {
           // let defaults = UserDefaults.standard
          //  defaults.set("0", forKey: defaultsKeys.musicplayer_connected)
            print(error)
        }

         #if targetEnvironment(simulator)

        self.playerViewController.player = player
        self.playerViewController.player?.play()
        print("SIMULATOR")

         #else

        self.setupRemoteTransportControls()
        player?.play()

        #endif
        

    }
    
    
    func startBackgroundMusicTwo() {

        
        let urlString = "http://stream.radiomedia.com.au:8003/stream"
        //let urlString = url
        guard let url = URL.init(string: urlString) else { return }

        let playerItem = AVPlayerItem.init(url: url)
        player = AVPlayer.init(playerItem: playerItem)
        
      
        do {

            try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default, options: [.duckOthers, .mixWithOthers, .allowAirPlay])
            print("Playback OK")
           // let defaults = UserDefaults.standard
           // defaults.set("1", forKey: defaultsKeys.musicplayer_connected)
            try AVAudioSession.sharedInstance().setActive(true)
            print("Session is Active")
        } catch {
           // let defaults = UserDefaults.standard
          //  defaults.set("0", forKey: defaultsKeys.musicplayer_connected)
            print(error)
        }

         #if targetEnvironment(simulator)

        self.playerViewController.player = player
        self.playerViewController.player?.play()
        print("SIMULATOR")

         #else

        self.setupRemoteTransportControls()
        player?.play()

        #endif

    }




func setupRemoteTransportControls() {
   // Get the shared MPRemoteCommandCenter
    let commandCenter = MPRemoteCommandCenter.shared()

    // Add handler for Play Command
    commandCenter.playCommand.addTarget { [unowned self] event in
        if self.player?.rate == 0.0 {
            self.player?.play()
            return .success
        }
        return .commandFailed
    }

    // Add handler for Pause Command
    commandCenter.pauseCommand.addTarget { [unowned self] event in
        if self.player?.rate == 1.0 {
            self.player?.pause()
            return .success
        }
        return .commandFailed
    }

   // self.nowplaying(artist: "Anna", song: "test")


}

func nowplaying(with artwork: MPMediaItemArtwork, artist: String, song: String){
  

MPNowPlayingInfoCenter.default().nowPlayingInfo = [
      MPMediaItemPropertyTitle:song,
      MPMediaItemPropertyArtist:artist,
      MPMediaItemPropertyArtwork: artwork,
      MPNowPlayingInfoPropertyIsLiveStream: true
]


   // self.getArtBoard();
}


func setupNowPlayingInfo(with artwork: MPMediaItemArtwork) {
      MPNowPlayingInfoCenter.default().nowPlayingInfo = [
        //   MPMediaItemPropertyTitle: "Some name",
        //   MPMediaItemPropertyArtist: "Some name",
           MPMediaItemPropertyArtwork: artwork,
           //MPMediaItemPropertyPlaybackDuration: CMTimeGetSeconds(currentItem.duration),
           //MPNowPlayingInfoPropertyPlaybackRate: 1,
           //MPNowPlayingInfoPropertyElapsedPlaybackTime: CMTimeGetSeconds(currentItem.currentTime())
       ]
   }



func getData(from url: URL, completion: @escaping (UIImage?) -> Void) {
    URLSession.shared.dataTask(with: url, completionHandler: {(data, response, error) in
        if let data = data {
            completion(UIImage(data:data))
        }
    })
        .resume()
}

func getArtBoard(artist: String, song: String, cover: String) {
   // MusicPlayer.JN = "[{'artist': \(artist), 'song':\(song), 'cover': \(cover)}]"
    MusicPlayer.artist = artist
    MusicPlayer.song = song
    MusicPlayer.cover = cover
    
    
    guard let url = URL(string: cover) else { return }
    getData(from: url) { [weak self] image in
        guard let self = self,
            let downloadedImage = image else {
                return
        }
        let artwork = MPMediaItemArtwork.init(boundsSize: downloadedImage.size, requestHandler: { _ -> UIImage in
            return downloadedImage
        })
        self.nowplaying(with: artwork, artist: artist, song: song)
    }
}



    func stopBackgroundMusic() {
        guard let player = player else { return }
        player.pause()

}
}

还尝试添加：

func onPlayPauseCommand(perform action: (() -> Void)?) -> ContentView{
    MusicPlayer.shared.player?.pause()
}

到我的内容视图，但它有一个错误

无法将类型为“Void”的返回表达式转换为返回类型为“ContentView”

**厄帕德**

因此，我尝试使用以下方法：

struct ContentView: View {
    @State var showingDetail = false
    
    @State var showDetail = String(false)
    var body: some View {
       
                            VStack{
                                
                                 Text("Interactive Radio").font(.headline).bold().multilineTextAlignment(.leading)
                                 Text(showDetail)
                                                       
                                 Spacer()
                                                       
                           }
                         
                         
            
                            
        .onAppear {
         //   self.navigationViewStyle(StackNavigationViewStyle())
            MusicPlayer.shared.startBackgroundMusic(url: "http://url.com/stream", type: "radio")
            print(self.showingDetail)
               
        }
                            
        
        .onPlayPauseCommand(perform: {
            MusicPlayer.shared.player?.pause()
            
        })
    
    }
    

}

但是没有成功。我也试过长时间的新闻报道，但也没有成功

.onLongPressGesture(minimumDuration: 0.5, perform: {
                                print("hello")
                            })

**解决**

请注意，为什么下面的内容可以让它工作

//
//  ContentView.swift
//  DRN1
//
//  Created by Russell Harrower on 10/10/20.
//

import SwiftUI
import AVKit



struct ContentView: View {
    @State var showingDetail = false
    
    @State var showDetail = String(false)
    var body: some View {
       
                                    
                                    
        Button(action: {
            print("hello")
        }, label: {
            Text("Button")
        })
                          
                         
                         
            
                            
        .onAppear {
         //   self.navigationViewStyle(StackNavigationViewStyle())
            MusicPlayer.shared.startBackgroundMusic(url: "http://URL:8006/stream", type: "radio")
            print(self.showingDetail)
               
        }
                            
                       
        .onPlayPauseCommand(perform: {
            
            if(MusicPlayer.shared.player?.rate != 0)
            {
                MusicPlayer.shared.player?.pause()
            }
            else{
                MusicPlayer.shared.player?.play()
            }
        })
    
    }
    

}


struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}

---

tvOS上有一个特殊的视图修改器：onPlayPauseCommand（perform:），只需将其添加到ContentView中，并用播放/暂停代码传递一个闭包

struct ContentView: View {
    var body: some View {
        Text("Hello, world!")
        .focusable()
        .onPlayPauseCommand(perform: {
            print("hello")
        })
    }
}

请注意

.focusable（）

——视图需要焦点才能播放/暂停工作，因此如果视图没有按钮或其他可聚焦元素，则必须手动设置

.focusable（）

文件：

---

在tvOS上有一个特殊的视图修改器：onPlayPauseCommand（perform:），只需将其添加到ContentView中，并用播放/暂停代码将其关闭即可

struct ContentView: View {
    var body: some View {
        Text("Hello, world!")
        .focusable()
        .onPlayPauseCommand(perform: {
            print("hello")
        })
    }
}

请注意

.focusable（）

——视图需要焦点才能播放/暂停工作，因此如果视图没有按钮或其他可聚焦元素，则必须手动设置

.focusable（）

文件：

---

它是以什么方式崩溃的，在Xcode中显示了哪条错误消息？它只是带来了一个红色的X，不会运行脚本“红色X”，这是一个错误，不是崩溃，单击“红色X”Xcode将尝试解释问题。它是以什么方式崩溃的，在Xcode中显示了哪条错误消息？它只是带来了一个红色的X，不会运行脚本“red X”，这是一个错误，不是崩溃，点击“red X”Xcode会试图解释这个问题。嗨，Adam，很抱歉在这里听起来很愚蠢，但是在结构ContentView:View{}中，或者作为一个新函数，当我像func onPlayPauseCommand（perform action:（（）->Void）？->ContentView{MusicPlayer.shared.player？.pause（）那样添加它时它不起作用错误：无法将类型为“Void？”的返回表达式转换为返回类型“ContentView”，请在“body”中应用它，就像执行.onAppear（执行：）.onPlayPauseCommand（执行：{MusicPlayer.shared.player？.pause（）}）不起作用我甚至试着在它里面放一个打印-没有什么你可能需要在你的视图上设置

.focusable（）

——请参见上面的编辑Hi Adam，很抱歉这里听起来很愚蠢，但是在结构ContentView:view{}里面，或者作为一个新函数，当我添加它时，就像func onPlayPauseCommand（执行操作：（（）->Void）？->ContentView一样{MusicPlayer.shared.player？.pause（）}它不起作用错误：无法将类型为“Void？”的返回表达式转换为返回类型为“ContentView”，请在“body”中应用它，就像执行.onAppear（执行：）.onPlayPauseCommand（执行：{MusicPlayer.shared.player？.pause（））不起作用我甚至试着在它里面放一个打印-没有什么你可能需要在你的视图上设置

.focusable（）

——请参见上面的编辑

struct ContentView: View {
    var body: some View {
        Text("Hello, world!")
        .focusable()
        .onPlayPauseCommand(perform: {
            print("hello")
        })
    }
}