日常随笔第十二弹－简单的音乐播放器

• 音乐播放器

import UIKit
import AVFoundation

enum Mode {//定义三种音乐播放模式
    case repeatSong
    case repeatOneSong
    case random
}

var playmd : Mode = .repeatSong//初始化播放模式


class ViewController: UIViewController, AVAudioPlayerDelegate {
    var audio : AVAudioPlayer?
    var times : NSTimer!
    var i = 0
    
    
    let url1 = ["Justin Bieber&Ludacris-Baby", "One Direction-Steal My Girl (Live Acoustic Session)", "Damien Rice&Lisa Hannigan-9 Crimes"]
    
    @IBOutlet weak var progressView: UIProgressView!
    
    //播放暂停键
    @IBAction func avaudio(sender: UIButton) {
        buttonPlayChangePause()
        play()
        
    }
    
    //下一首歌播放键
    
    
    @IBAction func nextplaying(sender: UIButton) {
        
        progressView.progress = 0
        switch playmd {
        case .random:
            i = Int(arc4random_uniform(UInt32(url1.count-1)))
            
        default:
            if(i >= url1.count-1){
                i = 0
                
            }
                
            else{
                i += 1
                
            }

        }
        playing()
        play()
    }
    
    
    //上一首歌播放键
    @IBAction func beforPlaying(sender: AnyObject) {
        progressView.progress = 0
        
        switch playmd {
        case .random:
            i = Int(arc4random_uniform(UInt32(url1.count-1)))
        default:
            if(i <= 0){
                i = url1.count-1
                
            }
                
            else{
                i -= 1
                
            }
            
        }
        playing()
        play()
    }
    
    
    
    //播放模式切换键
    @IBOutlet weak var changemd: UIButton!
    
    
    @IBAction func changeMode(sender: UIButton) {
        changemd.layer.cornerRadius = 5
        switch playmd {
        
        case .repeatSong:
            playmd = .repeatOneSong
            changemd.setImage(UIImage(named: "play_repeat_one"), forState: .Normal)
            
        case .repeatOneSong:
            playmd = .random
            changemd.setImage(UIImage(named: "play_random"), forState: .Normal)
            
        case .random:
            playmd = .repeatSong
            changemd.setImage(UIImage(named: "play_repeat"), forState: .Normal)
        }
        
        
    }
    
    
    
    //音量调节属性
    @IBOutlet weak var sound: UISlider!
    
    
    
    //播放按钮属性
    @IBOutlet weak var playbutton: UIButton!
    
    //背景图片
    @IBOutlet weak var backgroundImage: UIImageView!
    
    //歌名显示
    @IBOutlet weak var songsName: UILabel!
    
    //歌曲开始播放时间
    @IBOutlet weak var playingTime: UILabel!
    
    //歌曲总时间
    @IBOutlet weak var sumTime: UILabel!
    
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        sound.value = 0.1//音量调节按钮设置
        progressView.progress = 0//播放进度条初始化
        playing()
        audio?.pause()
        playbutton.selected = false
        
        
    }
    
    //AVAudioPlayerDelegate协议方法
    func audioPlayerDidFinishPlaying(player: AVAudioPlayer, successfully flag: Bool) {
        print("完成播放")
        
        //完成播放后自动跳到下一首（判断模式）
        switch playmd {
        case .repeatOneSong:
            audio?.numberOfLoops = -1
        case .repeatSong:
            if(i >= url1.count-1){
                i = 0
                
            }
                
            else{
                i += 1
                
            }

        default:
            i = Int(arc4random_uniform(UInt32(url1.count-1)))
        }
        playing()
    }
    
    //计时器方法：实现了进度条的同步和播放时间同步
    func didtime(times : NSTimer){
        progressView.progress = Float((audio?.currentTime)!/(audio?.duration)!)//计算进度条
        
        audio?.volume = sound.value
        
        playingTime.text = "\(Int((audio?.currentTime)!/60)):\(Int((audio?.currentTime)!%60/10))\(Int((audio?.currentTime)!%60%10))"//播放时间计算
        
        sumTime.text = "\(Int((audio?.duration)!/60)):\(Int((audio?.duration)!%60/10))\(Int((audio?.duration)!%60%10))"//音乐总时间计算
    }
    
    //开始播放音乐
    func playing(){
        
        let url = NSBundle.mainBundle().URLForResource(url1[i], withExtension: "mp3")//将资源url进行存储
        try! audio = AVAudioPlayer(contentsOfURL: url!)//传递url
        
        audio?.enableRate = true
        audio?.numberOfLoops = 0//设置循环播放
        audio?.rate = 1//设置播放速度
        audio?.prepareToPlay()
        audio?.play()
        songsName.text = url1[i]
        
        
        playbutton.selected = true
        audio?.delegate = self
        
    
    }
    
    //切换播放／暂停
    func buttonPlayChangePause() {
        playbutton.selected = !playbutton.selected
        
    }
    
    //判断是否播放
    func play() {
        if playbutton.selected == true{
            audio?.play()
            times = NSTimer.scheduledTimerWithTimeInterval(0.01, target: self, selector: #selector(didtime(_:)), userInfo: nil, repeats: true)
        }
        else{
            audio?.pause()
            times?.invalidate()
        }
        
    }

}