详解iOS App中调用AVAudioPlayer播放音频文件的用法

#import "AppDelegate.h"
#import "FirstVC.h"
@implementation AppDelegate

- (void)dealloc
{
    [_window release];
    [super dealloc];
}

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
    // Override point for customization after application launch.
   
    FirstVC *firstVC = [[FirstVC alloc] init];
    self.window.rootViewController = firstVC;
    [firstVC release];
   
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    //初始化三个button
    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button setFrame:CGRectMake(100, 100, 60, 40)];
    [button setTitle:@"Play" forState:UIControlStateNormal];
    [button addTarget:self action:@selector(play) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];
   
    UIButton *button1 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button1 setFrame:CGRectMake(100, 150, 60, 40)];
    [button1 setTitle:@"pause" forState:UIControlStateNormal];
    [button1 addTarget:self action:@selector(pause) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button1];
   
    UIButton *button2 = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [button2 setFrame:CGRectMake(100, 200, 60, 40)];
    [button2 setTitle:@"stop" forState:UIControlStateNormal];
    [button2 addTarget:self action:@selector(stop) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button2];
   
    //从budle路径下读取音频文件　　轻音乐 - 萨克斯回家 这个文件名是你的歌曲名字,mp3是你的音频格式
    NSString *string = [[NSBundle mainBundle] pathForResource:@"轻音乐 - 萨克斯回家" ofType:@"mp3"];
    //把音频文件转换成url格式
    NSURL *url = [NSURL fileURLWithPath:string];
    //初始化音频类 并且添加播放文件
    avAudioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:nil];
    //设置代理
    avAudioPlayer.delegate = self;
   
    //设置初始音量大小
   // avAudioPlayer.volume = 1;
   
    //设置音乐播放次数  -1为一直循环
    avAudioPlayer.numberOfLoops = -1;
   
    //预播放
    [avAudioPlayer prepareToPlay];
   
    //初始化一个播放进度条
    progressV = [[UIProgressView alloc] initWithFrame:CGRectMake(20, 50, 200, 20)];
    [self.view addSubview:progressV];
    [progressV release];
   
    //用NSTimer来监控音频播放进度
    timer = [NSTimer scheduledTimerWithTimeInterval:0.1 target:self
                                                     selector:@selector(playProgress)
                                                     userInfo:nil repeats:YES];
    //初始化音量控制
    volumeSlider = [[UISlider alloc] initWithFrame:CGRectMake(20, 70, 200, 20)];
    [volumeSlider addTarget:self action:@selector(volumeChange)
                       forControlEvents:UIControlEventValueChanged];
    //设置最小音量
    volumeSlider.minimumValue = 0.0f;
    //设置最大音量
    volumeSlider.maximumValue = 10.0f;
    //初始化音量为多少
    volumeSlider.value = 5.0f;
   
    [self.view addSubview:volumeSlider];
    [volumeSlider release];

    //声音开关控件(静音)
    UISwitch *swith = [[UISwitch alloc] initWithFrame:CGRectMake(100, 20, 60, 40)];
    [swith addTarget:self action:@selector(onOrOff:) forControlEvents:UIControlEventValueChanged];
    //默认状态为打开
    swith.on = YES;
    [self.view addSubview:swith];
    [swith  release];
}

//播放
- (void)play
{ 
    [avAudioPlayer play];
}
    //暂停
- (void)pause
{
    [avAudioPlayer pause];
}
    //停止
- (void)stop
{
    avAudioPlayer.currentTime = 0;  //当前播放时间设置为0
    [avAudioPlayer stop];
}
//播放进度条
- (void)playProgress
{
    //通过音频播放时长的百分比,给progressview进行赋值;
    progressV.progress = avAudioPlayer.currentTime/avAudioPlayer.duration;
}
//声音开关(是否静音)
- (void)onOrOff:(UISwitch *)sender
{
    avAudioPlayer.volume = sender.on;
}

//播放音量控制
- (void)volumeChange
{
   avAudioPlayer.volume = volumeSlider.value;
}

//播放完成时调用的方法  (代理里的方法),需要设置代理才可以调用
- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag
{
    [timer invalidate]; //NSTimer暂停   invalidate  使...无效;
}

- (void)dealloc
{
    [avAudioPlayer release];
    [progressV release];
    [volumeSlider release];
    [timer release];
    [super dealloc];
}

NSString *urlStr = @"http://…………xxx.mp3"; 
NSURL *url = [[NSURL alloc]initWithString:urlStr]; 
NSData * audioData = [NSData dataWithContentsOfURL:url]; 
 
//将数据保存到本地指定位置          
NSString *docDirPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]; 
NSString *filePath = [NSString stringWithFormat:@"%@/%@.mp3", docDirPath , @"temp"]; 
[audioData writeToFile:filePath atomically:YES]; 
       
//播放本地音乐           
NSURL *fileURL = [NSURL fileURLWithPath:filePath]; 
player = [[AVAudioPlayer alloc] initWithContentsOfURL:fileURL error:nil]; 
[player play];

[[AVAudioSession sharedInstance]setCategory:AVAudioSessionCategoryPlaybackerror:nil];