AVAudioPlayer音频播放

AVAudioPlayer类创建的实例可以看作为一个音频播放器,可以播放来自文件或存储的音频数据。
它支持多种音频格式,而且能够进行进度、音量、播放速度等控制。
使用这个类,可以:
1、在指定的时间开始播放音频
2、从文件或内存缓冲区播放音频
3、循环播放

 

属性 描述
@property(readonly, getter=isPlaying) BOOL playing 是否正在播放,只读
@property float volume 音量大小,范围0~1.0
@property float pan 立体声,-1.0完全左声道,0.0左右声道平衡,1.0完全右声道
@property float rate 播放速率,范围0.5~2.0,1.0时为正常播放,如果需要更改播放速率必须设置enableRate为YES
@property BOOL enableRate 是否可以更改播放速率
@property NSInteger numberOfLoops 重复播放次数,为0时只播放一次,小于0时为无限播放,大于0时表示循环次数
@property(readonly) NSDictionary *settings 音频播放次数信息,只读
@property(readonly) NSUInteger numberOfChannels 与音频播放器相关联的声音通道的数量。(只读)
@property(nonatomic, copy) NSArray *channelAssignments 与音频播放器相关AVAudioSessionChannelDescription对象数组
@property(readonly) NSTimeInterval duration 播放时长
@property NSTimeInterval currentTime 当前播放时长
@property(readonly) NSTimeInterval deviceCurrentTime 输出设备播放音频的时间,注意如果播放中被暂停此时间也会继续累加
@property(readonly) NSURL *url 音频文件路径,只读
@property(readonly) NSData *data 音频数据,只读
@property(getter=isMeteringEnabled) BOOL meteringEnabled 否启用音频测量,默认为NO,一旦启用音频测量可以通过updateMeters方法更新测量值
对象方法 描述
- (instancetype)initWithContentsOfURL:(NSURL *)url  error:(NSError **)outError 使用文件URL初始化播放器,注意这个URL不能是HTTP URL,AVAudioPlayer不支持加载网络媒体流,只能播放本地文件
- (instancetype)initWithData:(NSData *)data error:(NSError **)outError

使用NSData初始化播放器,注意使用此方法时必须文件格式和文件后缀一致,否则出错,所以相比此方法更推荐使用上述方法

或- (instancetype)initWithData:(NSData *)data fileTypeHint:(NSString *)utiString error:(NSError **)outError方法进行初始化

- (BOOL)play 播放音频文件
- (BOOL)playAtTime:(NSTimeInterval)time 在指定的时间开始播放音频
- (void)pause 暂停播放
- (void)stop 停止播放
- (BOOL)prepareToPlay 将音频文件加载到缓冲区
- (float)averagePowerForChannel:(NSUInteger)channelNumber 获得指定声道的分贝平均值,注意如果要获得分贝平均值必须在此之前调用updateMeters方法
- (float)peakPowerForChannel:(NSUInteger)channelNumber 获得指定声道的分贝峰值,注意如果要获得分贝峰值必须在此之前调用updateMeters方法
- (void)updateMeters 更新音频测量值,注意如果要更新音频测量值必须设置meteringEnabled为YES,通过音频测量值可以即时获得音频分贝等信息
代理方法 说明
- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag 播放完成后调用,在这里可以进行一些属性的设置
- (void)audioPlayerDecodeErrorDidOccur:(AVAudioPlayer *)player error:(NSError *)error 音频解码发生错误

AVAudioPlayer的使用比较简单:

1、初始化AVAudioPlayer对象,通常指定本地文件路径

2、设置播放器属性,例如播放次数,音量大小,设置代理等

3、开始播放,调用play方法

下面就是AVAudioPlayer实现的一个简单播放器,它播放本地的音频文件,实现了播放、暂停、显示播放进度,现实播放时间等功能:

  1 #import "JZViewController.h"
  2 #import <AVFoundation/AVFoundation.h>
  3 
  4 @interface JZViewController() <AVAudioPlayerDelegate>
  5 
  6 @property (nonatomic, strong) AVAudioPlayer * audioPlayer;
  7 @property (nonatomic, strong) UIImageView * imageView;
  8 @property (nonatomic, strong) UIProgressView * progressView;
  9 @property (nonatomic, strong) UILabel * timeLabel;
 10 @property (nonatomic, strong) UILabel * currenttimeLabel;
 11 @property (nonatomic, assign) NSTimer * timer;
 12 @property (nonatomic, assign) int intTime;
 13 @property (nonatomic, assign) int timeNum;
 14 @property (nonatomic, assign) UIButton * button;
 15 
 16 @end
 17 
 18 @implementation JZViewController
 19 
 20 - (void)viewDidLoad
 21 {
 22     [super viewDidLoad];
 23     self.title = @"礼物"; //播放音频为 礼物.mp3 钢琴曲
 24     self.view.backgroundColor = [UIColor whiteColor];
 25     
 26     [self.view addSubview:self.imageView];
 27     
 28     [self initView];
 29 }
 30 
 31 //界面初始化,添加一个view、一个进度条、3个label、一个button
 32 - (void)initView
 33 {
 34     UIView * view = [[UIView alloc] initWithFrame:CGRectMake(0, [UIScreen mainScreen].bounds.size.height - 150, [UIScreen mainScreen].bounds.size.width, 150)];
 35     view.backgroundColor = [UIColor colorWithRed:246 / 255.0 green:246 / 255.0 blue:246 / 255.0 alpha:0.9];
 36     view.alpha = 0.8f;
 37     [self.view addSubview:view];
 38 
 39     UIProgressView * progressView = [[UIProgressView alloc] initWithFrame:CGRectMake(40, 50, [UIScreen mainScreen].bounds.size.width - 80, 0)];
 40     self.progressView = progressView;
 41     [view addSubview:progressView];
 42     
 43     UILabel * timeLabel = [[UILabel alloc] initWithFrame:CGRectMake([UIScreen mainScreen].bounds.size.width - 40, 40, 40, 20)];
 44     timeLabel.backgroundColor = [UIColor clearColor];
 45     timeLabel.font = [UIFont systemFontOfSize:11];
 46     timeLabel.textAlignment = NSTextAlignmentCenter;
 47     self.timeLabel = timeLabel;
 48     [view addSubview:timeLabel];
 49     
 50     UILabel * currentTimeLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 40, 40, 20)];
 51     currentTimeLabel.backgroundColor = [UIColor clearColor];
 52     currentTimeLabel.font = [UIFont systemFontOfSize:11];
 53     currentTimeLabel.textAlignment = NSTextAlignmentCenter;
 54     self.currenttimeLabel = currentTimeLabel;
 55     [view addSubview:currentTimeLabel];
 56     
 57     UILabel * label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, 50)];
 58     label.backgroundColor = [UIColor clearColor];
 59     label.text = @"礼物";
 60     label.textAlignment = NSTextAlignmentCenter;
 61     [view addSubview:label];
 62     
 63     UIButton * button = [[UIButton alloc] initWithFrame:CGRectMake([UIScreen mainScreen].bounds.size.width / 2 - 30, 70, 60, 60)];
 64     button.backgroundColor = [UIColor clearColor];
 65     [button setImage:[UIImage imageNamed:@"start.jpg"] forState:UIControlStateNormal];
 66     [button addTarget:self action:@selector(clickButton:) forControlEvents:UIControlEventTouchUpInside];
 67     self.button = button;
 68     button.tag = 10;
 69     [view addSubview:button];
 70 }
 71 
 72 //初始化imageView,添加背景图片
 73 - (UIImageView *)imageView
 74 {
 75     if(!_imageView){
 76         UIImage * image = [UIImage imageNamed:@"sjz.jpg"];
 77         UIImageView * imageView = [[UIImageView alloc] initWithImage:image];
 78         imageView.frame = [UIScreen mainScreen].bounds;
 79         _imageView = imageView;
 80     }
 81     return _imageView;
 82 }
 83 
 84 //懒加载,创建audioPlayer
 85 - (AVAudioPlayer *)audioPlayer
 86 {
 87     if(!_audioPlayer){
 88         NSString * urlStr = [[NSBundle mainBundle] pathForResource:@"礼物.mp3" ofType:nil];
 89         NSURL * url = [NSURL fileURLWithPath:urlStr];
 90         NSError * error = nil;
 91         _audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
 92         //设置播放属性
 93         _audioPlayer.numberOfLoops = 0;
 94         _audioPlayer.delegate = self;
 95         [_audioPlayer prepareToPlay];  //加载音频文件到缓存
 96         
 97         
 98         if(error){
 99             NSLog(@"初始化播放器过程发生错误,错误信息:%@", error.localizedDescription);
100             return nil;
101         }
102         
103     }
104     return _audioPlayer;
105 }
106 
107 //点击button后调用的方法,播放、暂停音乐
108 - (void)clickButton:(UIButton *)sender
109 {
110     if(sender.tag == 10){
111         sender.tag = 20;
112         [sender setImage:[UIImage imageNamed:@"stop.jpg"] forState:UIControlStateNormal];
113         [self.audioPlayer play];
114         self.timer.fireDate = [NSDate distantPast];
115     }else{
116         sender.tag = 10;
117         [sender setImage:[UIImage imageNamed:@"start.jpg"] forState:UIControlStateNormal];
118         [self.audioPlayer pause];
119         self.timer.fireDate = [NSDate distantFuture];
120     }
121 }
122 
123 //初始化定时器
124 - (NSTimer *)timer
125 {
126     if(!_timer){
127         _timer = [NSTimer scheduledTimerWithTimeInterval:1.0f target:self selector:@selector(updateTimeAddProgress) userInfo:nil repeats:YES];
128         self.timeNum = (int)self.audioPlayer.duration;
129     }
130     return _timer;
131 }
132 
133 //定时器的调用方法,在这里更新进度条,并且更新时间
134 - (void)updateTimeAddProgress
135 {
136     float progress = self.audioPlayer.currentTime / self.audioPlayer.duration;
137     [self.progressView setProgress:progress animated:YES];
138     
139     self.intTime++;
140     NSString * str = [NSString stringWithFormat:@"%.2d:%.2d", self.intTime / 60, self.intTime % 60];
141     self.currenttimeLabel.text = str;
142     
143     self.timeNum--;
144     NSString * strTime = [NSString stringWithFormat:@"%.2d:%.2d", self.timeNum / 60, self.timeNum % 60];
145     self.timeLabel.text = strTime;
146 }
147 
148 //代理方法,做一些播放完成后的处理,删除掉定时器,button图片的更改、停止音乐播放等
149 - (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag
150 {
151     self.intTime = 0;
152     [self.audioPlayer stop];
153     [self.timer invalidate];
154     self.timer = nil;
155     
156     self.button.tag = 10;
157     [self.button setImage:[UIImage imageNamed:@"start.jpg"] forState:UIControlStateNormal];
158 }
159 
160 @end

 

posted @ 2015-08-18 10:32  sjzLovecj  阅读(4334)  评论(0编辑  收藏  举报