AVAudioPlayer mp3文件无法播放

Question

我是一名业余开发人员，正在开发一个ios应用程序，该应用程序包含当按下按钮时正在播放的声音文件（mp3）。 但是，声音没有播放（在移动设备上测试，而不是在ios模拟器上测试）。 我已经在捆绑资源中有了声音文件，并添加了AVFoundation以将二进制文件与库链接。 我有xcode 4.6，有mac osx 10.8.4。 这是我的viewcontroller.h代码：

#import <UIKit/UIKit.h>
#import <RevMobAds/RevMobAds.h>
#import <AVFoundation/AVFoundation.h>


@interface ViewController : UIViewController 


- (IBAction)playButton:(id)sender;
- (IBAction)stopButton:(id)sender;

@property (nonatomic, strong) AVAudioPlayer *avPlayer;

- (void)revmob;
@end

Viewcontroller.m：

#import "ViewController.h"
#import <RevMobAds/RevMobAds.h>


@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    [[RevMobAds session] showBanner];
    // Do any additional setup after loading the view, typically from a nib.
    NSString *stringPath = [[NSBundle mainBundle] pathForResource:@"98648__dobroide__20100606-mosquito" ofType:@"mp3"];
    if (stringPath) 
    {
        NSURL *url = [NSURL fileURLWithPath:stringPath];

        NSError *error;

       _avPlayer = [[AVAudioPlayer alloc]initWithContentsOfURL:url error:&error];
        if (!error) 
        {
            [_avPlayer setNumberOfLoops:-1];
        } 
        else  
        {
            NSLog(@"Error occurred: %@", [error localizedDescription]);
        }
    } 
    else 
    {
        NSLog(@"Resource not found");
    }
    [self performSelector:@selector(revmob) withObject:nil afterDelay:10.0];
}

- (void)revmob 
{
    [[RevMobAds session] showFullscreen];
}
- (IBAction)playButton:(id)sender 
{
    [_avPlayer play];
    NSLog(@"Sound playing");
}

- (IBAction)stopButton:(id)sender 
{
    [_avPlayer pause];
    NSLog(@"Sound Stopped");
}
@end

Answer 1

在ViewController.h中，导入AVFoundation头文件：#import

转到ViewController.m，并在接口部分中添加以下出口属性和IBAction方法定义：

@interface ViewController () 

@property (nonatomic, strong) IBOutlet UILabel *trackTitle;
@property (nonatomic, strong) IBOutlet UILabel *playedTime;

- (IBAction)stopSound:(id)sender; 
- (IBAction)playOrPauseSound:(id)sender;

@end

返回ViewController.xib并进行以下连接：

顶部标签-> trackTitle出口

中间标签->播放时间出口

左键-> IBAction播放或暂停声音

右键-> IBAction stopSound

现在建立连接，我们可以在ViewController.m中完成代码。 在界面部分，添加以下属性

@property (nonatomic, strong) AVAudioPlayer *audioPlayer;
@property (nonatomic) BOOL isPlaying; 
@property (nonatomic, strong) NSTimer *timer;

转到ViewController.m，并在接口部分中添加以下出口属性和IBAction方法定义。

@interface ViewController () 

@property (nonatomic, strong) IBOutlet UILabel *trackTitle;
@property (nonatomic, strong) IBOutlet UILabel *playedTime;

- (IBAction)stopSound:(id)sender; 
- (IBAction)playOrPauseSound:(id)sender;

@end

在中更改viewDidLoad方法：

- (void)viewDidLoad 
{ 
  [super viewDidLoad];

  self.view.backgroundColor = [UIColor whiteColor];
  self.isPlaying = NO; 
  self.trackTitle.text = @"The Stone Foxes - EveryBody Knows";

  NSBundle *mainBundle = [NSBundle mainBundle]; 
  NSString *filePath = [mainBundle pathForResource:@"thestonefoxes-everybodyknows" ofType:@"mp3"]; 
  NSData *fileData = [NSData dataWithContentsOfFile:filePath];

  NSError *error = nil;

  self.audioPlayer = [[AVAudioPlayer alloc] initWithData:fileData error:&error] 
    [self.audioPlayer prepareToPlay]; 
}


- (IBAction)playOrPauseSound:(id)sender; 
{ 
  if (self.isPlaying)
  { 
    // Music is currently playing 
    [self.audioPlayer pause]; 
    self.isPlaying = NO; 
  } 
  else 
  { 
    // Music is currenty paused/stopped 
    [self.audioPlayer play]; 
    self.isPlaying = YES;

    self.timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateTime) userInfo:nil repeats:YES]; 
  } 
}

- (void)updateTime 
{ 
  NSTimeInterval currentTime = self.audioPlayer.currentTime;

  NSInteger minutes = floor(currentTime/60);
  NSInteger seconds = trunc(currentTime - minutes * 60);

  // update your UI with currentTime; 
  self.playedTime.text = [NSString stringWithFormat:@"%d:%02d", minutes, seconds]; 
}

- (IBAction)stopSound:(id)sender 
{ 
  [self.audioPlayer stop];
  self.audioPlayer.currentTime = 0; 
  self.isPlaying = NO; 
}

Answer 2

我已经在Mac上测试了您的代码，它似乎可以正常工作。 可能是造成问题的原因是，虽然mp3在Xcode中可见，但在编译过程中并未将其添加到捆绑软件中。 喜欢这个问题 。

要修复此问题，请单击Xco​​de中的mp3，查看“文件检查器”，然后选中目标旁边的“目标成员身份”框（在屏幕截图中，我的屏幕截图是SOTest）。