在 iOS 中使用控件播放音频
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【中文标题】在 iOS 中使用控件播放音频【英文标题】：Playing audio with controls in iOS 【发布时间】：2011-11-23 08:39:02 【问题描述】：我用tab bar,nav bar and table view 制作了一个应用程序。
在表格视图中，您可以选择收听一些音频。
新视图打开，我有一些控件，例如：播放、暂停、音量滑块、进度滑块、带有当前时间的标签。
它有效，但并不完美。 我可以播放音频，可以暂停音频，也可以使用滑块向前或向后跳。但是现在：
当我点击导航栏上的后退按钮时，歌曲继续播放。没关系，但是当我再次返回视图时，计时器和滑块会自行重置。我无法暂停歌曲，只需等待它停止播放即可。
另外，当我点击播放时，返回表格视图，选择另一个文件播放，第一个文件不会停止播放。
这里是 Audio1DetailViewController.h 代码：
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
@interface Audio1DetailViewController: UIViewController <AVAudioPlayerDelegate>
IBOutlet UISlider *volumeControl;
IBOutlet UILabel *timerLabel;
IBOutlet UISlider *progressBar;
AVAudioPlayer *audioPlayer;
NSTimer *playbackTimer;
@property (nonatomic, retain) IBOutlet UISlider *volumeControl;
@property (nonatomic, retain) IBOutlet UILabel *timerLabel;
@property (nonatomic, retain) IBOutlet UISlider *progressBar;
@property (nonatomic, retain) NSTimer *playbackTimer;
@property (nonatomic, retain) AVAudioPlayer *audioPlayer;
-(IBAction) playAudio;
-(IBAction) stopAudio;
-(IBAction) adjustVolume;
-(IBAction) sliderChanged;
@end
这里是 Audio1DetailViewController.m 代码：
#import "Audio1DetailViewController.h"
@implementation Audio1DetailViewController
@synthesize volumeControl, timerLabel, playbackTimer, progressBar, audioPlayer;
-(void)playAudio
playbackTimer = [NSTimer scheduledTimerWithTimeInterval:1.0
target:self
selector:@selector(updateTime)
userInfo:nil
repeats:YES];
[audioPlayer play];
-(void)stopAudio
[playbackTimer invalidate];
[audioPlayer stop];
-(void)adjustVolume
if (audioPlayer != nil)
audioPlayer.volume = volumeControl.value;
-(void)updateTime
float minutes = floor(audioPlayer.currentTime/60);
float seconds = audioPlayer.currentTime - (minutes * 60);
float duration_minutes = floor(audioPlayer.duration/60);
float duration_seconds =
audioPlayer.duration - (duration_minutes * 60);
NSString *timeInfoString = [[NSString alloc]
initWithFormat:@"%0.0f.%0.0f / %0.0f.%0.0f",
minutes, seconds,
duration_minutes, duration_seconds];
timerLabel.text = timeInfoString;
[timeInfoString release];
- (void)viewDidLoad
[super viewDidLoad];
NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle]
pathForResource:@"001Fatiha"
ofType:@"MP3"]];
NSError *error;
audioPlayer = [[AVAudioPlayer alloc]
initWithContentsOfURL:url
error:&error];
[[AVAudiosession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
if (error)
NSLog(@"Error in audioPlayer: %@",
[error localizedDescription]);
else
audioPlayer.delegate = self;
[audioPlayer prepareToPlay];
playbackTimer = [NSTimer scheduledTimerWithTimeInterval:1 target:self
selector:@selector(updateSlider) userInfo:nil repeats:YES];
progressBar.maximumValue = audioPlayer.duration;
// Set the valueChanged target
[progressBar addTarget:self action:@selector(sliderChanged:) forControlEvents:
UIControl EventValueChanged];
- (void)updateSlider
// Update the slider about the music time
progressBar.value = audioPlayer.currentTime;
- (IBAction)sliderChanged:(UISlider *)sender
// Fast skip the music when user scroll the UISlider
[audioPlayer stop];
[audioPlayer setCurrentTime:progressBar.value];
[audioPlayer prepareToPlay];
[audioPlayer play];
-(void)audioPlayerDidFinishPlaying:
(AVAudioPlayer *)player successfully:(BOOL)flag
-(void)audioPlayerDecodeErrorDidOccur:
(AVAudioPlayer *)player error:(NSError *)error
-(void)audioPlayerBeginInterruption:(AVAudioPlayer *)player
-(void)audioPlayerEndInterruption:(AVAudioPlayer *)player
-(void)viewDidUnload
audioPlayer = nil;
volumeControl = nil;
-(void)dealloc
[audioPlayer release];
[volumeControl release];
[playbackTimer release];
[super dealloc];
@end
这里是 AudioTableViewController.h
#import <UIKit/UIKit.h>
@class Audio1DetailViewController;
@interface AudioTableViewController : UITableViewController
<UITableViewDelegate,UITableViewDataSource>
IBOutlet UITableView *audioTableView;
NSMutableArray *audioArray;
Audio1DetailViewController *audio1DetailViewController;
@property (nonatomic, retain) NSMutableArray *audioArray;
@property (nonatomic, retain) Audio1DetailViewController *audio1DetailViewController;
@end
还有 AudioTableViewController.m
#import "AudioTableViewController.h"
#import "Audio1DetailViewController.h"
#import "DEQAppDelegate.h"
@implementation AudioTableViewController
@synthesize audioArray;
@synthesize audio1DetailViewController;
- (id)initWithStyle:(UITableViewStyle)style
self = [super initWithStyle:style];
if (self)
// Custom initialization
return self;
- (void)didReceiveMemoryWarning
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
#pragma mark - View lifecycle
- (void)viewDidLoad
[super viewDidLoad];
self.title = NSLocalizedString(@"Audio", @"Audio");
self.audioArray = [[NSArray alloc] initWithObjects:
@"1. Het Begin", @"2. De Mensen", //etcetera
nil];
// Uncomment the following line to preserve selection between presentations.
self.clearsSelectionOnViewWillAppear = NO;
// Uncomment the following line to display an Edit button in the navigation bar for this
view controller.
// self.navigationItem.rightBarButtonItem = self.editButtonItem;
- (void)viewDidUnload
[super viewDidUnload];
// Release any retained subviews of the main view.
self.audioArray = nil;
- (void)viewWillAppear:(BOOL)animated
[super viewWillAppear:animated];
- (void)viewDidAppear:(BOOL)animated
[super viewDidAppear:animated];
- (void)viewWillDisappear:(BOOL)animated
[super viewWillDisappear:animated];
- (void)viewDidDisappear:(BOOL)animated
[super viewDidDisappear:animated];
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
#warning Potentially incomplete method implementation.
// Return the number of sections.
return 1;
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
#warning Incomplete method implementation.
// Return the number of rows in the section.
return [self.audioArray count];
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
cell = [[[UITableViewCell alloc] initWithStyle:
UITableViewCellStyleDefaultreuseIdentifier:CellIdentifier] autorelease];
// Configure the cell...
cell.textLabel.text = [self.audioArray objectAtIndex:[indexPath row]];
return cell;
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
// Navigation logic may go here. Create and push another view controller.
NSUInteger row = indexPath.row;
if (row == 0)
Audio1DetailViewController *audio1DetailViewController =[[Audio1DetailViewController alloc]
initWithNibName:@"Audio1DetailViewController" bundle:nil];
audio1DetailViewController.title = @"Audio";
[self.navigationController pushViewController:audio1DetailViewController animated:YES];
[audio1DetailViewController release];
if (row == 1)
//etcetera
- (void)dealloc
[audioArray release];
[super dealloc];
@end
【问题讨论】：
,还有See Apple Doc. 【参考方案1】：我建议您创建一个全局播放器对象。因为现在，每次你在导航控制器上推送这个视图时，你都会创建一个新视图。这也意味着您没有任何对前一个玩家的参考（并且无法阻止它）。所以：声明 AVAudioPlayer 更高一级（在表格视图中）。现在，当您选择其中的一行时，将其分配给这个新视图（您链接的那个）的一个属性。
您使用情节提要吗？然后你必须实现方法prepareForSegue:。在情节提要上为您的 segue 提供一个标识符（例如 showPlayer 并使用 if (segue.identifier isEqualToString:@"showPlayer") 检查）。
现在在您的viewDidLoad 中检查audioPlayer 是否为零。如果你
- (void)viewDidLoad
[super viewDidLoad];
if (audioPlayer == nil)
// your init (audioplayer =[[AVAudioPlayer ...
else
if (audioPlayer.isPlaying)
// i.e. pause the player or do other stuff
希望这对您有所帮助。
另外：请勿发布代码图片。只需在您的回复中插入代码或将其发布到 pastebin.com 之类的网站，然后在您的问题中链接该页面。这使其他人更容易回应并提出如何更改您的代码的建议。
回应您的评论： 相关的东西应该是： 在 AudioTableViewController.h：
@property (strong, nonatomic) AVAudioPlayer *audioPlayer;
在 AudioTableViewController.m 中：
@synthesize audioPlayer;
...
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
// Navigation logic may go here. Create and push another view controller.
NSUInteger row = indexPath.row;
if (row == 0)
self.audio1DetailViewController =[[Audio1DetailViewController alloc] initWithNibName:@"Audio1DetailViewController" bundle:nil];
self.audio1DetailViewController.title = @"Audio";
self.audio1DetailViewController.audioPlayer = self.audioPlayer;
[self.navigationController pushViewController:self.audio1DetailViewController animated:YES];
[self.audio1DetailViewController release];
...
Audio1DetailViewController.m
- (void)viewDidLoad
[super viewDidLoad];
NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"001Fatiha" ofType:@"MP3"]];
NSError *error;
// this is the important part: if we already have something playing, stop it!
if (audioPlayer != nil)
[audioPlayer stop];
// everything else should happen as normal.
audioPlayer = [[AVAudioPlayer alloc]
initWithContentsOfURL:url
error:&error];
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
【讨论】：
嘿@pxldlx，tnx 的答案。我试过但失败了。你说的听起来很简单，而且有道理。但我就是不明白，我想。我已经从 Audio1DetailViewController.h 在 AudioTableViewController.h 中声明了 AVAudioPlayer 然后我将整个代码（不是 viewDidLoad 部分）从 Audio1DetailViewController.m 移动到 AudioTableViewController.m 我还更改了 xib 文件中的 File'sOwner。我可以播放歌曲，但不是通过按下播放按钮，而是通过移动进度滑块。我尝试了其他一些东西，但 2 天后，我放弃了它并撤消了所有更改。 @iHilas Mh，好的。如果不查看您的代码，我真的无法为您提供太多帮助。您能否编辑您的原始问题并添加一些代码（主要是您已经发布为图像但这次作为文本发布的代码:)）。哦，还有一件事：我认为你不必改变那么多。一切都保持不变，但是您将 audioPlayer 的“所有者”更改为该超级视图（从某种意义上说，此控制器具有strong 属性）。当您遍历该新控制器时，您将参考音频播放器交给新控制器。
仍然没有成功。我已经按照你说的做了，但是它一直在同时播放 2 首歌曲，计时器和滑块也一直在自行重置。我就是想不通！【参考方案2】：
要停止同时播放 2 首歌曲，您应该这样做：
- (void)viewWillDisappear:(BOOL)animated
audioPlayer = nil;
volumeControl = nil;
如需更多关于播放音频的帮助，您可以使用苹果示例代码：
http://developer.apple.com/library/ios/#samplecode/avTouch/Introduction/Intro.html
【讨论】：
【参考方案3】：令人惊讶的是 MPMoviePlayerController 还可以播放带有控件的 MP3 播放器！！！
self.moviePlayer=[[MPMoviePlayerController alloc] initWithContentURL:url];
[self.moviePlayer.view setFrame:CGRectMake(0, 0, self.videoContainer.bounds.size.width, self.videoContainer.bounds.size.height)];
self.moviePlayer.controlStyle=MPMovieControlStyleDefault;
[self.videoContainer addSubview:self.moviePlayer.view];
[self.moviePlayer prepareToPlay];
[self.moviePlayer play];
【讨论】：
这是使用控件处理播放的正确且最直接的方法。在 iOS8 中，Apple 为您显示的控件（播放等）增加了更大的灵活性以上是关于在 iOS 中使用控件播放音频的主要内容，如果未能解决你的问题，请参考以下文章