iPhone应用 AVAudioPlayer播放音频讲解

最新推荐文章于 2025-03-18 10:09:18 发布

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最新推荐文章于 2025-03-18 10:09:18 发布

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原文链接：http://www.cnblogs.com/85538649/archive/2011/12/07/2278711.html

本文深入探讨了AVAudioPlayer类在iPhone应用中的应用，提供了如何加载、播放、暂停、停止音频的方法，同时介绍了如何处理音频中断如接听电话等情况。通过实例代码演示，帮助开发者掌握音频播放的细节。

1.本文摘自：http://mobile.51cto.com/iphone-278789.htm

iPhone应用 AVAudioPlayer播放音频讲解是本文要介绍的内容，iPhone是媒体大师，其内建的iPod功能可轻松的处理音频和视频，下面我将对AVAudioPlayer这个音频播放类详细的介绍。使用AVAudioPlayer可以实现载入、播放、暂停、停止音频，监控平均和峰值音量水平.

AVAudioPlayer处理音频中断

当用户在音频回放期间受到电话时，音频会消失，出现这种情况时AVAudioPlayer委托接受audioPlayerBeginInterruption:回调，音频会话暂时无效，并且暂停播放器。

如果用户接听电话，那么应用程序中止，而应用程序委托接受一个applicationWillResignActive:回调。当通话结束，应用程序重新启动（利用applicationDidBecomeActive:回调）。如果用户拒绝接听电话那么将向委托发送audioPlayerBeginInterruption:回调。可以从此方法回复回放。

例子：

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#define COOKBOOK_PURPLE_COLOR [UIColor colorWithRed:0.20392f green:0.19607f blue:0.61176f alpha:1.0f]
#define BARBUTTON(TITLE, SELECTOR) [[[UIBarButtonItem alloc] initWithTitle:TITLE style:
UIBarButtonItemStylePlain target:self action:SELECTOR] autorelease]
#define SYSBARBUTTON(ITEM, TARGET, SELECTOR) [[[UIBarButtonItem alloc]
initWithBarButtonSystemItem:ITEM target:TARGET action:SELECTOR] autorelease]
@interface TestBedViewController : UIViewController <AVAudioPlayerDelegate>
{
AVAudioPlayer *player;
}
@property (retain) AVAudioPlayer *player;
@end
@implementation TestBedViewController
@synthesize player;
- (BOOL) prepAudio
{
NSError *error;
NSString *path = [[NSBundle mainBundle] pathForResource:@"MeetMeInSt.Louis1904" ofType:@"mp3"];
if (![[NSFileManager defaultManager] fileExistsAtPath:path]) return NO;
// Initialize the player
self.player = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:&error];
selfself.player.delegate = self;
if (!self.player)
{
NSLog(@"Error: %@", [error localizedDescription]);
return NO;
}
[self.player prepareToPlay];
return YES;
}
- (void)audioPlayerDidFinishPlaying:(AVAudioPlayer *)player successfully:(BOOL)flag
{
// just keep playing
[self.player play];
}
- (void)audioPlayerBeginInterruption:(AVAudioPlayer *)player
{
// perform any interruption handling here
printf("Interruption Detected\n");
[[NSUserDefaults standardUserDefaults] setFloat:[self.player currentTime] forKey:@"Interruption"];
}
- (void)audioPlayerEndInterruption:(AVAudioPlayer *)player
{
// resume playback at the end of the interruption
printf("Interruption ended\n");
[self.player play];
// remove the interruption key. it won't be needed
[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"Interruption"];
}
- (void) viewDidLoad
{
self.navigationController.navigationBar.tintColor = COOKBOOK_PURPLE_COLOR;
[self prepAudio];
// Check for previous interruption
if ([[NSUserDefaults standardUserDefaults] objectForKey:@"Interruption"])
{
self.player.currentTime = [[NSUserDefaults standardUserDefaults] floatForKey:@"Interruption"];
[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"Interruption"];
}
// Start playback
[self.player play];
}
@end
@interface TestBedAppDelegate : NSObject <UIApplicationDelegate>
@end
@implementation TestBedAppDelegate
- (void)applicationDidFinishLaunching:(UIApplication *)application {
UIWindow *window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:[[TestBedViewController alloc] init]];
[window addSubview:nav.view];
[window makeKeyAndVisible];
}
@end
int main(int argc, char *argv[])
{
NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
int retVal = UIApplicationMain(argc, argv, nil, @"TestBedAppDelegate");
[pool release];
return retVal;
}