iOS 声音按键监听和实现

首先包含这两个头文件以及加入对应的框架

#import <MediaPlayer/MediaPlayer.h>

#import <AudioToolbox/AudioToolbox.h>

添加声音通知的监听

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(volumeChanged:) name:@"AVSystemController_SystemVolumeDidChangeNotification" object:nil];

// 获取当前系统音量

self.volume = [[MPMusicPlayerController applicationMusicPlayer] volume];

// 判断是否静音

- (BOOL) isMuted

{

CFStringRef route;

UInt32 routeSize = sizeof(CFStringRef);

OSStatus status = AudioSessionGetProperty(kAudioSessionProperty_AudioRoute, &routeSize, &route);

if (status == kAudioSessionNoError)

{

if (route == NULL || !CFStringGetLength(route))

return TRUE;

}

return FALSE;

}

// 声音通知监听的实现

- (void) volumeChanged:(NSNotification *) notification

{

// 获取当前声音的值

float volume =

[[[notification userInfo]

objectForKey:@"AVSystemController_AudioVolumeNotificationParameter"]

floatValue];

//    NSLog(@"现在音量：%f",volume);

if (!self.isMuted && volume < self.volume && self.acceptBtn.hidden == NO) {

// 设置音量为静音

[[MPMusicPlayerController applicationMusicPlayer] setVolume:0.0];

// 添加系统震动

AudioServicesRemoveSystemSoundCompletion(kSystemSoundID_Vibrate);

NSLog(@"----isMuted音量:%f-------",volume);

} else if (volume > self.volume && self.acceptBtn.hidden == NO){

[[MPMusicPlayerController applicationMusicPlayer] setVolume:volume];

NSLog(@"----!isMuted音量:%f-------",volume);

}

// 更新记录音量值的变量

self.volume = volume;

}