耳机拔出时是否有事件发生？

在testing过程中，客户注意到拔下耳机时，iPhone中的video播放会暂停。 他想要类似的audio播放function，也许可以popup消息。

有没有人知道是否有一种事件我可以挂钩使这成为可能？

Answer 1

请参阅“audio会话编程指南”中的“ 响应路由更改 ”。

-Marc

Answer 2

这改变了iOS 7，你只需要听取名为AVAudioSessionRouteChangeNotification的通知

 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(audioRouteChanged:) name:AVAudioSessionRouteChangeNotification object:nil]; 

Answer 3

Swift 3.0 @ snakeoil的解决scheme：

  NotificationCenter.default.addObserver(self, selector: #selector(YourViewController.yourMethodThatShouldBeCalledOnChange), name: NSNotification.Name.AVAudioSessionRouteChange, object: nil) 

Answer 4

以下是我最终用来在插入耳机（和拔下耳机）时发送事件的完整实现。

我需要处理一些相当复杂的事情，以确保应用程序从后台返回后仍然可以正常工作。

CVAudioSession.h文件

 #import <Foundation/Foundation.h> #define kCVAudioInputChangedNotification @"kCVAudioInputChangedNotification" #define kCVAudioInterruptionEnded @"kCVAudioInterruptionEnded" @interface CVAudioSession : NSObject +(void) setup; +(void) destroy; +(NSString*) currentAudioRoute; +(BOOL) interrupted; @end 

CVAudioSession.m文件

 #import "CVAudioSession.h" #import <AudioToolbox/AudioToolbox.h> @implementation CVAudioSession static BOOL _isInterrupted = NO; +(void) setup { NSLog(@"CVAudioSession setup"); // Set up the audio session for recording OSStatus error = AudioSessionInitialize(NULL, NULL, interruptionListener, (__bridge void*)self); if (error) NSLog(@"ERROR INITIALIZING AUDIO SESSION! %ld\n", error); if (!error) { UInt32 category = kAudioSessionCategory_RecordAudio; // NOTE CANT PLAY BACK WITH THIS error = AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(category), &category); if (error) NSLog(@"couldn't set audio category!"); error = AudioSessionAddPropertyListener(kAudioSessionProperty_AudioRouteChange, propListener, (__bridge void*) self); if (error) NSLog(@"ERROR ADDING AUDIO SESSION PROP LISTENER! %ld\n", error); UInt32 inputAvailable = 0; UInt32 size = sizeof(inputAvailable); // we do not want to allow recording if input is not available error = AudioSessionGetProperty(kAudioSessionProperty_AudioInputAvailable, &size, &inputAvailable); if (error) NSLog(@"ERROR GETTING INPUT AVAILABILITY! %ld\n", error); // we also need to listen to see if input availability changes error = AudioSessionAddPropertyListener(kAudioSessionProperty_AudioInputAvailable, propListener, (__bridge void*) self); if (error) NSLog(@"ERROR ADDING AUDIO SESSION PROP LISTENER! %ld\n", error); error = AudioSessionSetActive(true); if (error) NSLog(@"CVAudioSession: AudioSessionSetActive (true) failed"); } } + (NSString*) currentAudioRoute { UInt32 routeSize = sizeof (CFStringRef); CFStringRef route; AudioSessionGetProperty (kAudioSessionProperty_AudioRoute, &routeSize, &route); NSString* routeStr = (__bridge NSString*)route; return routeStr; } +(void) destroy { NSLog(@"CVAudioSession destroy"); // Very important - remove the listeners, or we'll crash when audio routes etc change when we're no longer on screen OSStatus stat = AudioSessionRemovePropertyListenerWithUserData(kAudioSessionProperty_AudioRouteChange, propListener, (__bridge void*)self); NSLog(@".. AudioSessionRemovePropertyListener kAudioSessionProperty_AudioRouteChange returned %ld", stat); stat = AudioSessionRemovePropertyListenerWithUserData(kAudioSessionProperty_AudioInputAvailable, propListener, (__bridge void*)self); NSLog(@".. AudioSessionRemovePropertyListener kAudioSessionProperty_AudioInputAvailable returned %ld", stat); AudioSessionSetActive(false); // disable audio session. NSLog(@"AudioSession is now inactive"); } +(BOOL) interrupted { return _isInterrupted; } // Called when audio is interrupted for whatever reason. NOTE: doesn't always call the END one.. void interruptionListener( void * inClientData, UInt32 inInterruptionState) { if (inInterruptionState == kAudioSessionBeginInterruption) { _isInterrupted = YES; NSLog(@"CVAudioSession: interruptionListener kAudioSessionBeginInterruption. Disable audio session.."); // Try just deactivating the audiosession.. OSStatus rc = AudioSessionSetActive(false); if (rc) { NSLog(@"CVAudioSession: interruptionListener kAudioSessionBeginInterruption - AudioSessionSetActive(false) returned %.ld", rc); } else { NSLog(@"CVAudioSession: interruptionListener kAudioSessionBeginInterruption - AudioSessionSetActive(false) ok."); } } else if (inInterruptionState == kAudioSessionEndInterruption) { _isInterrupted = NO; // Reactivate the audiosession OSStatus rc = AudioSessionSetActive(true); if (rc) { NSLog(@"CVAudioSession: interruptionListener kAudioSessionEndInterruption - AudioSessionSetActive(true) returned %.ld", rc); } else { NSLog(@"CVAudioSession: interruptionListener kAudioSessionEndInterruption - AudioSessionSetActive(true) ok."); } [[NSNotificationCenter defaultCenter] postNotificationName:kCVAudioInterruptionEnded object:(__bridge NSObject*)inClientData userInfo:nil]; } } // This is called when microphone or other audio devices are plugged in and out. Is on the main thread void propListener( void * inClientData, AudioSessionPropertyID inID, UInt32 inDataSize, const void * inData) { if (inID == kAudioSessionProperty_AudioRouteChange) { CFDictionaryRef routeDictionary = (CFDictionaryRef)inData; CFNumberRef reason = (CFNumberRef)CFDictionaryGetValue(routeDictionary, CFSTR(kAudioSession_AudioRouteChangeKey_Reason)); SInt32 reasonVal; CFNumberGetValue(reason, kCFNumberSInt32Type, &reasonVal); if (reasonVal != kAudioSessionRouteChangeReason_CategoryChange) { NSLog(@"CVAudioSession: input changed"); [[NSNotificationCenter defaultCenter] postNotificationName:kCVAudioInputChangedNotification object:(__bridge NSObject*)inClientData userInfo:nil]; } } else if (inID == kAudioSessionProperty_AudioInputAvailable) { if (inDataSize == sizeof(UInt32)) { UInt32 isAvailable = *(UInt32*)inData; if (isAvailable == 0) { NSLog(@"AUDIO RECORDING IS NOT AVAILABLE"); } } } } @end