我使用了这些代码
- (void)viewDidLoad
{
[[AVAudioSession sharedInstance] setDelegate: self];
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryAmbient error: nil];
AudioSessionAddPropertyListener (
kAudioSessionProperty_AudioRouteChange,
audioRouteChangeListenerCallback,
self
);
NSError *activationError = nil;
[[AVAudioSession sharedInstance] setActive: YES error: &activationError];
}
和
void audioRouteChangeListenerCallback (void *inUserData, AudioSessionPropertyID inPropertyID, UInt32 inPropertyValueSize, const void *inPropertyValue ) {
// ensure that this callback was invoked for a route change
if (inPropertyID != kAudioSessionProperty_AudioRouteChange) return;
{
// Determines the reason for the route change, to ensure that it is not
// because of a category change.
CFDictionaryRef routeChangeDictionary = (CFDictionaryRef)inPropertyValue;
CFNumberRef routeChangeReasonRef = (CFNumberRef)CFDictionaryGetValue (routeChangeDictionary, CFSTR (kAudioSession_AudioRouteChangeKey_Reason) );
SInt32 routeChangeReason;
CFNumberGetValue (routeChangeReasonRef, kCFNumberSInt32Type, &routeChangeReason);
if (routeChangeReason == kAudioSessionRouteChangeReason_OldDeviceUnavailable) {
//Handle Headset Unplugged
} else if (routeChangeReason == kAudioSessionRouteChangeReason_NewDeviceAvailable) {
//Handle Headset plugged in
}
}
}
检测我的项目中是否插入或拔出音频插孔，但最终出现此错误
Undefined symbols for architecture armv7:
"_AVAudioSessionCategoryAmbient", referenced from:
-[ViewController viewDidLoad] in ViewController.o
"_OBJC_CLASS_$_AVAudioSession", referenced from:
objc-class-ref in ViewController.o
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)
那么其中的问题是什么？我是 ios 的初学者，任何帮助将不胜感激。