我得到这个代码来判断耳机是否连接:
这在 viewDidLoad 中:
AudioSessionAddPropertyListener(kAudioSessionProperty_AudioRouteChange, audioSessionPropertyListener, nil);
这个功能:
void audioSessionPropertyListener(void* inClientData, AudioSessionPropertyID inID,
UInt32 inDataSize, const void* inData) {
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
// Determines the reason for the route change, to ensure that it is not
// because of a category change.
CFDictionaryRef routeChangeDictionary = inData;
CFNumberRef routeChangeReasonRef = CFDictionaryGetValue (routeChangeDictionary,CFSTR (kAudioSession_AudioRouteChangeKey_Reason));
SInt32 routeChangeReason;
CFNumberGetValue (routeChangeReasonRef, kCFNumberSInt32Type, &routeChangeReason);
// "Old device unavailable" indicates that a headset was unplugged, or that the
// device was removed from a dock connector that supports audio output.
if (routeChangeReason != kAudioSessionRouteChangeReason_OldDeviceUnavailable) {
[[Cubic_01AppDelegate sharedInstance] setDongleIsDisonnected];
}
if (!isHeadsetPluggedIn())
{
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);
}
else
{
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute, sizeof(audioRouteOverride), &audioRouteOverride);
}
}
这个功能:
BOOL isHeadsetPluggedIn() {
UInt32 routeSize = sizeof (CFStringRef);
CFStringRef route;
OSStatus error = AudioSessionGetProperty (kAudioSessionProperty_AudioRoute,
&routeSize,
&route
);
NSLog(@"%@", route);
BOOL isPluggedIn = !error && (route != NULL) && ([(NSString*)route rangeOfString:@"Head"].location != NSNotFound);
if (isPluggedIn) {
[[Cubic_01AppDelegate sharedInstance] setDongleIsConnected];
} else {
[[Cubic_01AppDelegate sharedInstance] setDongleIsDisonnected];
}
return (isPluggedIn);
}
谁能帮助告诉我为什么在应用程序启动之前已经连接耳机时没有调用 audioSessionPropertyListener 函数?