我正在制作一个应用程序,我必须使用 MPMediaPickerController 从 iPod 音乐库播放音乐。播放歌曲后,我想用一些外部声音录制歌曲(例如:- 用户的声音)。我正在尝试做同样的事情,但是遇到问题,即当应用程序首次启动时,我从 iPod 音乐库中选择一首歌曲,然后单击开始录制按钮。当我单击开始录制按钮时,我之前播放的歌曲停止但录制工作正常。录制用户的声音工作正常,但歌曲没有被录制,因为我告诉点击“开始录制”按钮时歌曲停止。我正在使用 AVAudioRecorder 进行录制。这是我正在使用的代码。
-(Void)ViewDidLoad
{
self.musicPlayer = [MPMusicPlayerController iPodMusicPlayer];
}
- (void)playOrPauseMusic:(id)sender {
MPMusicPlaybackState playbackState = self.musicPlayer.playbackState;
if (playbackState == MPMusicPlaybackStateStopped || playbackState == MPMusicPlaybackStatePaused) {
[self.musicPlayer play];
} else if (playbackState == MPMusicPlaybackStatePlaying) {
[self.musicPlayer pause];
}
}
- (void)openMediaPicker:(id)sender {
MPMediaPickerController *mediaPicker = [[MPMediaPickerController alloc] initWithMediaTypes:MPMediaTypeMusic];
mediaPicker.delegate = self;
mediaPicker.allowsPickingMultipleItems = NO; // this is the default
[mediaPicker shouldAutorotateToInterfaceOrientation:UIInterfaceOrientationLandscapeRight];
[self presentModalViewController:mediaPicker animated:YES];
}
- (void) startRecording
{
[self.musicPlayer play];
AVAudioSession *audioSession = [AVAudioSession sharedInstance];
NSError *err = nil;
[audioSession setCategory :AVAudioSessionCategoryPlayAndRecord error:&err];
if(err){
NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
return;
}
[audioSession setActive:YES error:&err];
err = nil;
if(err){
NSLog(@"audioSession: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
return;
}
recordSetting = [[NSMutableDictionary alloc] init];
// We can use kAudioFormatAppleIMA4 (4:1 compression) or kAudioFormatLinearPCM for nocompression
[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatAppleIMA4] forKey:AVFormatIDKey];
// We can use 44100, 32000, 24000, 16000 or 12000 depending on sound quality
[recordSetting setValue:[NSNumber numberWithFloat:44100.0] forKey:AVSampleRateKey];
// We can use 2(if using additional h/w) or 1 (iPhone only has one microphone)
[recordSetting setValue:[NSNumber numberWithInt: 1] forKey:AVNumberOfChannelsKey];
[recordSetting setObject:[NSNumber numberWithInt:12800] forKey:AVEncoderBitRateKey];
[recordSetting setObject:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
[recordSetting setObject:[NSNumber numberWithInt: AVAudioQualityMax] forKey: AVEncoderAudioQualityKey];
recorderFilePath = [NSString stringWithFormat:@"%@/MySound.caf", DOCUMENTS_FOLDER] ;
NSLog(@"recorderFilePath: %@",recorderFilePath);
NSURL *url = [NSURL fileURLWithPath:recorderFilePath];
err = nil;
NSData *audioData = [NSData dataWithContentsOfFile:[url path] options: 0 error:&err];
if(audioData)
{
NSFileManager *fm = [NSFileManager defaultManager];
[fm removeItemAtPath:[url path] error:&err];
}
err = nil;
recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSetting error:&err];
if(!recorder){
NSLog(@"recorder: %@ %d %@", [err domain], [err code], [[err userInfo] description]);
UIAlertView *alert =
[[UIAlertView alloc] initWithTitle: @"Warning"
message: [err localizedDescription]
delegate: nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[alert show];
return;
}
//prepare to record
[recorder setDelegate:self];
[recorder prepareToRecord];
recorder.meteringEnabled = YES;
BOOL audioHWAvailable = audioSession.inputIsAvailable;
if (! audioHWAvailable) {
UIAlertView *cantRecordAlert =
[[UIAlertView alloc] initWithTitle: @"Warning"
message: @"Audio input hardware not available"
delegate: nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[cantRecordAlert show];
return;
}
// start recording
[recorder recordForDuration:(NSTimeInterval) 2];
lblStatusMsg.text = @"Recording...";
selector:@selector(handleTimer) userInfo:nil repeats:YES];
}
这是我的 MPMusicPlayer 和 AVAudioRecorder 的代码。请帮助。在此先感谢。