最近在做录音的功能，遇到了一个问题，我使用AVAudioRecorder进行录音，参数包括对象初始化都放在了界面的viewdidload方法里，在进行录音的时候调用 recordForDuration方法， 因为我要限制最长可以录制多长时间，所以就用这个方法对录音文件及参数进行赋值， 因为我界面上有当前音频峰值的显示，所以在开始录音的时候界面效果有些变化，
我现在遇到的难题是：当点击开始录音按钮的时候， 界面效果会等到recordForDuration方法执行完才执行，执行recordForDuration这个方法又需要短暂的停顿，但又不能使用异步去做， 因为界面效果给用户的感觉就是可以录音了，
贴代码
录音工具类：
@implementation SoundUtils
-(SoundUtils *)init
{
self = [super init];
NSError *error = nil;
_recorderFilePath = [NSURL fileURLWithPath:[NSTemporaryDirectory() stringByAppendingPathComponent: [NSString stringWithFormat: @"%.0f.%@", [NSDate timeIntervalSinceReferenceDate] * 1000.0, @"caf"]]];
//录音设置
NSMutableDictionary *recordSetting = [[[NSMutableDictionary alloc] init] autorelease]; //录音格式
[recordSetting setValue :[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey: AVFormatIDKey]; //采样率
[recordSetting setValue :[NSNumber numberWithFloat:10000] forKey: AVSampleRateKey];
//通道数
[recordSetting setValue :[NSNumber numberWithInt:1] forKey: AVNumberOfChannelsKey]; //线性采样位数
[recordSetting setValue :[NSNumber numberWithInt:9] forKey: AVLinearPCMBitDepthKey];
_recorder = [[ AVAudioRecorder alloc] initWithURL:_recorderFilePath settings:recordSetting error:&error];
_recorder.delegate = self;
lowPassResults = 0;
return self;
}
-(void) recordM
{
NSError *error = nil;
AVAudioSession * audioSession = [AVAudioSession sharedInstance];
[audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error: &error];
[audioSession setActive:YES error: &error];
NSString *duration = [[NSUserDefaults standardUserDefaults] objectForKey:config_durationKey];
int recordDuration = 60;
if(duration == nil){
recordDuration = 60;
}else{
recordDuration = [duration intValue] / 1000;
}
_recorderStartTime = _recorder.currentTime;
AppLog(@"开始计时 %f",[[NSDate date] timeIntervalSince1970]);
_recorder.meteringEnabled = YES;
[_recorder recordForDuration:recordDuration];
AppLog(@"计时结束 %f",[[NSDate date] timeIntervalSince1970]);
}
界面：
- (void)viewDidLoad
{
_soundUtils = [[SoundUtils alloc] init];
}
//开始录音
-(void) recordStart
{
_progressBgImageView.alpha = 1;
if (_timer) {
[_timer invalidate];
_timer = nil;
}
_timer = [NSTimer scheduledTimerWithTimeInterval: 0.001
target: self
selector: @selector(handleTimer:)
userInfo: nil
repeats: YES];
[_soundUtils recordM];
}
- (void) handleTimer: (NSTimer *) timer
{
//峰值动画
}
