iOS 设置录音权限

1.问题描述：在首次进入控制器就弹出是否允许开启麦克风的权限提示，如果选择不允许，可在下次调用时提示用户去“设置”页面进行再次开启；

2.代码

+ (BOOL)checkPermission{
    
//    AVAudioSessionRecordPermission permission = [[AVAudioSession sharedInstance] recordPermission];
//    return permission == AVAudioSessionRecordPermissionGranted;
    __block BOOL bCanRecord = YES;
    if ([[[UIDevice currentDevice]systemVersion]floatValue] >= 7.0) {
        AVAuthorizationStatus videoAuthStatus = [AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio];
         if (videoAuthStatus == AVAuthorizationStatusNotDetermined) {// 未询问用户是否授权
             AVAudioSession *audioSession = [AVAudioSession sharedInstance];
             if ([audioSession respondsToSelector:@selector(requestRecordPermission:)]) {
                 [audioSession performSelector:@selector(requestRecordPermission:) withObject:^(BOOL granted) {
                     if (granted) {
                         bCanRecord = YES;
                     } else {
                         bCanRecord = NO;
                     }
                 }];
             }
         } else if(videoAuthStatus == AVAuthorizationStatusRestricted || videoAuthStatus == AVAuthorizationStatusDenied) {
            // 未授权
            [self showSetAlertView];
        } else{
            // 已授权
            NSLog(@"已授权");
        }
    }
    return bCanRecord;
}

//提示用户进行麦克风使用授权
+ (void)showSetAlertView {
    
    [LGAlert alertWithTitle:@"麦克风权限未开启" message:@"麦克风权限未开启,请进入系统【设置】>【隐私】>【麦克风】中打开开关,开启麦克风功能" cancelTitle:@"取消" cancelBlock:^{
    } confirmTitle:@"去设置" confirmBlock:^{
        //跳入当前App设置界面
        [[UIApplication sharedApplication] openURL:[NSURL URLWithString:UIApplicationOpenSettingsURLString]];
    }];
};