iphone - 如何使用 MonoTouch 在 iPhone 上播放声音？

Question

我正在寻找类似的东西

PlaySound (uint frequency)

它存在吗？

Answer 1

来自 HowTo：http ://wiki.monotouch.net/HowTo/Sound/Play_a_Sound_or_Alert

var sound = SystemSound.FromFile (new NSUrl ("File.caf"));  
sound.PlaySystemSound (); 

Answer 2

我不知道单声道，但在 iPhone SDK 中创建和播放声音并不容易。其他替代方法是将声音作为文件提供并播放，或者创建一个表示正弦曲线的数组，并将其包装在音频包装器中，然后将其传递给许多声音 API 之一。

如果单声道被证明同样有限，则在 stackoverflow.com 中搜索 System Sound Services 和 AVAudioPlayer 作为起点。

这里有两种播放声音文件的方法：

SoundEffect.c（基于 Apple 的）

#import "SoundEffect.h"

@implementation SoundEffect
+ (id)soundEffectWithContentsOfFile:(NSString *)aPath {
    if (aPath) {
        return [[[SoundEffect alloc] initWithContentsOfFile:aPath] autorelease];
    }
    return nil;
}

- (id)initWithContentsOfFile:(NSString *)path {
    self = [super init];

    if (self != nil) {
        NSURL *aFileURL = [NSURL fileURLWithPath:path isDirectory:NO];

        if (aFileURL != nil)  {
            SystemSoundID aSoundID;
            OSStatus error = AudioServicesCreateSystemSoundID((CFURLRef)aFileURL, &aSoundID);

            if (error == kAudioServicesNoError) { // success
                _soundID = aSoundID;
            } else {
                NSLog(@"Error %d loading sound at path: %@", error, path);
                [self release], self = nil;
            }
        } else {
            NSLog(@"NSURL is nil for path: %@", path);
            [self release], self = nil;
        }
    }
    return self;
}

-(void)dealloc {
    AudioServicesDisposeSystemSoundID(_soundID);
    NSLog(@"Releasing in SoundEffect");

    [super dealloc];
//  self = nil;
}

-(void)play {
    AudioServicesPlaySystemSound(_soundID);
}

-(void)playvibe {
    AudioServicesPlayAlertSound(_soundID);
}
+(void)justvibe {
    AudioServicesPlayAlertSound(kSystemSoundID_Vibrate);
}

@end

SoundEffect.h：

#import <AudioToolbox/AudioServices.h>

@interface SoundEffect : NSObject {
    SystemSoundID _soundID;
}

+ (id)soundEffectWithContentsOfFile:(NSString *)aPath;
- (id)initWithContentsOfFile:(NSString *)path;
- (void)play;
- (void)playvibe;
+ (void)justvibe;
@end

如何使用它：

// load the sound
    gameOverSound = [[SoundEffect alloc] initWithContentsOfFile:[mainBundle pathForResource:@"buzz" ofType:@"caf"]];
// play the sound
    [gameOverSound playvibe];

当您想要以与 iPhone 的音量控制设置相同的音量播放声音并且您不需要停止或暂停声音时，这很有用。

另一种方法是：

+ (AVAudioPlayer *) newSoundWithName: (NSString *) name;
{

    NSString *soundFilePath = [[NSBundle mainBundle] pathForResource: name ofType: @"caf"];

    NSURL *fileURL = [[NSURL alloc] initFileURLWithPath: soundFilePath];

    AVAudioPlayer *newPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL: fileURL
                                                                      error: nil];
    [fileURL release];
// if the sound is large and you need to preload it:
    [newPlayer prepareToPlay];
    return (newPlayer);
}

并使用它（当您使用 AVAudioPlayer 时，您可以看到所有附加功能）：

timePassingSound = [AVAudioPlayer newSoundWithName:@"ClockTicking"];
[timePassingSound play];    
// change the volume
[timePassingSound volume:0.5];
// pause to keep it at the same place in the sound
[timePassingSound pause];    
// stop to stop completely, and go to beginning
[timePassingSound stop];    
// check to see if sound is still playing
[timePassingSound isPlaying];