Objective C 中 AudioToolbox 的引用错误

我在一个简单的 Roulett 应用程序中尝试播放一些 wav 文件时遇到以下错误。我不确定该错误意味着什么，因为代码中没有出现警告标志，并且我已导入

这是错误：

未定义的符号：
“_AudioServicesCreateSystemSoundID”， 参考自： -[CustomPickerViewController playWinSound] 中 CustomPickerViewController.o -CustomPickerViewController.o 中的[CustomPickerViewController spin:] “_AudioServicesPlaySystemSound”， 参考自： -[CustomPickerViewController playWinSound] 中 CustomPickerViewController.o -CustomPickerViewController.o 中的[CustomPickerViewController spin:] ld：未找到符号collect2：ld 返回 1 退出状态
“_AudioServicesCreateSystemSoundID”， 参考自： -[CustomPickerViewController playWinSound] 中 CustomPickerViewController.o -CustomPickerViewController.o 中的[CustomPickerViewController spin:] “_AudioServicesPlaySystemSound”， 参考自： -[CustomPickerViewController playWinSound] 中 CustomPickerViewController.o -CustomPickerViewController.o 中的[CustomPickerViewController spin:] ld：未找到符号collect2：ld 返回 1 退出状态

这是代码：

#import "CustomPickerViewController.h"
#import <AudioToolbox/AudioToolbox.h>

@implementation CustomPickerViewController
@synthesize picker;
@synthesize winLabel;
@synthesize column1;
@synthesize column2;
@synthesize column3;
@synthesize column4;
@synthesize column5;
@synthesize button;

- (void)showButton
{
    button.hidden = NO;
}

-(void)playWinSound
{
    NSString *path = [[NSBundle mainBundle] pathForResource:@"win" ofType:@"wav"];
    SystemSoundID soundID;
    AudioServicesCreateSystemSoundID((CFURLRef)[NSURL fileURLWithPath:path], &soundID);
    AudioServicesPlaySystemSound (soundID);     
    winLabel.text = @"WIN!";
    [self performSelector:@selector(showButton) withObject:nil afterDelay:1.5];
}



-(IBAction)spin:(id)sender
{
    BOOL win = NO;
    int numInRow = 1;
    int lastVal = -1;
    for (int i = 0; i < 5; i++)
    {
        int newValue =random() % [self.column1 count];

        if (newValue == lastVal)
            numInRow++;
        else
            numInRow = 1;

        lastVal = newValue;
        [picker selectRow:newValue inComponent:i animated: YES];
        [picker reloadComponent:i];
        if (numInRow >= 3)
            win = YES;
    }

    button.hidden = YES;
    NSString *path = [[NSBundle mainBundle] pathForResource:@"crunch"ofType:@"wav"];
    SystemSoundID soundID;
    AudioServicesCreateSystemSoundID((CFURLRef) [NSURL fileURLWithPath:path], &soundID);
    AudioServicesPlaySystemSound(soundID);

    if (win)
        [self performSelector:@selector(playWinSound) withObject: nil afterDelay: .5];
    else 
        [self performSelector:@selector(showButton) withObject: nil afterDelay: .5];

    winLabel.text = @"";
}

找到了。意识到我没有在 XCode 中导入 Framework AudioToolbox.Framework。 :)