Question

我正在尝试根据使用AVAudioPlayer按下哪个按钮播放声音。 （这不是音板或放屁应用程序。）

我已在头文件中使用此代码链接所有按钮：

@interface appViewController : UIViewController <AVAudioPlayerDelegate> {

AVAudioPlayer *player;

UIButton *C4;
UIButton *Bb4;
UIButton *B4;
UIButton *A4;
UIButton *Ab4;
UIButton *As4;
UIButton *G3;
UIButton *Gb3;
UIButton *Gs3;
UIButton *F3;
UIButton *Fs3;
UIButton *E3;
UIButton *Eb3;
UIButton *D3;
UIButton *Db3;
UIButton *Ds3;
UIButton *C3;
UIButton *Cs3;
}

@property (nonatomic, retain) AVAudioPlayer *player;

@property (nonatomic, retain) IBOutlet UIButton *C4;
@property (nonatomic, retain) IBOutlet UIButton *B4;
@property (nonatomic, retain) IBOutlet UIButton *Bb4;
@property (nonatomic, retain) IBOutlet UIButton *A4;
@property (nonatomic, retain) IBOutlet UIButton *Ab4;
@property (nonatomic, retain) IBOutlet UIButton *As4;
@property (nonatomic, retain) IBOutlet UIButton *G3;
@property (nonatomic, retain) IBOutlet UIButton *Gb3;
@property (nonatomic, retain) IBOutlet UIButton *Gs3;
@property (nonatomic, retain) IBOutlet UIButton *F3;
@property (nonatomic, retain) IBOutlet UIButton *Fs3;
@property (nonatomic, retain) IBOutlet UIButton *E3;
@property (nonatomic, retain) IBOutlet UIButton *Eb3;
@property (nonatomic, retain) IBOutlet UIButton *D3;
@property (nonatomic, retain) IBOutlet UIButton *Db3;
@property (nonatomic, retain) IBOutlet UIButton *Ds3;
@property (nonatomic, retain) IBOutlet UIButton *C3;
@property (nonatomic, retain) IBOutlet UIButton *Cs3;

- (IBAction) playNote;

@end

按钮全部链接到interfaceBuilder中的事件“playNote”，并且每个音符都根据音符名称链接到正确的引用插座。

所有* .mp3声音文件都以UIButton名称命名（IE-C3 == C3.mp3）。

在我的实现文件中，我按下C3按钮时只有一个音符：

#import "sonicfitViewController.h"

@implementation appViewController
@synthesize C3, Cs3, D3, Ds3, Db3, E3, Eb3, F3, Fs3, G3, Gs3, A4, Ab4, As4, B4, Bb4, C4;

// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {

    NSString *path = [[NSBundle mainBundle] pathForResource:@"3C" ofType:@"mp3"];
    NSLog(@"path: %@", path);
    NSURL *file = [[NSURL alloc] initFileURLWithPath:path];

    AVAudioPlayer *p = [[AVAudioPlayer alloc]
                        initWithContentsOfURL:file error:nil];
    [file release];

    self.player = p;
    [p release];

    [player prepareToPlay];
    [player setDelegate:self];

    [super viewDidLoad];
}

- (IBAction) playNote {
    [self.player play];
}

现在，有了上述内容，我有两个问题：

首先，NSLog报告NULL并在尝试播放文件时崩溃。我已经将mp3添加到资源文件夹中，它们已被复制而不仅仅是链接。它们不在资源文件夹下的子文件夹中。
其次，如何设置它以便当按下按钮C3时，它会播放C3.mp3并且F3播放F3.mp3而不为每个不同的按钮写入重复的代码行？ playNote应该像

NSString * path = [[NSBundle mainBundle] pathForResource：nameOfButton ofType：@“mp3”];

而不是专门定义它（@“C3”）。

有没有更好的方法来执行此操作以及为什么*路径报告NULL并在加载应用时崩溃？

我很确定这就像添加额外的变量输入一样简单 - （IBAction）playNote：buttonName并将所有代码放在playNote函数中调用AVAudioPlayer，但我不确定代码是这样做的。< / p>

Answer 1

使用相同的选择器执行多个操作是一项常见任务。只需为每个按钮设置一个标签属性，并使用NSStrings的NSArray来存储文件名。您甚至无需单独创建每个按钮。有关类似问题problem with selector in iphone?的答案，请参阅代码示例。

检查您的文件是否真的被复制到bundle。例如在模拟器中使用NSLog记录您的bundle目录（@“myBundle：％@”，[[NSBundle mainBundle] bundlePath]）; 并查看文件。

根据iPhone / xcode上按下的按钮播放声音

1 个答案: