objective-c - 将 NSString 与 AVAudioPlayer 一起使用

Question

我在使用 AVAudioPlayer 时遇到问题，无法从其他 View 获取声音。它可以与 AudioToolbox 完美配合，但不能与 AVAudioPlayer 配合使用。这是我的代码:

.h 文件:

#import <UIKit/UIKit.h>
#import <AudioToolbox/AudioToolbox.h>
#import <AVFoundation/AVFoundation.h>
#import <CoreText/CoreText.h>
#import "SimpleTableCelldetail.h"

int clicked;


@interface DetailViewController : UIViewController {

AVAudioPlayer *audioPlayer;
IBOutlet UIButton *start;

}

@property (strong, nonatomic) IBOutlet NSString *audioSon;

@end

.m文件

-(IBAction)play:(id)sender {

if(clicked == 0) {
    clicked = 1;
    NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:audioSon, [[NSBundle mainBundle] resourcePath]]];

    NSError *error;
    audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
    audioPlayer.numberOfLoops = 0;

    [audioPlayer play];
    [start setTitle:@"Stop" forState:UIControlStateNormal];
}
else {
    clicked = 0;
    [audioPlayer stop];
    [start setTitle:@"Ecouter" forState:UIControlStateNormal];
}
}

当我运行此代码时，按钮不播放任何声音。audioSon 的值为“sound01.m4r”。

当我更换线路时

NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:audioSon, [[NSBundle mainBundle] resourcePath]]];

与

NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/sound01.m4r", [[NSBundle mainBundle] resourcePath]]];

它有效，但 xcode 显示错误:

2012-08-01 01:59:44.697 CustomTable[12709:3703] Error loading /System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn:  dlopen(/System/Library/Extensions/AppleHDA.kext/Contents/PlugIns/AppleHDAHALPlugIn.bundle/Contents/MacOS/AppleHDAHALPlugIn, 262): Symbol not found: ___CFObjCIsCollectable
  Referenced from: /System/Library/Frameworks/Security.framework/Versions/A/Security
  Expected in: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.1.sdk/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation
 in /System/Library/Frameworks/Security.framework/Versions/A/Security

有什么想法吗？

谢谢。

Answer 1

当您应该使用 stringByAppendingPathComponent 时，您在原始行中使用了 stringWithFormat。如果您更改此设置，您将访问正确的文件并且您的程序应该可以运行。

NSURL *url = [NSURL fileURLWithPath:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:audioSon];