Question

我有两个问题。

1-我正在使用以下代码在我的iphone应用程序中添加背景音乐。

    - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        // Override point for customization after application launch.
        sleep(5);
         //this variable can be named differently

        NSString *path = [[NSBundle mainBundle] pathForResource:@"%@/background_music" ofType:@"wav"];


    // the file is stored in MyApp/SharedResources folder where as delegate is placed at MyApp/        
            backgroundSound =[[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] 

error:nil];

        backgroundSound.delegate = self;

        [backgroundSound prepareToPlay];

        [backgroundSound play];

        backgroundSound.numberOfLoops = -1;


        return YES;
    }

    @interface AppDelegate : UIResponder <UIApplicationDelegate>{
        AVAudioPlayer *backgroundSound;

    }

通过运行此代码，我的构建失败。架构i386的未定义符号：

"_OBJC_CLASS_$_AVAudioPlayer", referenced from:
      objc-class-ref in AppDelegate.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)

我的第二个问题..

假设我必须使用按钮在另一个viewController中关闭此音乐。我怎样才能做到这一点。 E.G SettingsViewController。

* thread #1: tid = 0x2c03, 0x90870c5a libSystem.dylib`__kill + 10, stop reason = signal SIGABRT
    frame #0: 0x90870c5a libSystem.dylib`__kill + 10
    frame #1: 0x90870c4c libSystem.dylib`kill$UNIX2003 + 32
    frame #2: 0x909035a5 libSystem.dylib`raise + 26
    frame #3: 0x909196e4 libSystem.dylib`abort + 93
    frame #4: 0x90895b1b libSystem.dylib`_Unwind_Resume + 59
    frame #5: 0x016c8e39 CoreFoundation`CFRunLoopRunSpecific + 345
    frame #6: 0x016c8ccb CoreFoundation`CFRunLoopRunInMode + 123
    frame #7: 0x0019e2a7 UIKit`-[UIApplication _run] + 576
    frame #8: 0x0019fa9b UIKit`UIApplicationMain + 1175
    frame #9: 0x00002a62 myApp`main + 130 at main.m:16
    frame #10: 0x000029d5 myApp`start + 53

最好的问候

Answer 1

这是链接器错误，您必须链接到AVFoundation框架。

要从其他任何类/实例/停止播放，您可以拥有多个解决方案：

一。在要停止播放的类上声明属性，并将该属性设置为原始视图控制器。然后使用属性访问该视图控制器并调用其上的方法来停止音乐。

两个。在某些中心类中，例如您的app delegate或主视图控制器，添加一个NSNotificationCenter-observer，只需在整个应用程序中使用通知，而不会弄乱属性。

在向应用添加背景音乐时构建失败

1 个答案: