ios - 延迟背景音乐开始

Question

我正在研究一个应用程序并添加我想要的功能，但在进行过程中遇到了一些问题。

我希望有人能回答这个问题。

我想在我的应用程序中播放一些背景音乐，我已经通过在我的 AppDelegate 中使用这段代码实现了这一点

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{


    NSString* resourcePath = [[NSBundle mainBundle] resourcePath];
    resourcePath = [resourcePath stringByAppendingString:@"/smb1-1.mp3"];
    NSLog(@"Path to play: %@", resourcePath);
    NSError* err;

    //Initialize our player pointing to the path to our resource
    player = [[AVAudioPlayer alloc] initWithContentsOfURL:
              [NSURL fileURLWithPath:resourcePath] error:&err];

    if( err ){
        //bail!
        NSLog(@"Failed with reason: %@", [err localizedDescription]);
    }
    else{
        //set our delegate and begin playback
        player.delegate = self;
        [player play];
        player.numberOfLoops = -1;
        player.currentTime = 0;
        player.volume = 0.5;

    }

    // Override point for customization after application launch.
    return YES;
}

所以一切都很好。但是，我希望音频在应用程序完成启动后 3 秒开始播放，而不是立即开始播放。

有谁知道我如何对此设置延迟或解释不同的方式。我不会在每次音乐修复之前都有延迟，只是为了第一次启动。

提前致谢。

Answer 1

希望对您有所帮助:

1. 在您的 appDelegate 中创建一个 BOOL iVar:

   @implementation aaaAppDelegate        
   {
       BOOL firstTime;
   }
   

2. 将此添加到您的 didFinishLaunchingWithOptions 方法中:

   - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
   {
       // Override point for customization after application launch.
       firstTime = YES;
       return YES;
   }
   

3. 将此添加到 appDelegate 中的 applicationDidBecomeActive 方法。

       - (void)applicationDidBecomeActive:(UIApplication *)application
       {
           if (firstTime)
           {
               firstTime = NO;
               [self performSelector:@selector(playMusic) withObject:nil afterDelay:3.0];
           }
       }
   

4. 将您的音乐播放代码从 ​​didFinishLaunchingWithOptions 移至名为 playMusic 的单独方法:

    -(void)playMusic
    {
        NSString* resourcePath = [[NSBundle mainBundle] resourcePath];
        resourcePath = [resourcePath stringByAppendingString:@"/smb1-1.mp3"];
        NSLog(@"Path to play: %@", resourcePath);
        NSError* err;
   
        //Initialize our player pointing to the path to our resource
        player = [[AVAudioPlayer alloc] initWithContentsOfURL:
        [NSURL fileURLWithPath:resourcePath] error:&err];
   
        if( err ){
            //bail!
            NSLog(@"Failed with reason: %@", [err localizedDescription]);
        }
        else{
            //set our delegate and begin playback
            player.delegate = self;
            [player play];
            player.numberOfLoops = -1;
            player.currentTime = 0;
            player.volume = 0.5;
   
        }
    }