ios - NSObject 类标签的连续更新值

Question

我的歌曲正在从辅助类(派生自 NSObject)播放，我想更新 View 中的 UI，我知道一种方法 PostNotification。还有其他解决方案吗？

+(void)playRemoteFile:(NSString*)songURL {

    [[AFSoundManager sharedManager] startStreamingRemoteAudioFromURL:songURL andBlock:^(int percentage, CGFloat elapsedTime, CGFloat timeRemaining, NSError *error, BOOL finished) {

        if (!error) {
            // I want to update GUI here
            //_slider.value = percentage * 0.01;                
        } 
    }];
}

Answer 1

如果您从 viewController 调用 playRemoteFile 并且可以修改 playRemoteFile 方法。如何将其更改为:

+ (void)playRemoteFile:(NSString*)songURL andBlock:(void (^)(int percentage, CGFloat elapsedTime, CGFloat timeRemaining, NSError *error, BOOL finished))block {
    [[AFSoundManager sharedManager] startStreamingRemoteAudioFromURL:songURL andBlock:^(int percentage, CGFloat elapsedTime, CGFloat timeRemaining, NSError *error, BOOL finished) {
        block(percentage, elapsedTime, timeRemaining, error, finished)
    }];
}

然后在 viewController 中执行此操作

[someObject playRemoteFile: songURL andBlock:^(int percentage, CGFloat elapsedTime, CGFloat timeRemaining, NSError *error, BOOL finished){
    if (!error) {
        // update GUI here
        //_slider.value = percentage * 0.01;                
    } 
}]