ios - 如何在锁定屏幕上添加快退按钮？

Question

我已经AVPlayer通过MPNowPlayingInfoCenter. 但我找不到如何像标准音乐应用程序那样添加 ±15 秒倒带按钮。所以问题是如何在锁定屏幕上添加这个按钮？

Answer 1

我现在正在使用AVAudioPlayer，但- (void)remoteControlReceivedWithEvent:(UIEvent *)event不能与您使用的播放器类型有关。

按照这个：

在视图控制器的viewDidLoad方法中添加以下代码：

//Make sure the system follows our playback status - to support the playback when the app enters the background mode.
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];

然后添加这些方法： viewDidAppear:：（如果尚未实现）

- (void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    //Once the view has loaded then we can register to begin recieving controls and we can become the first responder
    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
    [self becomeFirstResponder];
}

viewWillDisappear:（如果尚未实施）

- (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];

    //End recieving events
    [[UIApplication sharedApplication] endReceivingRemoteControlEvents];
    [self resignFirstResponder];
}

和：

//Make sure we can recieve remote control events
- (BOOL)canBecomeFirstResponder {
    return YES;
}

- (void)remoteControlReceivedWithEvent:(UIEvent *)event {
    //if it is a remote control event handle it correctly
    if (event.type == UIEventTypeRemoteControl)
    {
        if (event.subtype == UIEventSubtypeRemoteControlPlay)
        {
            [self playAudio];
        }
        else if (event.subtype == UIEventSubtypeRemoteControlPause)
        {
            [self pauseAudio];
        }
        else if (event.subtype == UIEventSubtypeRemoteControlTogglePlayPause)
        {
            [self togglePlayPause];
        }

        else if (event.subtype == UIEventSubtypeRemoteControlBeginSeekingBackward)
        {
            [self rewindTheAudio]; //You must implement 15" rewinding in this method.
        }
        else if (event.subtype == UIEventSubtypeRemoteControlBeginSeekingForward)
        {
            [self fastForwardTheAudio]; //You must implement 15" fast-forwarding in this method.
        }

    }
}

这在我的应用程序中运行良好，但是如果您希望能够在所有视图控制器中接收远程控制事件，那么您应该在AppDelegate.