MPNowPlayingInfoCenter播放暂停图像未更改

Question

我正在使用下面的代码。一旦应用程序在后台运行，这段代码就能完美地工作。如果应用程序不在后台运行，而我们尝试播放和暂停当前正在播放的歌曲，则播放和暂停图像不会改变。在这种case UIEventSubtypeRemoteControlPause:情况下，每次发生断点时都会出现异常。

albumArt= [[MPMediaItemArtwork alloc] initWithImage: img.image];
            NSDictionary *playingNowInfo = @{MPMediaItemPropertyTitle: (self.currentItem.songname==nil) ? (@"") : (self.currentItem.songname),
                                             MPMediaItemPropertyPlaybackDuration: @(self.currentItem.duration),
                                             MPMediaItemPropertyArtist:[MusicSetting getArtistName],
                                             MPMediaItemPropertyAlbumTitle:(self.currentItem.albumname==nil) ? (@"") : (self.currentItem.albumname),
                                             MPNowPlayingInfoPropertyPlaybackRate: @(self.player.rate),
                                             MPNowPlayingInfoPropertyElapsedPlaybackTime: @(CMTimeGetSeconds(self.player.currentItem.currentTime)),
                                             MPMediaItemPropertyArtwork:albumArt,
                                             };
            [MPNowPlayingInfoCenter defaultCenter].nowPlayingInfo = playingNowInfo;

#pragma mark - Remote Control

- (void)remoteControlReceivedWithEvent:(UIEvent *)receivedEvent {

  //  [self.manager remoteControlReceivedWithEvent:receivedEvent];
    if (receivedEvent.type == UIEventTypeRemoteControl) {

        switch (receivedEvent.subtype) {

            case UIEventSubtypeRemoteControlPlay:
                [self Onclick_Play_Pause:self];
                break;

            case UIEventSubtypeRemoteControlPause:
                [self Onclick_Play_Pause:self];
                 break;

            case UIEventSubtypeRemoteControlTogglePlayPause:

                //if ([self.manager.player isPlaying])
                if(self.manager.player.rate != 0)
                {
                    [self.manager.player pause];
                }

                else {
                    [self.manager.player play];
                }
                break;
            case UIEventSubtypeRemoteControlNextTrack:
                [self Onclick_next:self];
                NSLog(@"Next song play");
                break;
            case UIEventSubtypeRemoteControlPreviousTrack:
                [self Onclick_prev:self];
                NSLog(@"Prev song play");
                break;

            default:
                break;
        }
    }
}

- (IBAction)Onclick_Play_Pause:(id)sender {
    (AppObj).playerview_height=playviewHeight;

    if(self.manager.player.rate != 0)
    {
        [MusicSetting set_SongStatus:@"Pause"];
        [self.Play_PauseBtn setImage:[UIImage imageNamed:@"pauseImg"] forState:UIControlStateNormal];
        [self.manager pause];
    }
    else {
        [MusicSetting set_SongStatus:@"Play"];
        [MusicSetting set_isMusicPlay:@"Playing"];

        [self.Play_PauseBtn setImage:[UIImage imageNamed:@"playImg"] forState:UIControlStateNormal];

        [self.manager play];
    }
}

谢谢!

Answer 1

- (IBAction)Onclick_Play_Pause:(id)sender {
     MPNowPlayingInfoCenter *center = [MPNowPlayingInfoCenter defaultCenter];
        NSMutableDictionary *playingInfo = [NSMutableDictionary dictionaryWithDictionary:center.nowPlayingInfo];
    (AppObj).playerview_height=playviewHeight;

    if(self.manager.player.rate != 0)
    {
        [MusicSetting set_SongStatus:@"Pause"];
        [self.Play_PauseBtn setImage:[UIImage imageNamed:@"pauseImg"] forState:UIControlStateNormal];
        [self.manager pause];
         //set playback rate
        [playingInfo setObject:[NSNumber numberWithFloat:0] forKey:MPNowPlayingInfoPropertyPlaybackRate];
    }
    else 
    {
        [MusicSetting set_SongStatus:@"Play"];
        [MusicSetting set_isMusicPlay:@"Playing"];

        [self.Play_PauseBtn setImage:[UIImage imageNamed:@"playImg"] forState:UIControlStateNormal];
        [self.manager play];
        //set playback rate
        [playingInfo setObject:[NSNumber numberWithFloat:1] forKey:MPNowPlayingInfoPropertyPlaybackRate];
    }
     center.nowPlayingInfo = playingInfo;

}

Answer 2

您好，请检查是否在info.plist中添加了以下内容

​

​

Answer 3

您有以下代码

 case UIEventSubtypeRemoteControlPlay:
            [self Onclick_Play_Pause:self];
            break;

        case UIEventSubtypeRemoteControlPause:
            [self Onclick_Play_Pause:self];
             break;

        case UIEventSubtypeRemoteControlTogglePlayPause:

            //if ([self.manager.player isPlaying])
            if(self.manager.player.rate != 0)
            {
                [self.manager.player pause];
            }

            else {
                [self.manager.player play];
            }
            break;

在前两种情况下，你调用了你的方法，但在第三种情况下，你能分享你的方法的定义吗？