同様の機能（アプリのバックグラウンドでユーザーが選択した音楽のキューを再生する）を追加できるように探しているので、xcodeでリンゴのaddMusicサンプルアプリで遊んでいます。
組み込みの MediaPicker で曲を選択した後、ユーザーが [完了] ボタンを押したときに、音楽プレーヤーが一時的に停止してから再び再生するという、この厄介なことを行います。- これは、新しい配列をキューとして適用し、現在再生中の状態を中断した場所にリセットする、apple が使用したメソッドによるものだと思います (そのように:)
// apply the new media item collection as a playback queue for the music player
[self setUserMediaItemCollection: mediaItemCollection];
[musicPlayer setQueueWithItemCollection: userMediaItemCollection];
[self setPlayedMusicOnce: YES];
[musicPlayer play];
// Obtain the music player's state so it can then be
// restored after updating the playback queue.
} else {
// Take note of whether or not the music player is playing. If it is
// it needs to be started again at the end of this method.
BOOL wasPlaying = NO;
if (musicPlayer.playbackState == MPMusicPlaybackStatePlaying) {
wasPlaying = YES;
}
// Save the now-playing item and its current playback time.
MPMediaItem *nowPlayingItem = musicPlayer.nowPlayingItem;
NSTimeInterval currentPlaybackTime = musicPlayer.currentPlaybackTime;
// Combine the previously-existing media item collection with the new one
NSMutableArray *combinedMediaItems = [[userMediaItemCollection items] mutableCopy];
NSArray *newMediaItems = [mediaItemCollection items];
[combinedMediaItems addObjectsFromArray: newMediaItems];
[self setUserMediaItemCollection: [MPMediaItemCollection collectionWithItems: (NSArray *) combinedMediaItems]];
// Apply the new media item collection as a playback queue for the music player.
[musicPlayer setQueueWithItemCollection: userMediaItemCollection];
// Restore the now-playing item and its current playback time.
musicPlayer.nowPlayingItem = nowPlayingItem;
musicPlayer.currentPlaybackTime = currentPlaybackTime;
// If the music player was playing, get it playing again.
if (wasPlaying) {
[musicPlayer play];
}
}
}
}
// If the music player was paused, leave it paused. If it was playing, it will continue to
// play on its own. The music player state is "stopped" only if the previous list of songs
// had finished or if this is the first time the user has chosen songs after app
// launch--in which case, invoke play.
- (void) restorePlaybackState {
if (musicPlayer.playbackState == MPMusicPlaybackStateStopped && userMediaItemCollection) {
if (playedMusicOnce == NO) {
[self setPlayedMusicOnce: YES];
[musicPlayer play];
}
}
}
誰でもこの問題を経験しましたか? 誰でも考えられる代替/より効率的な方法はありますか?
事前に共有していただきありがとうございます:)