如何显示ipodLibrary中从ipableLibrary中播放的ipodLibrary中的选定歌曲 [英] how to display selected songs from ipodLibrary played from avplayer in uitableview

问题描述

我正在使用AVPlayer播放歌曲.我也可以在后台播放它.有一个名为showPlaylist的UIButton.当我点击它时，我需要显示从UITableView中的ipodLibrary中选择的歌曲列表，并且我应该能够显示插图，歌曲中剩余的分钟数和艺术家的名字(如果在列表中可用).歌曲.

I am playing songs by using AVPlayer. I am able to play it in background as well. There is a UIButton called showPlaylist. When I tap on it I need to display list of songs which I have selected from ipodLibrary in UITableView and I should be able to display artwork, number of mins remaining in the song and the artist's name if it is available in the song.

我有播放和暂停按钮:当我单击暂停按钮时，歌曲会暂停，但是当我再次点击播放按钮时，它会转到ipodLibrary.当我点击播放"按钮时如何恢复播放?

I have play and pause buttons: when I click the pause button, the song is paused but when I tap on the play button again, it goes to the ipodLibrary. How to resume play when I tap on the play button?

并且当该UITableView中有多首歌曲时，我希望它在第一首曲目完成后立即继续到下一首曲目.我想知道如何做到这一点.

And when there are multiple songs in that UITableView, I want it to continue to the next track as soon as the first track completes. I was wondering how to do that.

-(IBAction)playButtonPressed:(UIButton *)sender {
  // Create picker view
  MPMediaPickerController* picker = [[MPMediaPickerController alloc] init];
  picker.delegate = self;
  if (userMediaItemCollection) {
    MusicTableViewController *controller = [[MusicTableViewController alloc]
     initWithNibName: @"MusicTableView" bundle: nil];
    controller.delegate = self;
    controller.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    [self presentModalViewController: controller animated: YES];
  } else {
    MPMediaPickerController *picker = [[MPMediaPickerController alloc]
      initWithMediaTypes: MPMediaTypeMusic];
    picker.delegate  = self;
    picker.allowsPickingMultipleItems = YES;
    picker.prompt = NSLocalizedString
      (@"Add songs to play", "Prompt in media item picker");
    [[UIApplication sharedApplication] setStatusBarStyle:
      UIStatusBarStyleDefault animated: YES];
    [self presentModalViewController: picker animated: YES];
  }
}

-(IBAction)pauseButtonPressed:(UIButton *)sender {
  [myPlayer pause];
}

-(void) mediaPickerDidCancel:(MPMediaPickerController *)mediaPicker {
  [self dismissViewControllerAnimated:YES completion:nil];
}

-(void) mediaPicker:(MPMediaPickerController *)mediaPicker didPickMediaItems:
  (MPMediaItemCollection *)mediaItemCollection {
  [self dismissViewControllerAnimated:YES completion:nil];
  NSURL* assetUrl = [mediaItemCollection.representativeItem
    valueForProperty:MPMediaItemPropertyAssetURL];
  AVURLAsset* asset = [AVURLAsset URLAssetWithURL:assetUrl options:nil];
  AVPlayerItem* playerItem = [AVPlayerItem playerItemWithAsset:asset];
  myPlayer = [AVPlayer playerWithPlayerItem:playerItem];
  [myPlayer play];
}

- (void)viewDidAppear:(BOOL)animated {
  [super viewDidAppear:animated];
  [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
  [self becomeFirstResponder];
}

- (BOOL)canBecomeFirstResponder {
  return YES;
}

- (void)viewWillDisappear:(BOOL)animated {
  [super viewWillDisappear:animated];
  [[UIApplication sharedApplication] endReceivingRemoteControlEvents];
  [self resignFirstResponder];
}

-(void)remoteControlReceivedWithEvent:(UIEvent *)event {
  switch (event.subtype) {
    case UIEventSubtypeRemoteControlTogglePlayPause:
      if (myPlayer.rate == 0.0) {
        [myPlayer play];
      } else {
        [myPlayer pause];
      }
      break;
    case UIEventSubtypeRemoteControlPlay:
      [myPlayer play];
      break;
    case UIEventSubtypeRemoteControlPause:
      [myPlayer pause];
      break;
    default:
      break;
  }
}

推荐答案

我将研究Apple的示例代码清楚地演示了如何完成您描述的所有操作.

I would look into Apple's sample code "Add Music" which clearly demonstrated how to do everything you've described.

此示例应用程序将用从iPod库中保存到MPMediaItemCollection中的选定歌曲的可变副本的内容填充UITableView的内容来全面介绍您.它还显示了如何使用MPMediaItems和MPMediaItemCollections将特定于曲目的属性显示为单元格标题标签等.

This sample application runs you through the ins and outs of populating a UITableView with the contents of a mutable copy of selected songs from the iPod library saved into a MPMediaItemCollection. It also shows how using MPMediaItems and MPMediaItemCollections you can display track specific attributes as the cells title label, etc.

1. 要填充表格视图，您可以将其设置如下:

1. For populating the table view, you could set it up something like this:

MPMediaItem *mediaItem = (MPMediaItem *)[collectionMutableCopy objectAtIndex:row];

MPMediaItemArtwork *artwork = [mediaItem valueForProperty:MPMediaItemPropertyArtwork];

if (mediaItem) {
    cell.textLabel.text = [mediaItem valueForProperty:MPMediaItemPropertyTitle];
    cell.detailTextLabel.text = [mediaItem valueForProperty:MPMediaItemPropertyArtist];
    if (artwork != nil) {
        cell.imageView.image = [artwork imageWithSize:CGSizeMake (40, 40)];
    }else{
        cell.imageView.image = [UIImage imageNamed:@"no_artwork.png"];
    }
}

将链接到播放按钮的按钮重命名为选择音乐"，并创建一个名为播放"的新按钮，并将其操作设置为:

Rename the button linked to the play button as "Select Music" and make a new button called "Play" with its action set to:

- (IBAction)playMusic { [myPlayer play]; }

- (IBAction)playMusic { [myPlayer play]; }

编辑:根据MPMediaItemCollection的内容创建数组:

Creating array from contents of MPMediaItemCollection:

NSMutableArray *collectionMutableCopy = [[NSMutableArray alloc] initWithArray:myMediaItemCollection.items];

在项目中取消注释以下行:

EDIT 2: Uncomment the following lines in the project:

在- (void) registerForMediaPlayerNotifications

/*
 // This sample doesn't use libray change notifications; this code is here to show how
 //     it's done if you need it.
 [[NSNotificationCenter defaultCenter] removeObserver: self
 name: MPMediaLibraryDidChangeNotification
 object: musicPlayer];

 [[MPMediaLibrary defaultMediaLibrary] endGeneratingLibraryChangeNotifications];

 */

在- (void)dealloc

/*
 // This sample doesn't use libray change notifications; this code is here to show how
 //     it's done if you need it.
 [notificationCenter addObserver: self
 selector: @selector (handle_iPodLibraryChanged:)
 name: MPMediaLibraryDidChangeNotification
 object: musicPlayer];

 [[MPMediaLibrary defaultMediaLibrary] beginGeneratingLibraryChangeNotifications];
 */

替换此行:

[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryAmbient error: nil];

有了这个

 [[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error: nil];

 UInt32 doSetProperty = 0;
 AudioSessionSetProperty (
 kAudioSessionProperty_OverrideCategoryMixWithOthers,
 sizeof (doSetProperty),
 &doSetProperty
 );

然后将以下内容添加到项目的info.plist文件中

Then add the following to your projects info.plist file

这篇关于如何显示ipodLibrary中从ipableLibrary中播放的ipodLibrary中的选定歌曲的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！