中介查询简化

Question

我正在尝试使用Mediastore来获取设备中的所有音乐文件。我是异步检索所有文件，但需要6-7秒才能获得所有歌曲，因此在这段时间内，用户必须看到一个行列式进度栏。

我在查询中使用了一个查询来检索每首歌的AlbumArt

有什么方法或更好的方法来处理它吗？

public ArrayList<SongList> getSongs() {
        ContentResolver musicResolver = context.getContentResolver();
        Uri musicUri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;

        Cursor musicCursor = musicResolver.query(musicUri, new String[] {MediaStore.Audio.Media.TITLE,MediaStore.Audio.Media._ID
        ,MediaStore.Audio.Media.ARTIST,MediaStore.Audio.Media.DATA,MediaStore.Audio.Media.ALBUM,MediaStore.Audio.Media.ALBUM_ID,
                MediaStore.Audio.Media.COMPOSER,MediaStore.Audio.Media.YEAR,MediaStore.Audio.Media.TRACK
        }, null, null, MediaStore.Audio.Media.TITLE);

        if (musicCursor != null && musicCursor.moveToFirst()) {
            //int value=0;
            //get columns
            int titleColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.TITLE);
            int idColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media._ID);
            int artistColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.ARTIST);
            int pathColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.DATA);
            int albumColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.ALBUM);
            int albumIDColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.ALBUM_ID);
            int composerColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.COMPOSER);
            int yearColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.YEAR);
            int trackColumn = musicCursor.getColumnIndex
                    (MediaStore.Audio.Media.TRACK);
            String thisAlbumArt = "";

            //add songs to list
            do {
                long thisId = musicCursor.getLong(idColumn);
                String thisTitle = musicCursor.getString(titleColumn);
                String thisArtist = musicCursor.getString(artistColumn);
                String thisPath = musicCursor.getString(pathColumn);
                String thisAlbum = musicCursor.getString(albumColumn);
                long thisalbumID = musicCursor.getLong(albumIDColumn);
                String thisComposer = musicCursor.getString(composerColumn);
                int thisyear = musicCursor.getInt(yearColumn);
                int track = musicCursor.getInt(trackColumn);

                songQueryList.add(thisTitle);
                Cursor cursor = musicResolver.query(MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI,
                        new String[]{MediaStore.Audio.Albums._ID, MediaStore.Audio.Albums.ALBUM_ART},
                        MediaStore.Audio.Albums._ID + "=?",
                        new String[]{musicCursor.getString(musicCursor.getColumnIndex(MediaStore.Audio.Media.ALBUM_ID))},
                        null);
                if (cursor!=null && cursor.moveToFirst()) {

                    thisAlbumArt = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.Albums.ALBUM_ART));
                    cursor.close();
                }
                if(thisPath.endsWith(".mp3")|| thisPath.endsWith(".m4p") || thisPath.endsWith(".wav") ) {

                    songs.add(new SongList(thisId, thisTitle, thisAlbum, thisArtist, thisPath, thisAlbumArt ,thisyear,track ,thisComposer ,thisalbumID));
                }
                else{

                }
                //cursor.moveToNext();
            }
            while (musicCursor.moveToNext());
        }
        if(musicCursor!=null) {
            musicCursor.close();
        }
        //Log.e("HI"," "+musicCursor.isClosed());

        /*Collections.sort(songs, new Comparator<SongList>(){
            public int compare(SongList a, SongList b){
                return a.getTitle().compareToIgnoreCase(b.getTitle());
            }
        });*/

        return songs;

    }

谢谢你在高级

Answer 1

我找到了solution.Actually，这几行代码导致了我在do-while循环中调用的延迟-

Cursor cursor = musicResolver.query(MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI,
                    new String[]{MediaStore.Audio.Albums._ID, MediaStore.Audio.Albums.ALBUM_ART},
                    MediaStore.Audio.Albums._ID + "=?",
                    new String[]{musicCursor.getString(musicCursor.getColumnIndex(MediaStore.Audio.Media.ALBUM_ID))},
                    null);

我想补充的是，查询游标是非常昂贵的，占用时间非常长，因此使用多个时间会导致延迟。

相反，我对歌曲、专辑和艺术家使用了3种不同的查询，然后使用一些逻辑将它们关联起来。

希望这能有所帮助。编码愉快。

Answer 2

这里有两个检索方法，第一个使用专辑的ID，第二个使用歌曲的ID。

// requires WRITE_EXTERNAL_STORAGE on N+
public void loadAlbumArt(int albumId, ImageView view){
    Uri artworkUri = Uri.parse("content://media/external/audio/albumart");
    Uri path = ContentUris.withAppendedId(artworkUri, albumId);
    Glide.with(view.getContext()).load(path).into(view);
}

public static void loadAlbumArt(int songId, ImageView view){
     Uri artworkUri = Uri.parse("content://media/external/audio/media/" + songId + "/albumart");
     Glide.with(view.getContext()).loadFromMediaStore(artworkUri).into(view);
}