我想幾個ArrayList
研究小組的音樂播放器。當前列表爲每首歌曲生成藝術家,而不僅僅是一位藝術家。這應該可以更好地解釋它:分組相同的項目在一個ArrayList - MusicPlayer
我現在對我的一個片段代碼是這樣的:
public class ArtistsFragment extends Fragment {
private ArrayList<Artist> artistList;
View view;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
view = inflater.inflate(R.layout.fragment_artists, container, false);
GridView gvArtists = (GridView) view.findViewById(R.id.gvArtists);
//instantiate list
artistList = new ArrayList<>();
//get artists from device
getArtistList();
// Group ArrayList..
artistList = new ArrayList<>(new HashSet<>(artistList));
//sort alphabetically by title
Collections.sort(artistList, new Comparator<Artist>() {
public int compare(Artist a, Artist b) {
return a.getArtist().compareTo(b.getArtist());
}
}
);
//create and set adapter
ArtistAdapter artistAdt = new ArtistAdapter(getActivity(), artistList);
gvArtists.setAdapter(artistAdt);
return view;
}
void getArtistList() {
//retrieve artist info
ContentResolver musicResolver = getActivity().getContentResolver();
Uri musicUri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
Cursor musicCursor = musicResolver.query(musicUri, null, null, null, null);
if (musicCursor != null && musicCursor.moveToFirst()) {
//get columns
int idColumn = musicCursor.getColumnIndex
(MediaStore.Audio.Media._ID);
int artistColumn = musicCursor.getColumnIndex
(MediaStore.Audio.Albums.ARTIST);
int artColumn = musicCursor.getColumnIndex
(MediaStore.Audio.Media.ARTIST_ID);
//add artists to list
do {
long thisId = musicCursor.getLong(idColumn);
String thisArtist = musicCursor.getString(artistColumn);
String thisArt = musicCursor.getString(artColumn);
artistList.add(new Artist(thisId, thisArtist, thisArt));
}
while (musicCursor.moveToNext());
musicCursor.close();
}
}
}
Artist.class
class Artist {
private final long id;
private final String artist;
private final String art;
public Artist(long artistID, String theartist, String artistArt) {
id = artistID;
artist = theartist;
art = artistArt;
}
public long getID() {
return id;
}
public String getArtist() {
return artist;
}
public String getArt() {
return art;
}
}
我已經看了Map
,我已經看了Set
,現在我只是困惑......
所以,我怎麼組我ArrayList
去除不同的藝術家的複製到那麼最終使用OnPicked
改變ArrayList
那些分組歌曲組/類別內?
我是否甚至在右邊線或者是有一個完全不同的方法來分選音樂風格/藝術家/唱片集等?
坦率地說,我沒有得到你的要求。 – Rohit5k2
你是什麼意思的分組?在你的例子中你有一個藝術家列表。你想用它做什麼?還有其他名單嗎? –
藝術家課的哪些領域讓藝術家獨特? –