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Java 按字母顺序排列音乐播放器的播放列表(Android Studio)_Java_Android_Sorting_Alphabetical_Android Music Player - Fatal编程技术网

Java 按字母顺序排列音乐播放器的播放列表(Android Studio)

Java 按字母顺序排列音乐播放器的播放列表(Android Studio),java,android,sorting,alphabetical,android-music-player,Java,Android,Sorting,Alphabetical,Android Music Player,我下载了这个项目: 我会按字母顺序排列“所有歌曲”部分的歌曲。我试着把它放在onCreate中: Collections.sort(songList, Comparator.comparing((Function<? super Object, ? extends Comparable>) songList)); 应提供in作为方法参考: Collections.sort(songList,Comparator.comparing(songList::getTitle)); 这是

我下载了这个项目:

我会按字母顺序排列“所有歌曲”部分的歌曲。我试着把它放在onCreate中:

Collections.sort(songList, Comparator.comparing((Function<? super Object, ? extends Comparable>) songList));
应提供in作为方法参考:

Collections.sort(songList,Comparator.comparing(songList::getTitle));

这是否回答了您的问题?不,我的ArrayList没有对象。它没有任何你想排序的对象?问题是我不太理解整个代码…如果有人能向我解释,我将不胜感激…你能给我看一下类歌曲列表吗?
public class MainActivity extends AppCompatActivity implements View.OnClickListener, AllSongFragment.createDataParse, FavSongFragment.createDataParsed, CurrentSongFragment.createDataParsed {

    private Menu menu;

    private ImageButton imgBtnPlayPause, imgbtnReplay, imgBtnPrev, imgBtnNext, imgBtnSetting;
    private TabLayout tabLayout;
    private ViewPager viewPager;
    private SeekBar seekbarController;
    private DrawerLayout mDrawerLayout;
    private TextView tvCurrentTime, tvTotalTime;


    private ArrayList<SongsList> songList;
    private int currentPosition;
    private String searchText = "";
    private SongsList currSong;

    private boolean checkFlag = false, repeatFlag = false, playContinueFlag = false, favFlag = true, playlistFlag = false;
    private final int MY_PERMISSION_REQUEST = 100;
    private int allSongLength;
    MediaPlayer mediaPlayer;
    Handler handler;
    Runnable runnable;

    @RequiresApi(api = Build.VERSION_CODES.N)
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        init();
        grantedPermission();
        onPrepared();
        //Sorting playlist here
        Collections.sort(songList, Comparator.comparing((Function<? super Object, ? extends Comparable>) songList));

    }
package com.example.soc_macmini_15.musicplayer.Model;
public class SongsList {

    private String title;
    private String subTitle;
    private String path;

    public String getPath() {
        return path;
    }

    public void setPath(String path) {
        this.path = path;
    }

    public SongsList(String title, String subTitle, String path) {
        this.title = title;
        this.subTitle = subTitle;
        this.path = path;

    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getSubTitle() {
        return subTitle;
    }

}