Question

我在为Java中的简单mp3播放器创建播放列表时苦苦挣扎，但代码却无法正常工作。这是播放列表部分：

FileFilter filter = new FileNameExtensionFilter("MP3 Files", "mp3", "mpeg3");
JFileChooser chooser = new JFileChooser("C:\\Users\\Junior\\Music");
chooser.addChoosableFileFilter(filter);
chooser.setMultiSelectionEnabled(true);

int returnVal = chooser.showOpenDialog(null);

if(returnVal == JFileChooser.APPROVE_OPTION){
    //File myFile=chooser.getSelectedFile();
    File[] files=chooser.getSelectedFiles();
    //String song=myFile+"";
    for(int i=0; i<files.length;i++){
    name=files[i].getName()+"";//getting song name for display purpose
    try {
        MC.Stop();//stopping if any file is playing

        display.setText(name.substring(0,name.length()-4));//setting name songs in display (without .mp3)


        MC.Play(files[i]+"");//from main class i'm calling play method
    } catch (IOException e) {//i'm not really catching any exceptions so...

    }//end of catch
    }//end of for-loop
}//end of if

此代码正在播放所选的最后一首歌曲（即使我选择了多个文件 - 所以最后选择的歌曲也是如此），但不会进入下一首歌曲。

Answer 1

我认为这可能会帮助您阅读评论。这是我创建的播放列表。它是一个抽象类，所以你需要创建自己的类来扩展这个类，并实现loadSongs方法

public abstract class Playlist {

    public static final int LOOP_NONE = 0;
    public static final int LOOP_PLAYLIST = 1;
    public static final int LOOP_SONG = 2;

    private List<File> songs;
    private int playlistPos;
    private int loopMode;
    private boolean isShuffled;


    public Playlist() {
        isShuffled = false;
        loopMode = 0;
    }


    protected abstract List<File> loadPlaylist();


    public void initPlaylist() {
        songs = loadPlaylist();
    }


    public File getCurrentSong() {
        return songs.get(playlistPos);
    }


    public int getPlaylistPosition() {
        return playlistPos;
    }


    public void setPlaylistPosition(int playlistPos) {
        this.playlistPos = playlistPos;
    }


    public int getPlaylistSize() {
        return songs.size();
    }


    public boolean isFinalSong() {
        return playlistPos == songs.size() - 1;
    }


    public boolean isShuffled() {
        return isShuffled;
    }


    public int getLoopMode() {
        return loopMode;
    }


    public void toggleShuffle() {
        setShuffle(!isShuffled);
    }


    public void toggleLoop() {
        loopMode = (loopMode + 1) % 3;
    }


    public void skipForward() {
        playlistPos = (playlistPos + 1) % songs.size();
        // Re-shuffle songs each time the playlist loops
        if (playlistPos == 0 && isShuffled) {
            shuffle();
        }
    }


    public void skipBack() {
        playlistPos = playlistPos == 0 ? songs.size() - 1 : playlistPos - 1;
    }


    public void setLoop(int loopMode) {
        this.loopMode = loopMode;
    }


    public void setShuffle(boolean shuffle) {
        this.isShuffled = shuffle;
        if (isShuffled) {
            shuffle();
        }
        else {
            unshuffle();
        }
    }


    protected void shuffle() {
        Collections.shuffle(songs.subList(playlistPos + 1, songs.size()));
    }


    protected void unshuffle() {
        initPlaylist();
    }

}

所以你要创建一个这样的子类：

public TestPlaylist extends Playlist {

    @Override
    protected List<File> loadPlaylist() {
        // Show your file chooser, and return the selected files
        // as a list.
    }
}

要使用它，你会写：

Playlist playlist = new TestPlaylist();
playlist.initPlaylist();

// Do what you want with it, for example:
playlist.setShuffle(true);
MC.play(playlist.getCurrentSong().getAbsolutePath());

java mp3播放器中播放列表代码出错

1 个答案: