Question

在我正在编写的应用程序中，用户可以从数据库中选择一个条目并播放该条目的内容：条目由多个声音文件组成（没有限制）。在我的应用程序中，我将一个条目（已存储在我的数据库中）的声音文件的URI位置返回到List中。代码如下：

public void audioPlayer() {
    // set up MediaPlayer
    MediaPlayer mp = new MediaPlayer();
    DatabaseHandler db = new DatabaseHandler(this);
    Entry retrieveEntry = new Entry();

    retrieveEntry = db.getEntry();

    List<String> path = retrieveEntry.getAudioUri();

    path.size();

    System.out.println("PATH SIZE: " +path.size());

    System.out.println("FILEZ: " + path);

    Iterator<String> i = path.iterator();
    String myAudio;
    int count = 0;

    while (i.hasNext()) {
        System.out.println(count);
            myAudio = i.next();
            System.out.println("MY AUDIO: " + myAudio);

            MediaPlayer player = MediaPlayer.create(this, Uri.parse(myAudio));
            player.start();
            player.stop();
            player = MediaPlayer.create(this, Uri.parse(myAudio));
            player.start();

            count++;
        }
}

我的用户要求有用户输入播放文件 - 有没有办法播放第一个文件，然后等待用户按下按钮，然后播放第二个文件，然后等待用户按下按钮等？此时，按下播放按钮时，所有已返回的声音文件将同时播放，而不是一个接一个播放。

提前感谢您提供的任何帮助！

Answer 1

您可以使用此课程播放播放列表。这将启动一个音频，当音频结束时，它将开始播放下一个音频，直到列表结束。如果你想在循环中播放播放列表，即在到达结束后开始播放第一个音频，那么在startPlayingPlaylist(list,looping)

中传递isLooping = true

    AudioPlayer player = new AudioPlayer();
    player.startPlayingPlaylist(list, false);

类

public class AudioPlayer{
    MediaPlayer player = null;
    ArrayList<String> playlist = null;
    int position = 0;

    public AudioPlayer() {
        super();
        // TODO Auto-generated constructor stub
    }
    public void startPlayingPlaylist(ArrayList<String> list, boolean looping){
        playlist = list;
        if(player!=null){
            player.release();
        }
        if(playlist!=null && playlist.size()>0){
            player = MediaPlayer.create(LMApplicaton.getInstance(),Uri.parse(playlist.get(position)));
            player.setWakeMode(LMApplicaton.getInstance(), PowerManager.PARTIAL_WAKE_LOCK);
            player.setLooping(looping);
            player.start();
            // Set onCompletion listener
            player.setOnCompletionListener(new OnCompletionListener() {

                @Override
                public void onCompletion(MediaPlayer mp) {
                    position = position+1;
                    if(position<playlist.size()){
                        try {
                            player.reset();
                            player.setDataSource(playlist.get(position));
                            player.prepareAsync();
                        } catch (IllegalArgumentException e) {
                            e.printStackTrace();
                        } catch (IllegalStateException e) {
                            e.printStackTrace();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }

                    } else if(player.isLooping()==true){
                        position = position%playlist.size();
                        try {
                            player.reset();
                            player.setDataSource(playlist.get(position));
                            player.prepareAsync();
                        } catch (IllegalArgumentException e) {
                            e.printStackTrace();
                        } catch (IllegalStateException e) {
                            e.printStackTrace();
                        } catch (IOException e) {
                            e.printStackTrace();
                        }
                    }
                    else if(player.isLooping()==false){
                        player.release();
                        player = null;
                    }
                }
            });
            player.setOnPreparedListener(new OnPreparedListener() {

                @Override
                public void onPrepared(MediaPlayer mp) {
                    player.start();
                }
            });
        }
    }
    public void pause(){
        if(player!=null && player.isPlaying()){
            player.pause();
        }
    }
    public void play(){
        if(player!=null && player.isPlaying()==false){
            player.start();
        }
    }
    public boolean isPlaying(){
        return player.isPlaying();
    }
    public void release(){
        if(player!=null){
            player.release();
        }
    }

}

修改下面的课程接收音频列表，然后播放第一个音频。当用户拨打startNextAudio()时，它会播放下一个音频。您可以根据需要使用其中任何一个

公共类AudioPlayer { MediaPlayer player = null; ArrayList playlist = null; int position = 0;

public AudioPlayer() { super(); // TODO Auto-generated constructor stub } public void startPlayingPlaylist(ArrayList<String> list){ playlist = list; if(player!=null){ player.release(); } if(playlist!=null && playlist.size()>0){ player = MediaPlayer.create(LMApplicaton.getInstance(),Uri.parse(playlist.get(position))); player.setWakeMode(LMApplicaton.getInstance(), PowerManager.PARTIAL_WAKE_LOCK); player.start(); // Set onCompletion listener player.setOnPreparedListener(new OnPreparedListener() { @Override public void onPrepared(MediaPlayer mp) { player.start(); } }); } } public void startNextAudio(){ position = position+1; if(position<playlist.size()){ try { player.reset(); player.setDataSource(playlist.get(position)); player.prepareAsync(); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (IllegalStateException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } else if(player.isLooping()==true){ position = position%playlist.size(); try { player.reset(); player.setDataSource(playlist.get(position)); player.prepareAsync(); } catch (IllegalArgumentException e) { e.printStackTrace(); } catch (IllegalStateException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } }else{ Log.i("AudioPlayer","Playlist reached at the end"); } } public void pause(){ if(player!=null && player.isPlaying()){ player.pause(); } } public void play(){ if(player!=null && player.isPlaying()==false){ player.start(); } } public boolean isPlaying(){ return player.isPlaying(); } public void release(){ if(player!=null){ player.release(); } }

}

Answer 2

一种方法是实现MediaPlayer.OnCompletionListener接口。这为您提供了MediaPlayer.onCompletion（）回调方法，您可以这样使用：

@Override
public void onCompletion(MediaPlayer mp) {
  if (i.hasNext) {
    // ...hand mp the next file
    // ...show the user the 'play next' button
  }
}

请注意，您还需要在设置中调用MediaPlayer.setOnCompletionListener()方法。

Android：立即停止播放声音文件

2 个答案: