Question

有人可以告诉我或教我如何在一个文件中下载5个或更多的mp3并在我的应用程序中播放它们。我搜索过它，但所有人都问过这个，没有什么能解释清楚。我不想只下载一个mp3，而是在文件中下载多个mp3。这是main.java

public class StreamingMp3Player extends Activity implements OnClickListener, OnTouchListener, OnCompletionListener, OnBufferingUpdateListener{

private ImageButton buttonPlayPause;
private SeekBar seekBarProgress;
public EditText editTextSongURL;

private MediaPlayer mediaPlayer;
private int mediaFileLengthInMilliseconds; // this value contains the song duration in milliseconds. Look at getDuration() method in MediaPlayer class

private final Handler handler = new Handler();

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    initView();
}

/** This method initialise all the views in project*/
private void initView() {
    buttonPlayPause = (ImageButton)findViewById(R.id.ButtonTestPlayPause);
    buttonPlayPause.setOnClickListener(this);

    seekBarProgress = (SeekBar)findViewById(R.id.SeekBarTestPlay);  
    seekBarProgress.setMax(99); // It means 100% .0-99
    seekBarProgress.setOnTouchListener(this);
    editTextSongURL = (EditText)findViewById(R.id.EditTextSongURL);
    editTextSongURL.setText(R.string.testsong_20_sec);

    mediaPlayer = new MediaPlayer();
    mediaPlayer.setOnBufferingUpdateListener(this);
    mediaPlayer.setOnCompletionListener(this);
}

/** Method which updates the SeekBar primary progress by current song playing position*/
private void primarySeekBarProgressUpdater() {
    seekBarProgress.setProgress((int)(((float)mediaPlayer.getCurrentPosition()/mediaFileLengthInMilliseconds)*100)); // This math construction give a percentage of "was playing"/"song length"
    if (mediaPlayer.isPlaying()) {
        Runnable notification = new Runnable() {
            public void run() {
                primarySeekBarProgressUpdater();
            }
        };
        handler.postDelayed(notification,1000);
    }
}

@Override
public void onClick(View v) {
    if(v.getId() == R.id.ButtonTestPlayPause){
         /** ImageButton onClick event handler. Method which start/pause mediaplayer playing */
        try {
            mediaPlayer.setDataSource(editTextSongURL.getText().toString()); // setup song from http://www.hrupin.com/wp-content/uploads/mp3/testsong_20_sec.mp3 URL to mediaplayer data source
            mediaPlayer.prepare(); // you must call this method after setup the datasource in setDataSource method. After calling prepare() the instance of MediaPlayer starts load data from URL to internal buffer. 
        } catch (Exception e) {
            e.printStackTrace();
        }

        mediaFileLengthInMilliseconds = mediaPlayer.getDuration(); // gets the song length in milliseconds from URL

        if(!mediaPlayer.isPlaying()){
            mediaPlayer.start();
            buttonPlayPause.setImageResource(R.drawable.button_pause);
        }else {
            mediaPlayer.pause();
            buttonPlayPause.setImageResource(R.drawable.button_play);
        }

        primarySeekBarProgressUpdater();
    }
}

@Override
public boolean onTouch(View v, MotionEvent event) {
    if(v.getId() == R.id.SeekBarTestPlay){
        /** Seekbar onTouch event handler. Method which seeks MediaPlayer to seekBar primary progress position*/
        if(mediaPlayer.isPlaying()){
            SeekBar sb = (SeekBar)v;
            int playPositionInMillisecconds = (mediaFileLengthInMilliseconds / 100) * sb.getProgress();
            mediaPlayer.seekTo(playPositionInMillisecconds);
        }
    }
    return false;
}

@Override
public void onCompletion(MediaPlayer mp) {
     /** MediaPlayer onCompletion event handler. Method which calls then song playing is complete*/
    buttonPlayPause.setImageResource(R.drawable.button_play);
}

@Override
public void onBufferingUpdate(MediaPlayer mp, int percent) {
    /** Method which updates the SeekBar secondary progress by current song loading from URL position*/
    seekBarProgress.setSecondaryProgress(percent);
}

Answer 1

您需要使用第三方库来支持MP3播放，因为它不包含在标准库中。有关备选方案的列表，请参阅Wikipedia。

对于下载部分，请使用URLConnection在文件上获取InputStream并将其写入FileOutputStream。这也可能有所帮助：Working unbuffered Streams

如何下载mp3文件并在我的应用程序中播放？

1 个答案: