How do you play Android InputStream on MediaPlayer?

问题

So I have a small audio file in my assets folder and I wanted to open a InputStream to write to a buffer, then write to a temporary File, then I open up the MediaPlayer to play that temporary File. Problem is, when the media player hits mp.Prepare(), it doesn't play and never reaches the toast. Has anyone ever done this before?

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    InputStream str;

    try {

        str = this.getAssets().open("onestop.mid");
        Toast.makeText(this, "Successful Input Stream Opened.", Toast.LENGTH_SHORT).show();
        takeInputStream(str);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}//end on create

public void takeInputStream(InputStream stream) throws IOException
{
    //fileBeingBuffered = (FileInputStream) stream;
    //Toast.makeText(this, "sucessful stream conversion.", Toast.LENGTH_SHORT).show();
    try
    {
        convertedFile = File.createTempFile("convertedFile", ".dat", getDir("filez", 0));
        Toast.makeText(this, "Successful file and folder creation.", Toast.LENGTH_SHORT).show();

        out = new FileOutputStream(convertedFile);
        Toast.makeText(this, "Success out set as output stream.", Toast.LENGTH_SHORT).show();

        //RIGHT AROUND HERE -----------

        byte buffer[] = new byte[16384];
        int length = 0;
        while ( (length = stream.read(buffer)) != -1 ) 
        {
          out.write(buffer,0, length);
        }

        //stream.read(buffer);
        Toast.makeText(this, "Success buffer is filled.", Toast.LENGTH_SHORT).show();
        out.close();

        playFile();
    }catch(Exception e)
    {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    }//end catch
}//end grabBuffer

public void playFile()
{
    try {
        String path = convertedFile.getAbsolutePath();
        mp = new MediaPlayer();
        mp.setDataSource(path);
        Toast.makeText(this, "Success, Path has been set", Toast.LENGTH_SHORT).show();

        mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
        mp.prepare();
        Toast.makeText(this, "Media Player prepared", Toast.LENGTH_SHORT).show();

        mp.start();
        Toast.makeText(this, "Media Player playing", Toast.LENGTH_SHORT).show();
    } catch (IllegalArgumentException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    } catch (IllegalStateException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    } catch (IOException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    }

}//end playFile

回答1:

Fixed it. Turns out that after writing the buffer in the temporary file created by "File," you can then open that file using a FileInputStream, then proceed to play it shown below. Thanks for all your help guys.

mp = new MediaPlayer();

FileInputStream fis = new FileInputStream(convertedFile);
mp.setDataSource(fis.getFD());

Toast.makeText(this, "Success, Path has been set", Toast.LENGTH_SHORT).show();

mp.prepare();
mp.start();

回答2:

This is the code that worked for me

//preserved to stop previous actions 
MediaPlayer lastmp;

public void playSound(String file) {
    try {
        if (lastmp!=null) lastmp.stop();
        MediaPlayer mp = new MediaPlayer();
        lastmp = mp;
        AssetFileDescriptor descriptor;

        AssetManager assetManager = act.getAssets();

        descriptor =  assetManager.openFd(fileName);
        mp.setDataSource(descriptor.getFileDescriptor(), descriptor.getStartOffset(), descriptor.getLength());
        descriptor.close();
        mp.prepare();
        mp.start();

    } catch (Exception e) {
        e.printStackTrace();
    }
}

the file shoud be on the assets folder

来源：https://stackoverflow.com/questions/5747060/how-do-you-play-android-inputstream-on-mediaplayer

标签

android

file

inputstream

fileoutputstream