将歌曲设置为铃声时Android写入文件问题

Question

我已经成功编写了一个程序，将歌曲设置为铃声，但面临一个非常小的问题

当我第一次点击按钮将歌曲设为铃声时，请点击此处：

但是当我再次点击按钮（第二次）时，得到这个：

那么可能是什么原因？为什么我第一次也没有成功......

以下是 RingtoneActivity.java 的完整代码：

    public class RingtoneActivity extends Activity {

    private final Context context = this;
    private static final String TAG = "Meri Desi Look";
    private File sound;
    private final File folder = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_RINGTONES);
    private MediaPlayer mediaPlayer;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button buttonRingtone = (Button) findViewById(R.id.btnRingtone);
        buttonRingtone.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                ask();
            }
        });
    }


    private void ask() {
        mediaPlayer = MediaPlayer.create(this, R.raw.meri_desi_look);
        mediaPlayer.start();
        AlertDialog.Builder alert = new AlertDialog.Builder(context);
        alert.setTitle("Meri Desi Look");
        alert.setMessage("You want this sound as your ringtone?");
        alert.setCancelable(false);
        alert.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int whichButton) {
                mediaPlayer.stop();
                mediaPlayer.reset();
                confirmed();
                dialog.dismiss();
            }
        });
        alert.setNegativeButton("No", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int whichButton) {
                mediaPlayer.stop();
                mediaPlayer.reset();
                dialog.dismiss();
            }
        });
        alert.show();
    }

    /**
     * When the user confirms the popup, this will run, saving the file and
     * setting the ringtone utilising the RingtoneManager class.
     */
    private void confirmed() {
        Boolean success = false;
        sound = new File(folder, "meri_desi_look.mp3");
        if (!sound.exists()) {
            Log.i(TAG, "Writing Meri Desi Look to " + folder.toString());
            try {
                InputStream in = getResources().openRawResource(R.raw.meri_desi_look);
                FileOutputStream out = new FileOutputStream(sound.getPath());
                byte[] buff = new byte[1024];
                int read = 0;

                try {
                    while ((read = in.read(buff)) > 0) {
                        out.write(buff, 0, read);
                    }
                } finally {
                    in.close();

                    out.close();
                }
            } catch (Exception e) {
                success = false;
                Log.i(TAG, "Desi Look failed to write.");
            }
        } else {
            success = true;
            Log.i(TAG, "Meri Desi Look ringtone already there.");
        }

        if (!success) {
            onSetRingtoneError("We couldn't give you a Meri Desi Look ringtone.\n\nThere's an issue writing the file.");
        } else {
            setRingtone();
        }
    }

    /**
     * Physically sets the RingtoneManager preferences.
     */
    private void setRingtone() {
        try {
            ContentValues values = new ContentValues();
            values.put(MediaStore.MediaColumns.DATA, sound.getAbsolutePath());
            values.put(MediaStore.MediaColumns.TITLE, "Meri Desi Look - performed by Sunny Leone");
            values.put(MediaStore.MediaColumns.MIME_TYPE, "audio/*");
            values.put(MediaStore.Audio.Media.ARTIST, "Meri Desi Look");
            values.put(MediaStore.Audio.Media.IS_RINGTONE, true);
            values.put(MediaStore.Audio.Media.IS_NOTIFICATION, true);
            values.put(MediaStore.Audio.Media.IS_ALARM, true);
            values.put(MediaStore.Audio.Media.IS_MUSIC, true);

            Uri uri = MediaStore.Audio.Media.getContentUriForPath(sound.getAbsolutePath());
            getContentResolver().delete(uri, MediaStore.MediaColumns.DATA + "=\"" + sound.getAbsolutePath() + "\"",
                    null);
            Uri newUri = getContentResolver().insert(uri, values);

            RingtoneManager.setActualDefaultRingtoneUri(context, RingtoneManager.TYPE_RINGTONE, newUri);
            onSetRingtoneSuccess();
        } catch (Exception e) {
            onSetRingtoneError("We couldn't give you a Meri Desi Look ringtone.\n\nThere's an issue setting the file.");
        }
    }

    /**
     * Generic helper to show error messages (if ever there are any) :p
     * 
     * @param message
     */
    private void onSetRingtoneError(String message) {
        AlertDialog.Builder alert = new AlertDialog.Builder(context);
        alert.setTitle("Meri Desi Look");
        alert.setMessage(message);
        alert.setCancelable(false);
        alert.setPositiveButton("OK. That's too bad.", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int whichButton) {
                dialog.dismiss();
            }
        });
        alert.show();
    }


    private void onSetRingtoneSuccess() {
        AlertDialog.Builder alert = new AlertDialog.Builder(context);
        alert.setTitle("Meri Desi Look");
        alert.setMessage("You've got the ringtone :)\n\nHope you enjoy it!");
        alert.setCancelable(false);
        alert.setPositiveButton("Sweet!", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int whichButton) {
                dialog.dismiss();
            }
        });
        alert.show();
    }

    @Override
    protected void onPause() {
        if (mediaPlayer.isPlaying()) {
            mediaPlayer.stop();
            mediaPlayer.release();
        }
        super.onPause();
    }

}

Answer 1

我认为你很久以前就已经想到了代码中存在问题的地方。但如果你没有，请尝试以下方法。

private void confirmed() { 
...

try {
      while ((read = in.read(buff)) > 0) {
      out.write(buff, 0, read);
    }
    success = true;
} 
catch(Exception e) {
     success = false;
     e.printStackTrace();
}
finally {
    n.close();
    out.close();
}
...

}