java - "setDataSource failed"异常

Question

我已经设法用音频文件填充我的 ListView，但是当单击 ListView 中的项目时没有任何反应，我收到异常“setDataSource failed”。

public class songsFragment extends Fragment {

    private static final int MY_PERMISSION_REQUEST = 1;
    ListView trackList;
    private RelativeLayout songs_layout;
    ArrayList<String> arrayList;
    ArrayAdapter<String> adapter;
    private MediaPlayer mp = new MediaPlayer();

    public songsFragment() {

    }

    public void doStuff() {

        arrayList = new ArrayList<>();
        getMusic();
        adapter = new ArrayAdapter<>(Objects.requireNonNull(getContext()), android.R.layout.simple_list_item_1, arrayList);
        trackList.setAdapter(adapter);

        trackList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int i, long I) {

                mp = new MediaPlayer();

                try {

                    mp.setDataSource(arrayList.get(i));
                    mp.prepare();
                    mp.start();

                } catch (IOException e) {

                    Log.v(getString(R.string.app_name),e.getMessage());

                }

            }
        });

    }

    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.songs_fragment, container, false);
        songs_layout = v.findViewById(R.id.songs_layout);
        return v;

    }

    @SuppressLint("ClickableViewAccessibility")
    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

        trackList = view.findViewById(R.id.songList);

        if (ContextCompat.checkSelfPermission(Objects.requireNonNull(getActivity()).getApplicationContext(),
                Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {

            if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(),
                    Manifest.permission.READ_EXTERNAL_STORAGE)) {

                ActivityCompat.requestPermissions(getActivity(),
                        new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, MY_PERMISSION_REQUEST);

            } else {

                ActivityCompat.requestPermissions(getActivity(),
                        new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, MY_PERMISSION_REQUEST);
            }

        } else {

            doStuff();

        }

        if (trackList.getParent() != null) {

            ((ViewGroup)trackList.getParent()).removeView(trackList);

        }

        songs_layout.addView(trackList);

    }

    public void getMusic() {

        ContentResolver contentResolver = Objects.requireNonNull(getContext()).getContentResolver();
        Uri songUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
        @SuppressLint("Recycle") Cursor songCursor = contentResolver.query
                (songUri, null,null,null,null);


        if (songCursor != null && songCursor.moveToFirst()) {

            int songTitle = songCursor.getColumnIndex(MediaStore.Audio.Media.TITLE);
            int songArtist = songCursor.getColumnIndex(MediaStore.Audio.Media.ARTIST);

            do {

                String currentTitle = songCursor.getString(songTitle);

                String currentArtist = songCursor.getString(songArtist);

                arrayList.add("\n" + currentTitle + "\n" + currentArtist + "\n");

            } while (songCursor.moveToNext());

        }

    }

    @Override
    public void onDestroy() {

        super.onDestroy();
        mp.release();

    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {

        switch (requestCode) {

            case MY_PERMISSION_REQUEST: {

                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                    if (ContextCompat.checkSelfPermission(Objects.requireNonNull(getActivity()).getApplicationContext(),
                            Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {

                        Toast.makeText(getContext(), "Permission granted", Toast.LENGTH_SHORT).show();

                        doStuff();

                    }

                } else {

                    Toast.makeText(getContext(),"No permission granted", Toast.LENGTH_SHORT).show();

                    Objects.requireNonNull(getActivity()).finish();

                }

            }

        }

    }

}

日志

2018-12-19 20:06:37.429 9793-9793/com.oladapo.jukebox W/System.err: java.io.IOException: setDataSource failed.
2018-12-19 20:06:37.442 9793-9793/com.oladapo.jukebox W/System.err:     at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1191)
2018-12-19 20:06:37.442 9793-9793/com.oladapo.jukebox W/System.err:     at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1164)
2018-12-19 20:06:37.442 9793-9793/com.oladapo.jukebox W/System.err:     at android.media.MediaPlayer.setDataSource(MediaPlayer.java:1131)
2018-12-19 20:06:37.442 9793-9793/com.oladapo.jukebox W/System.err:     at com.oladapo.jukebox.songsFragment$1.onItemClick(songsFragment.java:59)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.widget.AdapterView.performItemClick(AdapterView.java:318)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.widget.AbsListView.performItemClick(AbsListView.java:1159)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.widget.AbsListView$PerformClick.run(AbsListView.java:3136)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.widget.AbsListView$3.run(AbsListView.java:4052)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.os.Handler.handleCallback(Handler.java:873)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:99)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.os.Looper.loop(Looper.java:193)
2018-12-19 20:06:37.443 9793-9793/com.oladapo.jukebox W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:6718)
2018-12-19 20:06:37.444 9793-9793/com.oladapo.jukebox W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
2018-12-19 20:06:37.444 9793-9793/com.oladapo.jukebox W/System.err:     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
2018-12-19 20:06:37.444 9793-9793/com.oladapo.jukebox W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
2018-12-19 20:06:37.444 9793-9793/com.oladapo.jukebox V/Juke Box: setDataSource failed.

Answer 1

您在此处的数组列表中添加标题和艺术家姓名

arrayList.add("\n"+ currentTitle + "\n"+ currentArtist + "\n");

然后像这样添加数据源

mp.setDataSource(arrayList.get(i));

但是setDataSource需要文件路径，在您的情况下，arraylist 仅包含标题和艺术家姓名，这不是该 mp3 文件的路径。

这是例子。 https://www.programcreek.com/java-api-examples/?class=android.media.MediaPlayer&method=setDataSource