URL cannot be wrapped to String

Question

I am very new to android and trying to develop an application for downloading all mp3 files from the server to view the list, and by clicking on the list item, it should play this mp3 file directly from the server.

Somehow I can list all mp3 files from the server to view the list, but when I click on the list item to play this song, it gives me the following error.

Logcat

02-18 11:49:58.266: E/AndroidRuntime(8276): FATAL EXCEPTION: main
02-18 11:49:58.266: E/AndroidRuntime(8276): java.lang.ClassCastException: java.net.URL cannot be cast to java.lang.String
02-18 11:49:58.266: E/AndroidRuntime(8276):     at iqual.fidol_final.ServerFileList$1.onItemClick(ServerFileList.java:72)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.widget.AdapterView.performItemClick(AdapterView.java:295)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.widget.AbsListView.performItemClick(AbsListView.java:1073)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.widget.AbsListView$PerformClick.run(AbsListView.java:2577)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.widget.AbsListView$1.run(AbsListView.java:3302)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.os.Handler.handleCallback(Handler.java:605)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.os.Handler.dispatchMessage(Handler.java:92)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.os.Looper.loop(Looper.java:154)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at android.app.ActivityThread.main(ActivityThread.java:4624)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at java.lang.reflect.Method.invokeNative(Native Method)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at java.lang.reflect.Method.invoke(Method.java:511)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:809)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:576)
02-18 11:49:58.266: E/AndroidRuntime(8276):     at dalvik.system.NativeStart.main(Native Method)

Java code

public class ServerFileList extends Activity implements
        OnBufferingUpdateListener, OnErrorListener, OnPreparedListener {

    Uri uri;
    URL urlAudio;
    ListView mListView;
    PlaySongAsy play;

    ProgressDialog pDialog;
    JSONParser jParser = new JSONParser();
    MediaPlayer mp = new MediaPlayer();
    private List<String> myList = new ArrayList<String>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        super.onCreate(savedInstanceState);
        setContentView(R.layout.serverfilelist);

        mListView = (ListView) findViewById(R.id.listAudio);

        if (Const.server == 0) {
            new getAudiofromServer().execute();
        } else {
            new getVideofromServer().execute();
        }

        // new downloadAudio().execute();

        mListView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // playSong(urlAudio + myList.get(position));
                play = (PlaySongAsy) new PlaySongAsy(myList.get(position)
                        .replace(" ", "%20").trim()).execute();
            }
        });
    }

    class PlaySongAsy extends AsyncTask<String, Void, Boolean> {

        String baseURL;

        public PlaySongAsy(String baseURL) {
            this.baseURL = baseURL;
        }

        @Override
        protected void onPreExecute() {
            // TODO Auto-generated method stub
            super.onPreExecute();
            pDialog = ProgressDialog.show(ServerFileList.this,
                    "    Buffering...", "please wait..", false);
            pDialog.setCancelable(false);

        }

        @Override
        protected Boolean doInBackground(String... urls) {
            new Thread() {
                @Override
                public void run() {
                    play(baseURL);
                }
            }.start();
            return true;
        }

        @Override
        protected void onPostExecute(Boolean result) {
            super.onPostExecute(result);
            // progressDialog.dismiss();
        }
    }

    private void play(String baseURL) {
        Uri myUri = Uri.parse(baseURL);
        try {
            if (mp == null) {
                this.mp = new MediaPlayer();
            } else {
                mp.stop();
                mp.reset();
            }
            mp.setDataSource(this, myUri); // Go to Initialized state

            mp.setAudioStreamType(AudioManager.STREAM_MUSIC);
            mp.setOnPreparedListener(this);
            mp.setOnBufferingUpdateListener(this);
            mp.setOnErrorListener(this);

            mp.prepareAsync();

            // mp.setVolume(5.F, 5.F);

            Log.d("", "LoadClip Done");
        } catch (Throwable t) {
            Log.d("", t.toString());
        }
    }

    public void updateProgress(int currentSize, int totalSize) {
        TextView mTextView = new TextView(ServerFileList.this);
        mTextView.setText(Long.toString((currentSize / totalSize) * 100) + "%");
    }
    }

Answer 1

Code:

myList.get(position)

myList String, myList List<String>. , URL myList.

"unchecked cast", , myList.

:

• . , , .toString() URL, myList.

• myList List<URL>, .toString() onItemClick.

, , myList.

Answer 2

toString() URL, . . http://docs.oracle.com/javase/6/docs/api/java/net/URL.html#toString%28%29

Answer 3

, myList . URI, Strings. toString URI .

, :

myList.add((String)uri);

:

myList.add(uri.toString());

Answer 4

...

java.lang.ClassCastException: java.net.URL cannot be cast to java.lang.String

, URL String... , baseURL URL, String, Exception .

...

String baseURL;

Uri baseURL;

, baseURL String, Uri.

Answer 5

Try to remove all unnecessary spaces in your URL by calling trim(). See also question below.

Android: howto parse URL String with spaces for a URI?