我有这个适配器在按钮单击时播放音乐。当我单击已经播放的歌曲停止时，一切正常，应用程序崩溃。有人可以帮我解决这个问题 - 我现在想弄清楚两个小时。
这是我的适配器
public class DownloadsDetailsAdapter extends BaseAdapter {
private Activity activity;
private ArrayList<Songs> data;
private static LayoutInflater inflater = null;
private MediaPlayer mediaPlayer;
private ImageView playSong;
private String id;
private DatabaseHelper helper;
private ImageLoader loader;
private int oldPosition = -1;
private AsyncTask<Void, Void, Void> task;
Handler handler = new Handler();
public DownloadsDetailsAdapter(Activity a, ArrayList<Songs> songs, String id) {
activity = a;
data = songs;
this.id = id;
loader = new ImageLoader(a);
mediaPlayer = new MediaPlayer();
inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
public int getCount() {
return data.size();
}
public Object getItem(int position) {
return position;
}
public void stopMusic() {
try {
mediaPlayer.stop();
if (task.isCancelled() == false)
task.cancel(true);
playSong.setBackgroundResource(R.drawable.play_nr);
} catch (Exception e) {
}
}
public long getItemId(int position) {
return position;
}
public View getView(final int position, View convertView, ViewGroup parent) {
View vi = convertView;
if (convertView == null)
vi = inflater.inflate(R.layout.downloads_details_item, parent,
false);
helper = new DatabaseHelper(activity);
helper.openDB();
TextView songNumber = (TextView) vi
.findViewById(R.id.down_songs_item_number);
TextView albumTitle = (TextView) vi
.findViewById(R.id.down_songs_item_album_title);
TextView singer = (TextView) vi
.findViewById(R.id.down_songs_item_album_singer);
ImageView deleteSong = (ImageView) vi
.findViewById(R.id.down_songs_item_del);
ImageView thumb = (ImageView) vi
.findViewById(R.id.down_songs_item_thumb);
TextView feat = (TextView) vi
.findViewById(R.id.down_songs_item_album_feat);
loader.DisplayImage(data.get(position).getSONG_THUMB(), thumb);
playSong = (ImageView) vi.findViewById(R.id.down_songs_item_download);
if (!data.get(position).getIsPlaying())
playSong.setBackgroundResource(R.drawable.play_downloaded_album);
else
playSong.setBackgroundResource(R.drawable.stop);
albumTitle.setText(data.get(position).getSONG_TITLE());
singer.setText(data.get(position).getSONG_ARTIST());
// feat.setText(data.get(position).getFeat());
// if(data.get(position).getFeat().length()<=1)
feat.setVisibility(View.GONE);
songNumber.setText(position + 1 + "");
if (!data.get(position).getSONG_MP3()
.equals("http://nelu.burduja.com/musica/songs_with/")) {
deleteSong.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
if (!helper.isDBOpen()) {
helper.openDB();
}
DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
if (!helper.isDBOpen()) {
helper.openDB();
}
helper.removeDownloadedSong(id,
data.get(position).getSONG_TITLE());
helper.removeSharedSong(data.get(position)
.getSONG_TITLE(), id);
File file = new File(data.get(position)
.getSONG_MP3());
file.delete();
if (helper.getDownloadedSongsForAlbum(id)
.size() < 1) {
helper.removeDownloadedAlbum(id);
}
Toast.makeText(activity, R.string.song_deleted,
Toast.LENGTH_SHORT).show();
helper.closeDB();
break;
case DialogInterface.BUTTON_NEGATIVE:
dialog.dismiss();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(
activity);
builder.setMessage(R.string.are_you_sure)
.setPositiveButton(R.string.yes,
dialogClickListener)
.setNegativeButton(R.string.no, dialogClickListener)
.show();
helper.closeDB();
}
});
playSong.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
final ProgressDialog bufferingDialog = new ProgressDialog(
activity);
// ((DownloadedDetails) activity).changePicToPlay(position);
if (task != null && mediaPlayer != null) {
task.cancel(true);
mediaPlayer.release();
if (oldPosition != -1) {
((DownloadedDetails) activity)
.changePicToPlay(oldPosition);
}
}
if (position != oldPosition) {
((DownloadedDetails) activity)
.changePicToPlay(position);
task = new AsyncTask<Void, Void, Void>() {
@Override
protected void onPreExecute() {
bufferingDialog.setMessage(activity
.getString(R.string.buffering));
bufferingDialog.show();
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
try {
mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(data
.get(position).getSONG_MP3());
mediaPlayer.prepare();
mediaPlayer.start();
// handler.post(new Runnable() {
//
// @Override
// public void run() {
// ((DownloadedDetails) activity)
// .changePicToPlay(position);
// }
// });
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
bufferingDialog.dismiss();
((DownloadedDetails) activity)
.changePicToPlay(position);
handler.post(new Runnable() {
@Override
public void run() {
// ((DownloadedDetails) activity)
// .changePicToPlay(position);
Toast.makeText(activity,
"Song not existing",
Toast.LENGTH_SHORT).show();
}
});
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void result) {
if (bufferingDialog.isShowing())
bufferingDialog.dismiss();
super.onPostExecute(result);
}
};
task.execute();
} else {
if (data.get(position).getIsPlaying()==false) {
Log.v("--", "test0");
task = new AsyncTask<Void, Void, Void>() {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected Void doInBackground(Void... params) {
try {
mediaPlayer = new MediaPlayer();
mediaPlayer.setDataSource(data.get(
position).getSONG_MP3());
mediaPlayer.prepare();
mediaPlayer.start();
((DownloadedDetails) activity)
.changePicToPlay(position);
handler.post(new Runnable() {
@Override
public void run() {
}
});
// mediaPlayer.setOnCompletionListener(new OnCompletionListener() {
//
// @Override
// public void onCompletion(MediaPlayer mp) {
// ((DownloadedDetails) activity)
// .changePicToPlay(position);
// }
// });
} catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
((DownloadedDetails) activity)
.changePicToPlay(position);
handler.post(new Runnable() {
@Override
public void run() {
Toast.makeText(activity,
"Song not existing",
Toast.LENGTH_SHORT)
.show();
stopMusic();
}
});
}
// mediaPlayer.start();
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
}
};
task.execute();
} else {
Log.v("--", "test1");
task.cancel(false);
((DownloadedDetails) activity)
.changePicToPlay(position);
handler.post(new Runnable() {
@Override
public void run() {
playSong.setBackgroundResource(R.drawable.play_downloaded_album);
Log.v("--", "test2");
}
});
Log.v("--", "test3");
}
}
oldPosition = position;
}
});
}
helper.closeDB();
return vi;
}
}
这是日志猫：
09-06 00:55:23.593: E/AndroidRuntime(15814): FATAL EXCEPTION: AsyncTask #5
09-06 00:55:23.593: E/AndroidRuntime(15814): java.lang.RuntimeException: An error occured while executing doInBackground()
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.os.AsyncTask$3.done(AsyncTask.java:278)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.lang.Thread.run(Thread.java:856)
09-06 00:55:23.593: E/AndroidRuntime(15814): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:4056)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.ViewRootImpl.requestLayout(ViewRootImpl.java:709)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.View.requestLayout(View.java:12833)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.View.requestLayout(View.java:12833)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.View.requestLayout(View.java:12833)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.View.requestLayout(View.java:12833)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.widget.RelativeLayout.requestLayout(RelativeLayout.java:273)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.view.View.requestLayout(View.java:12833)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.widget.AbsListView.requestLayout(AbsListView.java:1697)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.widget.AdapterView$AdapterDataSetObserver.onChanged(AdapterView.java:801)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.widget.AbsListView$AdapterDataSetObserver.onChanged(AbsListView.java:5613)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.database.DataSetObservable.notifyChanged(DataSetObservable.java:35)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.widget.BaseAdapter.notifyDataSetChanged(BaseAdapter.java:50)
09-06 00:55:23.593: E/AndroidRuntime(15814): at com.outsourcefarm.musicagratis.activities.DownloadedDetails.changePicToPlay(DownloadedDetails.java:151)
09-06 00:55:23.593: E/AndroidRuntime(15814): at com.outsoucefarm.musicagratis.functions.DownloadsDetailsAdapter$2$2.doInBackground(DownloadsDetailsAdapter.java:258)
09-06 00:55:23.593: E/AndroidRuntime(15814): at com.outsoucefarm.musicagratis.functions.DownloadsDetailsAdapter$2$2.doInBackground(DownloadsDetailsAdapter.java:1)
09-06 00:55:23.593: E/AndroidRuntime(15814): at android.os.AsyncTask$2.call(AsyncTask.java:264)
09-06 00:55:23.593: E/AndroidRuntime(15814): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-06 00:55:23.593: E/AndroidRuntime(15814): ... 5 more
这是专辑详情第 151 行
public void changePicToPlay(int position) {
songs.get(position).togglePlaying();
adapter.notifyDataSetChanged();
}