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這是我第一次發佈在stackoverflow上，所以請裸照我。（Android）無法使用MusicService在片段中播放音樂
我有一個片段，它給了我存儲在手機上的所有歌曲的listView。當我點擊列表中的特定歌曲時，我應該可以使用MusicService播放它。
當選擇特定的抽屜項目時，此片段（menu2_Fragment）在ActionBarActivity中初始化。請參見下面的代碼：
@Override
public void onNavigationDrawerItemSelected(int position) {
Fragment objFragment = null;
switch(position){
case 0:
objFragment = new menu1_Fragment();
getSupportActionBar().setTitle("Scan for Users");
break;
case 1:
objFragment = new menu2_Fragment();
getSupportActionBar().setTitle("Your Music");
// objFragment = new MyMusicFragment();
break;
case 2:
objFragment = new menu3_Fragment();
getSupportActionBar().setTitle("Popular Music");
}
// update the main content by replacing fragments
FragmentManager fragmentManager = getSupportFragmentManager();
fragmentManager.beginTransaction()
.replace(R.id.container, objFragment)
.commit();
}
這是片段代碼：
package com.example.cs446.soundscope;
import android.content.ComponentName;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.IBinder;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.MediaController;
import com.example.cs446.soundscope.Adapter.SongAdapter;
import com.example.cs446.soundscope.data.Song;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
/**
* Created by val on 27/02/15.
*/
public class menu2_Fragment extends Fragment implements MediaController.MediaPlayerControl{
View rootview;
private ArrayList<Song> songList;
private ListView songView;
private MusicService musicSrv;
private Intent playIntent;
private boolean musicBound=false;
private MusicController controller;
private boolean paused=false;
private boolean playbackPaused=false;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
rootview = inflater.inflate(R.layout.activity_main,container, false);
songView = (ListView)rootview.findViewById(R.id.song_list);
songList = new ArrayList<Song>();
getSongList();
//sort all of the songList by title
Collections.sort(songList, new Comparator<Song>() {
//function that does the sorting
@Override
public int compare(Song lhs, Song rhs) {
return lhs.getTitle().compareTo(rhs.getTitle());
}
});
SongAdapter songAdt = new SongAdapter(getActivity(),songList);
songView.setAdapter(songAdt);
setController();
//startActivity(new Intent(this, MainActivity.class));
return rootview;
}
//get the song information for your filesystem
public void getSongList(){
//use the contentResolver to retrieve the uri for the music file
//a cursor instance is created with the contentResolver
ContentResolver musicResolver = this.getActivity().getContentResolver();
Uri musicUri = android.provider.MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
Cursor musicCursor = musicResolver.query(musicUri, null, null, null, null);
//store the songs into the song list array list
if(musicCursor!=null && musicCursor.moveToFirst()){
//get columns
int titleColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.TITLE);
int idColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media._ID);
int artistColumn = musicCursor.getColumnIndex
(android.provider.MediaStore.Audio.Media.ARTIST);
//add songs to list
do {
long thisId = musicCursor.getLong(idColumn);
String thisTitle = musicCursor.getString(titleColumn);
String thisArtist = musicCursor.getString(artistColumn);
songList.add(new Song(thisId, thisTitle, thisArtist));
}
while (musicCursor.moveToNext());
}
}
public void songPicked(View view){
musicSrv.setSong(Integer.parseInt(view.getTag().toString()));
musicSrv.playSong();
if(playbackPaused){
setController();
playbackPaused=false;
}
controller.show(0);
}
//set the controller up
private void setController(){
controller = new MusicController(getActivity());
controller.setPrevNextListeners(new View.OnClickListener() {
@Override
public void onClick(View v) {
playNext();
}
}, new View.OnClickListener() {
@Override
public void onClick(View v) {
playPrev();
}
});
controller.setMediaPlayer(this);
controller.setAnchorView(getActivity().findViewById(R.id.song_list));
controller.setEnabled(true);
}
@Override
public void onStart() {
super.onStart();
if(playIntent==null){
playIntent = new Intent(getActivity(), MusicService.class);
this.getActivity().bindService(playIntent, musicConnection, Context.BIND_AUTO_CREATE);
this.getActivity().startService(playIntent);
}
}
@Override
public void onPause(){
super.onPause();
paused=true;
}
@Override
public void onResume(){
super.onResume();
if(paused){
setController();
paused=false;
}
}
@Override
public void onStop() {
controller.hide();
super.onStop();
}
//connect to the service
private ServiceConnection musicConnection = new ServiceConnection(){
@Override
public void onServiceConnected(ComponentName name, IBinder service) {
MusicService.MusicBinder binder = (MusicService.MusicBinder)service;
//get service
musicSrv = binder.getService();
//pass list
musicSrv.setList(songList);
musicBound = true;
}
@Override
public void onServiceDisconnected(ComponentName name) {
musicBound = false;
}
};
//play next
private void playNext(){
musicSrv.playNext();
if(playbackPaused){
setController();
playbackPaused=false;
}
controller.show(0);
}
//play previous
private void playPrev(){
musicSrv.playPrev();
if(playbackPaused){
setController();
playbackPaused=false;
}
controller.show(0);
}
@Override
public void onDestroy() {
this.getActivity().stopService(playIntent);
musicSrv=null;
super.onDestroy();
}
@Override
public void start() {
musicSrv.go();
}
@Override
public void pause() {
playbackPaused=true;
musicSrv.pausePlayer();
}
@Override
public int getDuration() {
if(musicSrv!=null && musicBound && musicSrv.isPng())
return musicSrv.getDur();
else return 0;
}
@Override
public int getCurrentPosition() {
if(musicSrv!=null && musicBound && musicSrv.isPng())
return musicSrv.getPosn();
else return 0;
}
@Override
public void seekTo(int pos) {
musicSrv.seek(pos);
}
@Override
public boolean isPlaying() {
if(musicSrv!=null && musicBound)
return musicSrv.isPng();
return false;
}
@Override
public int getBufferPercentage() {
return 0;
}
@Override
public boolean canPause() {
return true;
}
@Override
public boolean canSeekBackward() {
return true;
}
@Override
public boolean canSeekForward() {
return true;
}
@Override
public int getAudioSessionId() {
return 0;
}
}
當我在ListView一個項目點擊，而不是播放的歌曲我的應用程序崩潰，我收到以下錯誤信息：
03-02 00:46:29.142 6485-6485/com.example.cs446.soundscope E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.cs446.soundscope, PID: 6485
java.lang.IllegalStateException: Could not find a method songPicked(View) in the activity class com.example.cs446.soundscope.ListNearbyUsers for onClick handler on view class android.widget.LinearLayout
at android.view.View$1.onClick(View.java:3994)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.NoSuchMethodException: songPicked [class android.view.View]
at java.lang.Class.getMethod(Class.java:664)
at java.lang.Class.getMethod(Class.java:643)
at android.view.View$1.onClick(View.java:3987)
at android.view.View.performClick(View.java:4756)
at android.view.View$PerformClick.run(View.java:19749)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
當播放音樂功能正常工作時沒有在Fragment中實現，而是在Activity中實現。有沒有人看到過這樣的錯誤？如果是這樣，我會很感激一些指導。
對於術語中的任何誤用我表示歉意我最近開始學習android開發。