I feel very stupid about this, watched multiple Tutorials and Stackoverflow questions, but still can't fix it.
I'm writing a very simple Android mp3 Stream listener. I want to use a Sevice so the Stream can be running in the Background. But i can't start a Service:
12-22 08:42:58.738: W/dalvikvm(1701): threadid=1: thread exiting with uncaught exception (group=0xb3aa2ba8)
12-22 08:42:58.788: E/AndroidRuntime(1701): FATAL EXCEPTION: main 12-22 08:42:58.788: E/AndroidRuntime(1701): Process: com.wankoradio, PID: 1701 12-22 08:42:58.788: E/AndroidRuntime(1701): java.lang.RuntimeException: Unable to instantiate service com.wankoradio.MediaPlayerService: java.lang.NullPointerException 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.app.ActivityThread.handleCreateService(ActivityThread.java:2556) 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.app.ActivityThread.access$1800(ActivityThread.java:135) 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278) 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.os.Handler.dispatchMessage(Handler.java:102) 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.os.Looper.loop(Looper.java:136) 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.app.ActivityThread.main(ActivityThread.java:5017) 12-22 08:42:58.788: E/AndroidRuntime(1701): at j ava.lang.reflect.Method.invokeNative(Native Method) 12-22 08:42:58.788: E/AndroidRuntime(1701): at java.lang.reflect.Method.invoke(Method.java:515) 12-22 08:42:58.788: E/AndroidRuntime(1701): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 12-22 08:42:58.788: E/AndroidRuntime(1701): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 12-22 08:42:58.788: E/AndroidRuntime(1701): at dalvik.system.NativeStart.main(Native Method) 12-22 08:42:58.788: E/AndroidRuntime(1701): Caused by: java.lang.NullPointerException 12-22 08:42:58.788: E/AndroidRuntime(1701): at android.content.ContextWrapper.getSystemService(ContextWrapper.java:540) 12-22 08:42:58.788: E/AndroidRuntime(1701): at com.wankoradio.MediaPlayerService.(MediaPlayerService.java:27)
etc
My MainActivity is starting the Service and looks kinda like this:
public class MainActivity extends Activity implements OnClickListener {
private Button pausePlayButton;
private static String ACTION_PLAY = "com.action.PLAY";
private MediaPlayer mediaPlayer;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
pausePlayButton = (Button) findViewById(R.id.pausePlay_Button);
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
pausePlayButton.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (!isPlaying) {
pausePlayButton.setBackgroundResource(R.drawable.button_pause);
Intent mServiceIntent = new Intent(getApplicationContext(), MediaPlayerService.class);
mServiceIntent.setAction(ACTION_PLAY);
startService(mServiceIntent);
and my Service looks like this:
public class MediaPlayerService extends Service implements MediaPlayer.OnPreparedListener, MediaPlayer.OnErrorListener {
//Creating a matching Intent
private static final String ACTION_PLAY = "com.action.PLAY";
//Creating our main MediaPlayer
MediaPlayer mMediaPlayer = null;
//NotificationID
private static final int NOTIFICATION_ID = 1234;
//Wifi should not be shut down while our App is running, therefore we Lock it
WifiLock wifiLock = ((WifiManager) getSystemService(Context.WIFI_SERVICE))
.createWifiLock(WifiManager.WIFI_MODE_FULL, "mylock");
@Override
public void onCreate() {
super.onCreate();
Notification notification = StartNotification();
startForeground(NOTIFICATION_ID, notification);
}
public int onStartCommand(Intent intent, int flags, int startId) {
if (intent.getAction().equals(ACTION_PLAY)) {
//Wifi should not be shut down while our App is running, therefore we Lock it
wifiLock.acquire();
StartMediaPlayer();
}
return 0;
}
private Notification StartNotification() {
String songName = "Woop";
// assign the song name to songName
PendingIntent pi = PendingIntent.getActivity(getApplicationContext(), 0,
new Intent(getApplicationContext(), MainActivity.class),
PendingIntent.FLAG_UPDATE_CURRENT);
Notification notification = new Notification();
//notification.tickerText = text;
//notification.icon = R.drawable.play0;
notification.flags |= Notification.FLAG_ONGOING_EVENT;
NotificationManager notificationManager = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
notificationManager.notify(NOTIFICATION_ID, notification);
return notification;
}
I tried to debug it but onCreate or onStartCommand of my Service won't get called
and here is my Manifest:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.wankoradio.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<service
android:enabled="true"
android:name=".MediaPlayerService"
android:label="MediaPlayer Service" >
<intent-filter>
<action
android:name = "com.action.PLAY">
</action>
</intent-filter>
</service>
<receiver
android:name=".MainActivity">
<intent-filter>
<action
android:name = "com.action.PLAY">
</action>
</intent-filter>
</receiver>
</application>
I'm sorry if I'm wasting your time, this is my first Android application, on WinPhone this is certainly easier to do.
WifiLock wifiLock = ((WifiManager) getSystemService(Context.WIFI_SERVICE))
.createWifiLock(WifiManager.WIFI_MODE_FULL, "mylock");
System services are not available at object instantiation time. Postpone initializing your wifiLock
to onCreate()
or later.
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