问题
after trying my brand new service on android i get this:
i guess is something related to the manifest file and permissions, the service is started after the last activity, to update data on server and retrieve new data and save id on sqlite on android:
here also the manifest file:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.ggservice.democracy"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET"/>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.ggservice.democracy.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>
<activity android:label="@string/app_name" android:name="com.ggservice.democracy.sondaggioActivity"/>
<activity android:label="@string/app_name" android:name="com.ggservice.democracy.domandeDiCategoria"/>
<service android:name="com.ggservice.democracy.updateDemocracyService" />
</application>
</manifest>
the logcat:
01-02 15:33:30.960: W/dalvikvm(2570): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
01-02 15:33:31.160: E/AndroidRuntime(2570): FATAL EXCEPTION: main
01-02 15:33:31.160: E/AndroidRuntime(2570): java.lang.RuntimeException: Unable to start service com.ggservice.democracy.updateDemocracyService@412f0c60 with Intent { cmp=com.ggservice.democracy/.updateDemocracyService }: android.os.NetworkOnMainThreadException
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2376)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.app.ActivityThread.access$1900(ActivityThread.java:123)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1210)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.os.Handler.dispatchMessage(Handler.java:99)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.os.Looper.loop(Looper.java:137)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.app.ActivityThread.main(ActivityThread.java:4424)
01-02 15:33:31.160: E/AndroidRuntime(2570): at java.lang.reflect.Method.invokeNative(Native Method)
01-02 15:33:31.160: E/AndroidRuntime(2570): at java.lang.reflect.Method.invoke(Method.java:511)
01-02 15:33:31.160: E/AndroidRuntime(2570): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
01-02 15:33:31.160: E/AndroidRuntime(2570): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
01-02 15:33:31.160: E/AndroidRuntime(2570): at dalvik.system.NativeStart.main(Native Method)
01-02 15:33:31.160: E/AndroidRuntime(2570): Caused by: android.os.NetworkOnMainThreadException
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
01-02 15:33:31.160: E/AndroidRuntime(2570): at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
01-02 15:33:31.160: E/AndroidRuntime(2570): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
01-02 15:33:31.160: E/AndroidRuntime(2570): at java.net.InetAddress.getAllByName(InetAddress.java:220)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
01-02 15:33:31.160: E/AndroidRuntime(2570): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
01-02 15:33:31.160: E/AndroidRuntime(2570): at com.ggservice.democracy.JSONParser.getJSONFromUrl(JSONParser.java:38)
01-02 15:33:31.160: E/AndroidRuntime(2570): at com.ggservice.democracy.updateDemocracyService.onStartCommand(updateDemocracyService.java:47)
01-02 15:33:31.160: E/AndroidRuntime(2570): at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:2359)
01-02 15:33:31.160: E/AndroidRuntime(2570): ... 10 more
am i doing something wrong?
this is also the service:
public class updateDemocracyService extends Service{
private pollDataSource datasource;
int mStartMode; // indicates how to behave if the service is killed
IBinder mBinder; // interface for clients that bind
boolean mAllowRebind; // indicates whether onRebind should be used
// url to make request
private static String url = "http://www.test.com/democracy/domande.php";
// JSON Node names
private static final String TAG_DOMANDE = "domande";
private static final String TAG_ID = "id";
private static final String TAG_TESTO = "testo";
// contacts JSONArray
JSONArray contacts = null;
@Override
public void onCreate() {
// The service is being created
datasource = new pollDataSource(this);
datasource.open();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// Creating JSON Parser instance
JSONParser jParser = new JSONParser();
// getting JSON string from URL
JSONObject json = jParser.getJSONFromUrl(url);
try {
// Getting Array of Contacts
contacts = json.getJSONArray(TAG_DOMANDE);
// looping through All Contacts
for(int i = 0; i < contacts.length(); i++){
JSONObject c = contacts.getJSONObject(i);
// Storing each json item in variable
String id = c.getString(TAG_ID);
String name = c.getString(TAG_TESTO);
datasource.createCategoria(name);
}
} catch (JSONException e) {
e.printStackTrace();
}
Toast.makeText(this, "ho comunicato con un server!", Toast.LENGTH_LONG).show();
return mStartMode;
}
@Override
public IBinder onBind(Intent intent) {
// A client is binding to the service with bindService()
return mBinder;
}
@Override
public boolean onUnbind(Intent intent) {
// All clients have unbound with unbindService()
return mAllowRebind;
}
@Override
public void onRebind(Intent intent) {
// A client is binding to the service with bindService(),
// after onUnbind() has already been called
}
@Override
public void onDestroy() {
datasource.close();
// The service is no longer used and is being destroyed
}
}
回答1:
This happens because you are doing a network operation on the main thread, and this is not allowed on Android 3.0 and above. Even though it is in a service, services are run on the UI thread unless you specifically launch them in another thread or create a thread inside it.
You can fix this by running the task in a service off the main UI thread, by using a Thread or an AsyncTask.
Try creating a new thread in onStartCommand(), as suggested by @CommonsWare.
回答2:
Create function:
Thread thread = new Thread(new Runnable(){
@Override
public void run() {
.......
}
});
And call it from onStartCommand
thread.start();
回答3:
As per the documentation, even though you use a Service to perform long running operations, the Service itself runs on the application's main thread. So you have to spawn a new thread to perform potentially long running tasks like network access.
Android's StrictMode actually checks for network operations performed on the main thread and throws a NetworkOnMainThreadException.
回答4:
Try this. How to fix android.os.NetworkOnMainThreadException?
Read this thread carefully.
I hope this will solve your problem.
来源：https://stackoverflow.com/questions/14124739/android-os-networkonmainthreadexception-on-service-start-on-android