Causato da: android.os.NetworkOnMainThreadException

Question

Ciao a tutti gli spettatori e lettori, sto usando link. Ogni volta che eseguo questo codice in un pacchetto separato funziona correttamente, ma ogni volta che cerco di incorporare questo esempio nella mia app, l'app Purtroppo si ferma, solo quando faccio clic sulla scheda in quella particolare scheda che la chiama, e Logcat dice: -

Caused by: android.os.NetworkOnMainThreadException 
10-30 15:07:35.341: E/AndroidRuntime(732): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117), 

per favore dimmi che cosa ho bisogno di renderlo utile per me, tranne questa particolare scheda intera applicazione funziona bene.

10-30 15:07:26.770: D/dalvikvm(732): GC_FOR_ALLOC freed 61K, 3% free 8035K/8259K, paused 39ms, total 46ms 
    10-30 15:07:26.781: I/dalvikvm-heap(732): Grow heap (frag case) to 8.481MB for 614416-byte allocation 
    10-30 15:07:26.850: D/dalvikvm(732): GC_CONCURRENT freed 1K, 4% free 8634K/8903K, paused 27ms+13ms, total 71ms 
    10-30 15:07:26.881: D/dalvikvm(732): GC_FOR_ALLOC freed 0K, 4% free 8634K/8903K, paused 28ms, total 28ms 
    10-30 15:07:26.900: I/dalvikvm-heap(732): Grow heap (frag case) to 9.798MB for 1382416-byte allocation 
    10-30 15:07:26.970: D/dalvikvm(732): GC_CONCURRENT freed 0K, 4% free 9984K/10311K, paused 28ms+5ms, total 72ms 
    10-30 15:07:27.110: D/gralloc_goldfish(732): Emulator without GPU emulation detected. 
    10-30 15:07:30.591: D/dalvikvm(732): GC_FOR_ALLOC freed 675K, 8% free 9875K/10695K, paused 33ms, total 62ms 
    10-30 15:07:30.671: D/dalvikvm(732): GC_FOR_ALLOC freed 519K, 9% free 9806K/10695K, paused 30ms, total 31ms 
    10-30 15:07:30.740: D/dalvikvm(732): GC_FOR_ALLOC freed 310K, 10% free 9713K/10695K, paused 28ms, total 29ms 
    10-30 15:07:30.751: I/dalvikvm-heap(732): Grow heap (frag case) to 10.488MB for 1000016-byte allocation 
    10-30 15:07:30.820: D/dalvikvm(732): GC_CONCURRENT freed <1K, 9% free 10690K/11719K, paused 25ms+5ms, total 74ms 
    10-30 15:07:30.911: D/dalvikvm(732): GC_FOR_ALLOC freed 0K, 9% free 10690K/11719K, paused 36ms, total 36ms 
    10-30 15:07:30.931: I/dalvikvm-heap(732): Grow heap (frag case) to 12.633MB for 2250016-byte allocation 
    10-30 15:07:31.030: D/dalvikvm(732): GC_CONCURRENT freed 0K, 8% free 12887K/13959K, paused 32ms+16ms, total 93ms 
    10-30 15:07:31.211: D/dalvikvm(732): GC_FOR_ALLOC freed 3683K, 30% free 10314K/14599K, paused 35ms, total 38ms 
    10-30 15:07:31.211: I/dalvikvm-heap(732): Grow heap (frag case) to 11.439MB for 1382416-byte allocation 
    10-30 15:07:31.360: D/dalvikvm(732): GC_CONCURRENT freed <1K, 21% free 11663K/14599K, paused 81ms+5ms, total 144ms 
    10-30 15:07:31.551: D/dalvikvm(732): GC_FOR_ALLOC freed 2555K, 32% free 9936K/14599K, paused 32ms, total 38ms 
    10-30 15:07:31.561: I/dalvikvm-heap(732): Grow heap (frag case) to 10.706MB for 1000016-byte allocation 
    10-30 15:07:31.701: D/dalvikvm(732): GC_CONCURRENT freed 1K, 26% free 10912K/14599K, paused 78ms+16ms, total 139ms 
    10-30 15:07:31.770: D/dalvikvm(732): GC_FOR_ALLOC freed 0K, 26% free 10912K/14599K, paused 31ms, total 31ms 
    10-30 15:07:31.770: I/dalvikvm-heap(732): Grow heap (frag case) to 12.850MB for 2250016-byte allocation 
    10-30 15:07:31.871: D/dalvikvm(732): GC_CONCURRENT freed 0K, 11% free 13109K/14599K, paused 29ms+6ms, total 91ms 
    10-30 15:07:32.060: D/dalvikvm(732): GC_FOR_ALLOC freed 1134K, 11% free 13102K/14599K, paused 35ms, total 39ms 
    10-30 15:07:32.070: I/dalvikvm-heap(732): Grow heap (frag case) to 14.162MB for 1382416-byte allocation 
    10-30 15:07:32.150: D/dalvikvm(732): GC_FOR_ALLOC freed <1K, 10% free 14451K/16007K, paused 36ms, total 36ms 
    10-30 15:07:32.161: I/Choreographer(732): Skipped 460 frames! The application may be doing too much work on its main thread. 
    10-30 15:07:35.280: D/AndroidRuntime(732): Shutting down VM 
    10-30 15:07:35.280: W/dalvikvm(732): threadid=1: thread exiting with uncaught exception (group=0x40a13300) 
    10-30 15:07:35.341: E/AndroidRuntime(732): FATAL EXCEPTION: main 
    10-30 15:07:35.341: E/AndroidRuntime(732): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.erachnida.restaurant.versionoct/com.erachnida.restaurant.versionoct.CustomizedListView}: android.os.NetworkOnMainThreadException 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.ActivityThread.startActivityNow(ActivityThread.java:1900) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:135) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:347) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:694) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.widget.TabHost.setCurrentTab(TabHost.java:358) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:150) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:546) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.view.View.performClick(View.java:4084) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.view.View$PerformClick.run(View.java:16966) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.os.Handler.handleCallback(Handler.java:615) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.os.Handler.dispatchMessage(Handler.java:92) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.os.Looper.loop(Looper.java:137) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.ActivityThread.main(ActivityThread.java:4745) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at java.lang.reflect.Method.invokeNative(Native Method) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at java.lang.reflect.Method.invoke(Method.java:511) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at dalvik.system.NativeStart.main(Native Method) 
    10-30 15:07:35.341: E/AndroidRuntime(732): Caused by: android.os.NetworkOnMainThreadException 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1117) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at java.net.InetAddress.lookupHostByName(InetAddress.java:385) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at java.net.InetAddress.getAllByName(InetAddress.java:214) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at com.erachnida.restaurant.versionoct.XMLParser.getXmlFromUrl(XMLParser.java:45) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at com.erachnida.restaurant.versionoct.CustomizedListView.onCreate(CustomizedListView.java:42) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.Activity.performCreate(Activity.java:5008) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079) 
    10-30 15:07:35.341: E/AndroidRuntime(732): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023) 
    10-30 15:07:35.341: E/AndroidRuntime(732): ... 18 more 
    10-30 15:07:42.250: I/Process(732): Sending signal. PID: 732 SIG: 9 

Answer 1

Esistono due soluzioni di questo problema.

1) Non scrivere una chiamata di rete in Thread UI principale, utilizzare Attività Async per quello.

2) Scrivere sotto il codice nel file MainActivity dopo setContentView (R.layout.activity_main);

if (android.os.Build.VERSION.SDK_INT > 9) { 
    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build(); 
    StrictMode.setThreadPolicy(policy); 
} 

E sotto istruzione di importazione nel file java.

import android.os.StrictMode;