当我在模拟器上测试时,它可以正常工作,但是在使用我的设备(galaxy s3)进行测试时,它会在以下代码中出现错误:
HttpResponse response;
response = httpclient.execute(httppost);
例外:
09-03 08:16:49.018: E/AndroidRuntime(24254): java.lang.RuntimeException: Unable to start activity ComponentInfo{sg.dianping/sg.dianping.activity.ItemListActivity}: android.os.NetworkOnMainThreadException
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1970)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1995)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.app.ActivityThread.access$600(ActivityThread.java:128)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1161)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.os.Handler.dispatchMessage(Handler.java:99)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.os.Looper.loop(Looper.java:137)
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.app.ActivityThread.main(ActivityThread.java:4517)
09-03 08:16:49.018: E/AndroidRuntime(24254): at java.lang.reflect.Method.invokeNative(Native Method)
09-03 08:16:49.018: E/AndroidRuntime(24254): at java.lang.reflect.Method.invoke(Method.java:511)
09-03 08:16:49.018: E/AndroidRuntime(24254): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:993)
09-03 08:16:49.018: E/AndroidRuntime(24254): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:760)
09-03 08:16:49.018: E/AndroidRuntime(24254): at dalvik.system.NativeStart.main(Native Method)
09-03 08:16:49.018: E/AndroidRuntime(24254): Caused by: android.os.NetworkOnMainThreadException
09-03 08:16:49.018: E/AndroidRuntime(24254): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
09-03 08:16:49.018: E/AndroidRuntime(24254): at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
答案 0 :(得分:15)
当您在UI线程上执行网络活动时,抛出此异常NetworkingOnMainThread
。它有可能阻塞主线程,因为它会在恢复之前等待网络连接完成,从而阻塞线程。
您有2个选项。
1 - 将所有网络移动到其他线程。最常见且最简单的解决方案是AsyncTask 但还有其他选项,例如Handlers。这是推荐的选项。
2-您可以更改策略以允许在UI线程上进行联网。
只需添加此代码
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
不建议使用此选项,因为它只是绕过了异常。抛出异常是有原因的。我会选择第一个选项。有很多关于如何实现AsyncTask
的教程。