باگ در پروژه Note

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متن کرش : 

02-03 14:11:06.123: D/AndroidRuntime(1403): Shutting down VM
02-03 14:11:06.131: E/AndroidRuntime(1403): FATAL EXCEPTION: main
02-03 14:11:06.131: E/AndroidRuntime(1403): Process: com.uncocoder.course.app.notes, PID: 1403
02-03 14:11:06.131: E/AndroidRuntime(1403): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.uncocoder.course.app.notes/com.uncocoder.course.app.notes.ActivityMain}: android.os.NetworkOnMainThreadException
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread.access$800(ActivityThread.java:144)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.os.Handler.dispatchMessage(Handler.java:102)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.os.Looper.loop(Looper.java:135)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread.main(ActivityThread.java:5221)
02-03 14:11:06.131: E/AndroidRuntime(1403): at java.lang.reflect.Method.invoke(Native Method)
02-03 14:11:06.131: E/AndroidRuntime(1403): at java.lang.reflect.Method.invoke(Method.java:372)
02-03 14:11:06.131: E/AndroidRuntime(1403): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
02-03 14:11:06.131: E/AndroidRuntime(1403): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
02-03 14:11:06.131: E/AndroidRuntime(1403): Caused by: android.os.NetworkOnMainThreadException
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
02-03 14:11:06.131: E/AndroidRuntime(1403): at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:110)
02-03 14:11:06.131: E/AndroidRuntime(1403): at libcore.io.IoBridge.connectErrno(IoBridge.java:137)
02-03 14:11:06.131: E/AndroidRuntime(1403): at libcore.io.IoBridge.connect(IoBridge.java:122)
02-03 14:11:06.131: E/AndroidRuntime(1403): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:183)
02-03 14:11:06.131: E/AndroidRuntime(1403): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:456)
02-03 14:11:06.131: E/AndroidRuntime(1403): at java.net.Socket.connect(Socket.java:882)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
02-03 14:11:06.131: E/AndroidRuntime(1403): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
02-03 14:11:06.131: E/AndroidRuntime(1403): at com.uncocoder.course.app.notes.Webservice.readUrl(Webservice.java:25)
02-03 14:11:06.131: E/AndroidRuntime(1403): at com.uncocoder.course.app.notes.ActivityMain.sendData(ActivityMain.java:30)
02-03 14:11:06.131: E/AndroidRuntime(1403): at com.uncocoder.course.app.notes.ActivityMain.onCreate(ActivityMain.java:23)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.Activity.performCreate(Activity.java:5933)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
02-03 14:11:06.131: E/AndroidRuntime(1403): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
02-03 14:11:06.131: E/AndroidRuntime(1403): ... 10 more

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