Update old android project

Question

I am following this tutorial and I can make it work just fine, but when I try to update the UI to fit the new Holo.Light in android 4.2 the app crashes at launch, and I don't know why.

I have been searching for a way to update the UI but I could not get it to work.

I wonder if anybody could help me? tell me how? Give me a link that you know would work? or even do it yourself?

i get this error log:

11-20 09:50:39.523: I/dalvikvm(1460): threadid=3: reacting to signal 3
11-20 09:50:39.682: I/dalvikvm(1460): Wrote stack traces to '/data/anr/traces.txt'
11-20 09:50:39.892: I/dalvikvm(1460): threadid=3: reacting to signal 3
11-20 09:50:40.003: I/dalvikvm(1460): Wrote stack traces to '/data/anr/traces.txt'
11-20 09:50:40.102: D/AndroidRuntime(1460): Shutting down VM
11-20 09:50:40.102: W/dalvikvm(1460): threadid=1: thread exiting with uncaught exception (group=0x409c01f8)
11-20 09:50:40.132: E/AndroidRuntime(1460): FATAL EXCEPTION: main
11-20 09:50:40.132: E/AndroidRuntime(1460): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.androidhive.jsonparsing/com.androidhive.jsonparsing.AndroidJSONParsingActivity}: android.os.NetworkOnMainThreadException
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread.access$600(ActivityThread.java:123)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.os.Looper.loop(Looper.java:137)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread.main(ActivityThread.java:4424)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at java.lang.reflect.Method.invokeNative(Native Method)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at java.lang.reflect.Method.invoke(Method.java:511)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at dalvik.system.NativeStart.main(Native Method)
11-20 09:50:40.132: E/AndroidRuntime(1460): Caused by: android.os.NetworkOnMainThreadException
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1099)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at com.androidhive.jsonparsing.JSONParser.getJSONFromUrl(JSONParser.java:38)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at com.androidhive.jsonparsing.AndroidJSONParsingActivity.onCreate(AndroidJSONParsingActivity.java:53)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.Activity.performCreate(Activity.java:4465)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
11-20 09:50:40.132: E/AndroidRuntime(1460):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
11-20 09:50:40.132: E/AndroidRuntime(1460):     ... 11 more
11-20 09:50:40.392: I/dalvikvm(1460): threadid=3: reacting to signal 3
11-20 09:50:40.412: I/dalvikvm(1460): Wrote stack traces to '/data/anr/traces.txt'
11-20 09:50:40.791: I/dalvikvm(1460): threadid=3: reacting to signal 3
11-20 09:50:40.962: I/dalvikvm(1460): Wrote stack traces to '/data/anr/traces.txt'

Answer 1

You are making a network call on the main thread. This is not allowed on Android 4.2, and is a really bad idea on earlier versions which do permit this. I have blogged about various mechanisms for moving network and other heavy calls off the main thread at http://blog.stylingandroid.com/archives/833.

Without seeing your code, I cannot begin to suggest which approach is the right one for you to use, but hopefully the information in my articles will help you in deciding upon the correct approach.