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Android

Posted by Lean Karlo Corpuz
Lean Karlo Corpuz
6,159 Points

httpResponse = httpClient.execute(httpGet); crashes the app

app keeps on crashing Here is my code

import android.app.Activity;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import java.io.IOException;

/**
 * Created by Lean Karlo Corpuz on 5/2/14.
 */
public class PostActivity extends Activity {

    static String response = null;

    public void loadPost() throws IOException {
        DefaultHttpClient httpClient = new DefaultHttpClient();
        HttpEntity httpEntity = null;
        HttpResponse httpResponse = null;

        String blogFeedUrl = "http://localhost/medapp/public/mobile/post";

        HttpGet httpGet = new HttpGet(blogFeedUrl);
        httpResponse = httpClient.execute(httpGet); // the part where the application crashes

    }

}

here is the log

05-02 10:22:13.514 2819-2819/medapp.app E/AndroidRuntime? FATAL EXCEPTION: main Process: medapp.app, PID: 2819 android.os.NetworkOnMainThreadException at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1145) at java.net.InetAddress.lookupHostByName(InetAddress.java:385) at java.net.InetAddress.getAllByNameImpl(InetAddress.java:236) at java.net.InetAddress.getAllByName(InetAddress.java:214) at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:137) at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164) at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119) at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360) at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555) at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487) at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465) at medapp.app.PostActivity.loadPost(PostActivity.java:27) at medapp.app.ActionFragment.onCreateView(ActionFragment.java:38) at android.app.Fragment.performCreateView(Fragment.java:1700) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:890) at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1062) at android.app.BackStackRecord.run(BackStackRecord.java:684) at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1447) at android.app.FragmentManagerImpl$1.run(FragmentManager.java:443) at android.os.Handler.handleCallback(Handler.java:733) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:136) at android.app.ActivityThread.main(ActivityThread.java:5017) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:515) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) at dalvik.system.NativeStart.main(Native Method)

1 Answer

Ben Jakuben
STAFF
Ben Jakuben
Treehouse Teacher
Ben Jakuben
Ben Jakuben
Treehouse Teacher

Hi Lean, you are receiving the NetworkOnMainThreadException which pretty literally describes the problem. In Android, we aren't allowed to perform network operations on the main thread of our applications. We talk about this in the video Requesting Data from the Web the Wrong Way. I'd suggest working through that and the subsequent videos to see how to make a network call using a background thread known as an AsyncTask.

Alternatively, you could look into a library like Retrofit, which I really like. I want to cover some libraries like this in a workshop.