Can't invoke URL on Android

Question

I'm a noob at Java & PHP, I don't understand how this doesn't work. What I want to do is when I press a button in my Android app I want this PHP script to be executed:

<?php

    mysql_connect("x","x","x"); // host, username, password...
    mysql_select_db("x"); // db name...

    $id=$_GET["id"];
    $status=$_GET["status"];

    mysql_query("UPDATE list SET status = $status WHERE id = $id");

    mysql_close();

?>

and this is what is supposed to trigger it:

public void insertDataToDB(int id, int status) {
    try {
        HttpGet httpget = new HttpGet("http://10.0.2.2/SetStatus.php?id=" + id + "&status=" + status);
        Log.d("link", "http://10.0.2.2/SetStatus.php?id=" + id + "&status=" + status);
        httpclient.execute(httpget);

    } catch (Exception e) {
        Log.e("insertDataToDB", "ERROR : " + e.getMessage());
    }
}

This is my error message:

23:40:51.270: insertDataToDB(1914): ERROR : null

I've tried using both HttpGet and HttpPost as well as _GET and _POST in the php script, but nothing seems to work so I just stuck with _GET as the script works when i write the link into my browser. I need help, thanks in advance! :)

(it does not make any difference if i cast id & status to strings nor if i set them to constant values.)

UPDATE

Error log:

11-15 00:05:57.700: E/insertDataToDB(2080): android.os.NetworkOnMainThreadException
11-15 00:05:57.700: E/insertDataToDB(2080):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
11-15 00:05:57.700: E/insertDataToDB(2080):     at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:110)
11-15 00:05:57.700: E/insertDataToDB(2080):     at libcore.io.IoBridge.connectErrno(IoBridge.java:137)
11-15 00:05:57.700: E/insertDataToDB(2080):     at libcore.io.IoBridge.connect(IoBridge.java:122)
11-15 00:05:57.700: E/insertDataToDB(2080):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:183)
11-15 00:05:57.700: E/insertDataToDB(2080):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:456)
11-15 00:05:57.700: E/insertDataToDB(2080):     at java.net.Socket.connect(Socket.java:882)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:119)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:360)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:555)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:487)
11-15 00:05:57.700: E/insertDataToDB(2080):     at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:465)
11-15 00:05:57.700: E/insertDataToDB(2080):     at com.example.fibergruppenlista.DataBase.insertDataToDB(DataBase.java:34)
11-15 00:05:57.700: E/insertDataToDB(2080):     at com.example.fibergruppenlista.ListClickListener$2.onClick(ListClickListener.java:47)
11-15 00:05:57.700: E/insertDataToDB(2080):     at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:160)
11-15 00:05:57.700: E/insertDataToDB(2080):     at android.os.Handler.dispatchMessage(Handler.java:102)
11-15 00:05:57.700: E/insertDataToDB(2080):     at android.os.Looper.loop(Looper.java:135)
11-15 00:05:57.700: E/insertDataToDB(2080):     at android.app.ActivityThread.main(ActivityThread.java:5221)
11-15 00:05:57.700: E/insertDataToDB(2080):     at java.lang.reflect.Method.invoke(Native Method)
11-15 00:05:57.700: E/insertDataToDB(2080):     at java.lang.reflect.Method.invoke(Method.java:372)
11-15 00:05:57.700: E/insertDataToDB(2080):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
11-15 00:05:57.700: E/insertDataToDB(2080):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)

I tried using an asynctask<void, void, void> but I can't get it to work, the insertDataToDB method is by the way not located inside of the MainActivity.java class.

What do you see if you change `Log.e("insertDataToDB", "ERROR : " + e.getMessage());` to `Log.e("insertDataToDB", "ERROR : " + e.getMessage(), e);`? — BackSlash, Nov 14 '14 at 23:01
@isim it's in the class like this: private HttpClient httpclient = new DefaultHttpClient(); — fralexxelarf, Nov 14 '14 at 23:08
possible duplicate of [android.os.NetworkOnMainThreadException](http://stackoverflow.com/questions/6343166/android-os-networkonmainthreadexception) — BackSlash, Nov 14 '14 at 23:11

score 1 · Answer 1 · edited May 23 '17 at 12:05

1

This is not related to Java or PHP. On Android, you cannot perform network operations in the main thread (the UI thread). I suggest you to run your code in an AsyncTask for instance. See this answer with an example code.

Look at the official Android NetworkOnMainThreadException documentation and at this guide to keep your app responsive.

edited May 23 '17 at 12:05

Community

1
1

answered Nov 14 '14 at 23:23

metch

673
7
14

I have another method which returns info from my database and it works fine, are you sure i need an asynctask? thanks. – fralexxelarf Nov 15 '14 at 00:37
Your method `insertDataToDB` is called from the main Thread in which you cannot perform any network operations (`NetworkOnMainThreadException`). Using an `AsyncTask` is the easiest way to solve your issue. – metch Nov 15 '14 at 13:51

Can't invoke URL on Android

1 Answers1