Question

I’m very inexperienced when it comes to developing Android Applications and I cannot code a lot of Java. I have been google’ing around for around 2 hours now, trying many different examples of how to send POST data to a HTTP web server page and getting the outputted data, but none work. I am using the Android SDK Version 4.0 (API 14), does anyone know how to do this? Just a simple post some data, and get the output.

Thanks.

EDIT: Here is my current code,

package me.babblebox.application;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;

public class BabbleBoxActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
    public void check_login() {
        // Create a new HttpClient and Post Header
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost("http://babblebox.me/android/test.php");

        try {
            // Add your data
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
            nameValuePairs.add(new BasicNameValuePair("id", "12345"));
            nameValuePairs.add(new BasicNameValuePair("stringdata", "Hi"));
            httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

            // Execute HTTP Post Request
            HttpResponse response = httpclient.execute(httppost);

        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
        } catch (IOException e) {
            // TODO Auto-generated catch block
        }
    }
    public void check_login_button(View v) {
           check_login();
    }
}

manifest file:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="me.babblebox.application"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="14" /><application android:icon="@drawable/bb_launch_icon" android:label="@string/app_name" android:testOnly="false" android:name=".BabbleBox" android:enabled="true">
        <activity android:label="@string/app_name" android:name=".BabbleBoxActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
    <uses-permission android:name="android.permission.INTERNET" />

</manifest>

Button XML that calls the method:

<Button
        android:id="@+id/Button_Login"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Login"
        android:onClick="check_login_button"/>

Answer 1

public void postData() {
    // Create a new HttpClient and Post Header
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost("http://www.yoursite.com/script.php");

    try {
        // Add your data
        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
        nameValuePairs.add(new BasicNameValuePair("id", "12345"));
        nameValuePairs.add(new BasicNameValuePair("stringdata", "Hi"));
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

        // Execute HTTP Post Request
        HttpResponse response = httpclient.execute(httppost);

    } catch (ClientProtocolException e) {
        // TODO Auto-generated catch block
    } catch (IOException e) {
        // TODO Auto-generated catch block
    }
} 

Also you must add permissions to ApplicationManifest.xml to allow internet:

<manifest xlmns:android...>
 ...
 <uses-permission android:name="android.permission.INTERNET"></uses-permission>
</manifest>

EDIT:

Your problem is not in the POST code, but how you are calling the onClick method, try this to fix your problem:

public void buttonListener(View v) {
   check_login();
}

And call make your layout XML look similar to this:

<Button 
   android:text="Calling From XML Layout"
   android:id="@+id/Button04" android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:onClick="buttonListener">
</Button>

You must add one parameter to Listener method that is the View.