What is wrong in my android app with HttpPost?

Question

I'm making a new android app, when I send a values with HttpPost to my web file post.php, but it is don't working. What is it wrong ?

activity_activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context=".ActivityPrincipal">

</RelativeLayout>

ActivityPrincipal.java

package com.pixelayer.httppost.httppostandroid;

import java.io.IOException;
import java.io.UnsupportedEncodingException;
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.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;

import android.util.Log;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;


public class ActivityPrincipal extends ActionBarActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_activity_principal);

    HttpClient httpClient = new DefaultHttpClient();

    HttpPost httpPost = new HttpPost("www.mysite.com/post.php"); //
    replace with
    // your url

    List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(2);

    nameValuePair.add(new BasicNameValuePair("nome", "test_user"));

    nameValuePair.add(new BasicNameValuePair("site", "testeandroid"));

    // Encoding data

    try {
        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
    } catch (UnsupportedEncodingException e) {
        // log exception
        e.printStackTrace();
    }

    // making request

    try {
        HttpResponse response = httpClient.execute(httpPost);
        // write response to log
        Log.d("Http Post Response:", response.toString());
    } catch (ClientProtocolException e) {
        // Log exception
        e.printStackTrace();
    } catch (IOException e) {
        // Log exception
        e.printStackTrace();
    }

}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_activity_principal, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.pixelayer.httppost.httppostandroid" >

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

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".ActivityPrincipal"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

</manifest>

Thank you so much

Answer 1

My new ActivityPrincipal.java

It is code is correct now ?

package com.pixelayer.httppost.httppostandroid;

import android.os.AsyncTask;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.util.EntityUtils;


public class ActivityPrincipal extends ActionBarActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_activity_principal);

    TextView t = (TextView)findViewById(R.id.textViewPost);
    new TheTask().execute("mysite.com/post.php");
}

class TheTask extends AsyncTask<String,Void,String>
{

    @Override
    protected String doInBackground(String... arg0) {
        String text =null;
        try {
            HttpClient httpclient = new DefaultHttpClient();
            HttpPost httppost = new HttpPost(arg0[0]);
            HttpResponse resp = httpclient.execute(httppost);
            HttpEntity ent = resp.getEntity();
            text = EntityUtils.toString(ent);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }

        return text;
    }

    @Override
    protected void onPostExecute(String result) {
        // TODO Auto-generated method stub
        super.onPostExecute(result);
        TextView t = (TextView)findViewById(R.id.textViewPost);
        t.setText(result);
    }

}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_activity_principal, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}
}

Answer 2

You are doing this HTTP request in main thread, if you look your logcat you can see that it's not allowed.

You should use the AsyncTask to do it or a library (like Volley or Loopj).

To force Android to performe this you must change the StrictMode policy (insert this code before HTTP request)

StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
 StrictMode.setThreadPolicy(policy);

AsyncTask example

private class HTTPTask extends AsyncTask<String, Void, String> {
    @Override
    protected String doInBackground(String... urls) {
      String response = "";
      ...Performe your request
      return response;
    }

@Override
protected void onPostExecute(String result) {
  .../Use response
}

}

To call...

HTTPTask task = new HTTPTask();
task.execute(new String[] { "http://www.url.com" });

For Loopj there is a Doc http://loopj.com/android-async-http/ For Volley https://developer.android.com/training/volley/index.html