Combining a website with android - php

Question

I am trying to make a register app using Eclipse. I want the user to be able to fill in information in the app and click a button that will send the information to a PHP website.
However, it seems that when I click the button it doesn't send the information (display name, username and password) to the website.
Here are the lines of code of the app:
public class MainActivity extends ActionBarActivity {
EditText displayname, username, password, responseText;
String displaynameText, usernameText, passwordText;
Button registerbtn;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
displayname = (EditText) findViewById(R.id.editText1);
username = (EditText) findViewById(R.id.editText2);
password = (EditText) findViewById(R.id.editText3);
responseText = (EditText) findViewById(R.id.responseLog);
registerbtn = (Button) findViewById(R.id.button1);
displaynameText = displayname.getText().toString();
usernameText = username.getText().toString();
passwordText = password.getText().toString();
final HttpClient httpClient = new DefaultHttpClient();
final HttpPost httpPost = new HttpPost("http://anschluss.webuda.com/register.php");
final List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(3);
nameValuePair.add(new BasicNameValuePair("displayname", displaynameText));
nameValuePair.add(new BasicNameValuePair("username", usernameText));
nameValuePair.add(new BasicNameValuePair("password", passwordText));
registerbtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try{
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
} catch(UnsupportedEncodingException e){
e.printStackTrace();
}
try{
HttpResponse response = httpClient.execute(httpPost);
responseText.setText(response.toString());
} catch(Exception e){
e.printStackTrace();
}
}
});
}
As for the PHP I have this:
<?php
if(isset($_POST)){
$displayname = $_POST["displayname"];
$username = $_POST["username"];
$password = $_POST["password"];
if(!empty($displayname) && !empty($username) && !empty($password)){
$mysql_host = "hostname";
$mysql_database = "database";
$mysql_user = "username";
$mysql_password = "password";
mysql_connect($mysql_host, $mysql_user, $mysql_password);
mysql_select_db($mysql_database);
$checkDisplayName = mysql_query("SELECT displayname FROM info WHERE displayname = '$displayname'");
$displayNameAantal = mysql_num_rows($checkDisplayName);
$checkUsername = mysql_query("SELECT username FROM info WHERE username = '$username'");
$usernameAantal = mysql_num_rows($checkUsername);
if($displayNameAantal == 0){
if($usernameAantal == 0){
$insertQuery = mysql_query("INSERT INTO info(displayname, username, password) VALUES ('$displayname', ' $username', '$password')");
$returnValue = "Succes";
echo $returnValue;
} else{
$returnValue = "Username is already taken";
echo $returnValue;
}
} else{
$returnValue = "Displayname is already taken";
echo $returnValue;
}
} else{
$returnValue = "Something is left blank";
echo $returnValue;
}
}
?>
Please let me know if you know how to make this work.

Answer 1

There's something conceptually very wrong in your code: You are accessing the network inside the UI thread (=== blocking the user interface). Check if Android isn't complaining about that! Network access must be done in a thread outside the UI, using an AsyncTask (Android's preferred way) or manually spawning a Thread (classic Java way).
If there are no other errors related to the HTTP Post, probably this is what's happening. However, if you fix other possible errors and the HTTP post is sent, you will get a Called From Wrong Thread exception.

Answer 2

response.toString() is incorrect try using this to get the response:
EntityUtils.toString(response.getEntity(), "UTF-8");