Android Send Post Data To Server

Android Send Post Data To Server

This is a possible duplicate of Sending POST data in Android
I used this code to send post data to server using android
public void postData() {
// Create a new HttpClient and Post Header
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new
HttpPost("http://www.mysite.com/android.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
}
}
But when I run this app it shows this error
java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.example.senddata/com.example.senddata.MainActivity}:
android.os.NetworkOnMainThreadException
Whats problem? Can anyone help?