Display formresults in same block as form

Question

I have created a module that writes a block with a very simple form in it.

The purpose of it is calculating distance between 2 adresses, one fixed, one asked by the form.

Now I can't get the results to show in the block itself, and I can't find any tutorials on how to do that.

The block shows, the form is in it also, but when i submit a postalcode it seems that nothing happens (also the postcode input field resets to emtpy).

the code that retrieves the distance works also (tested on commandline).

How can I approach this?

The code for my block:

  function reiskosten_block_view($delta = '') {
  $block = array();

  switch ($delta) {
  case 'reiskostenblock':
  $block['subject'] = t('Reiskosten berekenen');
  $block['content'] = drupal_get_form('reiskosten_form');
  break;
  }

The code for submitting the form:

function reiskosten_form_submit($form, &$form_state) {

/* REPLACE SPACE OR HTTP-REQUEST WILL BE MALFORMED */
  $postcode = str_replace(' ','',$form_state['values']['postcode']);

  $url = "https://maps.googleapis.com/maps/api/distancematrix/json?origins=1024AA|Netherlands&destinations=$postcode|Netherlands&mode=car&language=nl-NL&sensor=false&key=myKey";

$data = drupal_http_request($url);
$result = drupal_json_decode($data->data);

$destination = $result['destination_addresses'][0];
$distance = $result['rows'][0]['elements'][0]['distance']['text'];
$duraton = $result['rows'][0]['elements'][0]['duration']['text'];

  drupal_set_message("$distance");  
  $form_state['rebuild'] = TRUE;
}

I want the output of $result to be shown below the submitbutton. It is driving me crazy this one, been puzzling for 5 hours now on this thing (what should be relatively simple imho).

edit: I also validate on postalcode with:

function reiskosten_form_validate($form, &$form_state) {
  if ( empty($form_state['values']['postcode']) ) {
    form_set_error('postcode', t('Postcode mag niet leeg zijn'));
  }
}

It doesn't throw an error so it seems to me that 'postcode' has a value and the function should be processed.

Answer 1

Solved it. Solution:

in function reiskosten_form_submit($form, &$form_state) {

$result = drupal_json_decode($data->data);
$form_state['results'] = $result;

in function reiskosten_form($form, &$form_state) {

$form['destination'] = array(
  '#markup' => '<div>' . $form_state['results']['destination_addresses'][0] . '</div>',
);

Wrap t in an if to see if the values are there and the magic happens. Pfff