How does a form call itself on submit in Drupal - drupal-7

Question

I am creating a custom module that I would like to use to display a form, from a module. The form queries a database and displays some information. The database connection is working, and the data has been retrieved successfully. The form has also been displayed successfully, but what I can figure out is how to link all together to have the page displayed again when submitting the form. My code is:
<?php
function menu($may_cache) {
$items = array();
$items['admin/reporting/report_details'] = array(
'title' => 'Report: User details by stores',
'access arguments' => array('access content'),
'page callback' => 'say_report_details',
'type' => MENU_CALLBACK,
);
return $items;
}
// This function should execute the logic if the $_GET variable is set
function say_report_details($values = array()) {
// The $_GET logic will be somtehing like this
// if (count($_GET) > 0)
// Get all the form values from the $_GET wit something like:
// if (count($_GET) > 0) {
// $start = mktime(0, 0, 0, $_GET['from_month'], $_GET['from_day'],
$_GET['from_year']);
// $end = mktime(23, 59, 59, $_GET['to_month'], $_GET['to_day'], $_GET['to_year']);
if ($_GET['store'] > 0) {
$form = drupal_get_form("report_details_form");
$output = theme("report_page", $form, $output);
return $output;
}
function report_details_form() {
$form["search"] = array(
'#type' => 'fieldset',
'#title' => t('Search params'),
'#collapsible' => FALSE,
'#tree' => TRUE,
);
for ($i = 1; $i < 32; $i++) {
$days_opt[$i] = $i;
}
for ($i = 1; $i < 13; $i++) {
$month_opt[$i] = $i;
}
for ($i = 2008; $i < date("Y") + 3; $i++) {
$year_opt[$i] = $i;
}
$form["search"]["from_day"] = array(
'#type' => 'select',
'#title' => 'Date from',
'#options' => $days_opt,
'#default_value' => (($_GET['from_day'] == "") ? date("d") : $_GET['from_day'])
);
$form["search"]["from_month"] = array(
'#type' => 'select',
'#title' => ' ',
'#options' => $month_opt,
'#default_value' => (($_GET['from_month'] == "") ? date("m") : $_GET['from_month'])
);
$form["search"]["from_year"] = array(
'#type' => 'select',
'#title' => ' ',
'#options' => $year_opt,
'#default_value' => (($_GET['from_year'] == "") ? date("Y") : $_GET['from_year'])
);
$form["search"]["to_day"] = array(
'#type' => 'select',
'#title' => 'Date to',
'#options' => $days_opt,
'#default_value' => (($_GET['to_day'] == "") ? date("d") : $_GET['to_day'])
);
$form["search"]["to_month"] = array(
'#type' => 'select',
'#title' => ' ',
'#options' => $month_opt,
'#default_value' => (($_GET['to_month'] == "") ? date("m") : $_GET['to_month'])
);
$form["search"]["to_year"] = array(
'#type' => 'select',
'#title' => ' ',
'#options' => $year_opt,
'#default_value' => (($_GET['to_year'] == "") ? date("Y") : $_GET['to_year'])
);
$result = db_query('SELECT taxonomy_term_data.name, taxonomy_term_data.tid FROM
taxonomy_term_data WHERE vid = 10');
$strs = array("all" => "All");
foreach ($result as $store) {
$strs[$store->tid] = $store->name;
}
$form["search"]["store"] = array(
'#type' => 'select',
'#title' => 'Stores',
'#options' => $strs,
'#default_value' => $_GET['store']
);
$form["submit"] = array("#type" => "submit", "#value" => "Show report");
return $form;
}
function theme_report_page($form, $result = array()) {
$output = '
<div id="report_form">
'. $form .'
</div>
<div id="report_result">
'. $result .'
</div>
';
return $output;
}
function theme_report_details_form($form) {
unset($form['search']['from_day']['#title']);
unset($form['search']['from_month']['#title']);
unset($form['search']['from_year']['#title']);
unset($form['search']['to_day']['#title']);
unset($form['search']['to_month']['#title']);
unset($form['search']['to_year']['#title']);
unset($form['search']['store']['#title']);
$output = "<fieldset>
<legend>Search params</legend>
<div class='fieldtitles'>". t('Date From') .":</div>
". drupal_render($form['search']['from_day']) ."
". drupal_render($form['search']['from_month']) ."
". drupal_render($form['search']['from_year']) ."
<div class='clearing'> </div>
<div class='fieldtitles'>". t('Date To') .":</div>
". drupal_render($form['search']['to_day']) ."
". drupal_render($form['search']['to_month']) ."
". drupal_render($form['search']['to_year']) ."
<div class='clearing'> </div>
<div class='fieldtitles'>". t('Store') .":</div>
". drupal_render($form['search']['store']) ."
<div class='clearing'> </div>
". drupal_render($form['submit']) ."
</fieldset>";
unset($form['search']);
$output .= drupal_render($form);
return $output;
}
function report_details_form_submit($form_id, $form_values) {
$query = "";
// This next line is the one we are having an issue right now, as is trowing an
error due to $form_values is empty for some UNKNOWN reason...
foreach ($form_values['search'] as $key => $value) {
$query .= "&". $key ."=". $value;
}
return array('admin/reporting/report_details', $query);
}

Answer 1

I did not look over all the details of the form, but the submit function for D7 should look like this:
function my_module_example_form_submit($form, &$form_state) {
// do something
}
I think that should fix the problem. If not check out this link: http://api.drupal.org/api/drupal/includes%21form.inc/group/form_api/7

Answer 2

Please read & follow the answer mikewink provided.
In addition in the three working forms that I've created the menu item array is as follows:
$items = array();
$items['admin/config/system/dataforms/SiteAccessform']=array(
'title'=>'Site Access' //this should be watever the Title of your form is
,'description'=>'Configuration for the Data Forms module' //shows up by your menu item as it's description (where applicable)
,'page callback'=>'drupal_get_form' //this, as I understand it, is required for forms to work properly (& may be part of the cause of your problems)
,'page arguments'=>array('dataforms_main_form') //IMPORTANT this is the actual name of your function that will be executed to produce the form
,'access arguments'=>array('administer settings for dataforms') //??
,'type'=>MENU_CALLBACK//these work when the path is accessed though no menu items are created
,
);
A few more points, when you are on a particular 'menu' item with it's page arguments array element set to your form, it considers it ONE form only. That is to say that the one function will be the only function that will be able to create a form (in my experience). Therefore use logic in that function to produce different forms if applicable... ,(as opposed to attempting to have a button that calls another function... which did not work for me).
Also, again referring back to mikewink's answer, the $form_state variable is the method of storing state that you want to pay attention, & not the standard $_GET or $_POST variables.
This link might be mildly helpful: https://api.drupal.org/api/drupal/developer!topics!forms_api_reference.html/7
However I gleaned the most valuable information from the examples module: https://drupal.org/project/examples
Good Luck!