Why can't I save a value from my form?

Question

I have a problem with my module that only creates a form to submit a validation. The target of this module is to set a variable that I put in a textfield. The problem is that it doesn't save the variable, it only shows the default value. (I use variable_set and variable_get)

This variable is necessary because I use this form in another module that get this variable from the database. (My variable is id_event)

This is my code of my own module:

<?php
function example_form_form1(){
    $form['id_event'] = array(
     '#type' => 'textfield',
     '#title' => t('Id Event'),
     '#required' => TRUE,
         '#value' => variable_get('id_event', 7), //Here is my dude
    );

    $form['submit'] = array(
     '#type' => 'submit',
     '#value' => t('enviar'),
    );
 return $form;
}

function example_form_submit($form, $form_state){
    $id_event = $form_state['values']['id_event'];
        variable_set('id_event', $id_event);//here is my dude
        drupal_set_message($id_event);
}
?>

Now, this variable is necesary for other module that only get.

<?php
$file_json = $this->options['xml_file'].variable_get('id_event', 1);
//Here don't get the value that i put, only put the value for default.
?>

Thanks :D

Answer 1

There are a few problems I see.

1. The submit function in this example doesn't follow the same naming
   convention as your form constructor.
2. You are also setting the #value of the id_event form element when you probably want to be setting the #default_value (a #value cannot be changed by the user).
3. Your functions are missing their default arguments, which doesn't necessarily mean they will break but is bar form.

Try this:

<?php

function example_form_form1($form, &$form_state) {
  $form['id_event'] = array(
    '#type' => 'textfield',
    '#title' => t('Id Event'),
    '#required' => TRUE,
    '#default_value' => variable_get('id_event', 7),
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('enviar'),
  );
  return $form;
}

function example_form_form1_submit(&$form, &$form_state) {
  variable_set('id_event', $form_state['values']['id_event']);
  drupal_set_message($id_event);
}
?>

Answer 2

The reason your current code isn't working is because your submit handler doesn't follow the correct naming convention (i.e. FORM_FUNCTION_NAME_submit) and you don't explicitly attach the submit handler to the form anywhere so it's not being run.

You can solve this by simply changing the nameof your submit handler:

function example_form_form1_submit($form, $form_state){

Or you could look at system_settings_form() which automates much of this process for you.