Horizontal form elements

Question

I have described the form, but every element there is located under the previous one. I need to describe the form where all elements will be placed horizontally but not vertically. This is my form:

function contact_register_form($form, &$form_state) {
  $form['description'] = array(
    '#type' => 'item',
    '#title' => t('Sign up to be notified when your community launches:'),
  );

  $form['email'] = array(
    '#type' => 'textfield',
    '#title' => t('Email'),
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Add me',
  );    

  return $form;
}

Answer 1

You can use code similar to the following one, used by the Node module in node_filter_form().

  // Build the 'Update options' form.
  $form['options'] = array(
    '#type' => 'fieldset', 
    '#title' => t('Update options'), 
    '#attributes' => array('class' => array('container-inline')), 
    '#access' => $admin_access,
  );

  // ...

  $form['options']['operation'] = array(
    '#type' => 'select', 
    '#title' => t('Operation'), 
    '#title_display' => 'invisible', 
    '#options' => $options, 
    '#default_value' => 'approve',
  );

The key is the line settings the "#attributes" attribute to "container-inline."

That code is for Drupal 7; the equivalent code for Drupal 6 starts with the following code:

  $form['options'] = array(
    '#type' => 'fieldset', 
    '#title' => t('Update options'), 
    '#prefix' => '<div class="container-inline">', 
    '#suffix' => '</div>',
  );

Supposing you are using Drupal 6, then your code should be changed to something similar to the following one:

function contact_register_form($form, &$form_state) {
  $form['description'] = array(
    '#type' => 'item',
    '#title' => t('Sign up to be notified when your community launches:'),
  );

  $form['email'] = array(
    '#type' => 'textfield',
    '#title' => t('Email'),
    '#prefix' => '<div class="container-inline">', 
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => 'Add me',
    '#suffix' => '</div>',
  );    

  return $form;
}

I didn't put the description inline, as it would not be correctly rendered because it is using a "item" form field. I also find that inlining the description would cause the form to take too much space. (Imagine what would happen if the inlined description would be longer, and placed in a single line.)

The CSS styles that Drupal 7 adds to container-inline elements are the following.

/**
 * Inline items.
 */
.container-inline div,
.container-inline label {
  display: inline;
}
/* Fieldset contents always need to be rendered as block. */
.container-inline .fieldset-wrapper {
  display: block;
}

They are added from system.base.css.