how to create custom block with dropdown list in drupal?

Question

i want to create a custom block for dropdown list which i can display in all pages.

/*
 *implements hook_menu().
 */

function dropdown_page_menu(){
  $items = array();
  $items['page/layout/%'] = array(
    'title' => 'Select Layout',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dropdown_page_select_form'),
    'access arguments' => array('access content'),
    );

  return $items;
}

/**
 * Implements hook_theme().
 */

function dropdown_page_theme(){
    return array(
      'dropdown_page_select_form' => array('render element' => 'form',),
      );
}




function dropdown_page_page(){
  $content[] = l(t('select layout'),'page/layout/%');

  return $content;
}

function dropdown_page_select_form($form, &$form_state){
  $options = array(
    'select' => t('Select'),
    'layout_1' => t('Layout 1'),
    'layout_2' => t('Layout 2'),
    'layout_3' => t('Layout 3'),
    );

  $form['choice'] = array(
    '#type' => 'select',
    '#options' => $options,
    '#title' => t('Select your layout'),
    );
  dsm($options);
  $form['submit'] = array(
    '#type' => 'submit',
    '#value'=> t('Go'),
    );
  return $form;
}

function dropdown_page_select_form_submit($form, &$form_state){


switch ($form_state['values']['choice']) {
  case layout_1: {

    //echo 'hi';die;
    drupal_goto("layout_1".$options);
    break;


  }
  case layout_2: {  
    //echo 'no';die;
    drupal_goto("layout_2".$options);
    break;
  }
  case layout_3: {  
    drupal_goto("layout_3".$options);
    break;
  }
  default: {
    print 'Select it!';
  }
}



  drupal_set_message(t('Your layout %input', array('%input' => $form_state['value']['choice'])));
}

Answer 1

Add code given below to your dropdown_page module, this will create a block which will be visible in blocks list. From blocks section you can assign it to any region you want.

/**
 * Implements hook_block_info().
 */
function dropdown_page_block_info() {
    $blocks = array();

    $blocks['dropdown_page_select_form'] = array(
        'info' => t('Select Layout'),
    );

    return $blocks;
}

/**
 * Implements hook_block_view().
 */
function dropdown_page_block_view($delta = '') {
    $block = array();

    switch ($delta) {
        case 'dropdown_page_select_form':
            $block['subject'] = t('Select Layout');
            $block['content'] = drupal_get_form('dropdown_page_select_form');
            break;
    }

    return $block;
}