Dynamically display the title of page

<?php

 $items['tespage'] = array(
  'title callback' => 'custommodule_get_title',
  'title arguments' => array(1),
  'type' => MENU_CALLBACK,
  'page arguments' => array(5),
  'access arguments' => array('administer customworkflow'),
 );

/**
*Function to display the title dymnamically
*Parameters passed
*@param $arg
* Passing the id to get the custom name
*/
 function custommodule_get_title($arg){
  $arg = ($arg)?$arg:arg(1);
//Based on argument do the operation
  $name = custom_get_name($arg);
  return "Edit ".drupal_ucfirst($name);
 }

?>

Add a class to body tag for a particular menu

<?php
/**
* Override or insert PHPTemplate variables into the templates.
*/
//In template.php file
  function phptemplate_preprocess_page(&$vars) {
    if(arg(0) == "node" && arg(1) == 2){
      $vars['body_classes'] = $vars['body_classes']." testing";
    }
    return $vars;
  }
?>

Change or customize the system theme for a menu callback

//Put this code to the menu callback

<?php
  global $custom_theme;
  $custom_theme="acquia_marina";
?>

Example of drupal_render usage

<?php

//DRUPAL RENDER USAGE
$form['add_wf_mapping'] = array(
 '#type' => 'button',
 '#id'=>'edit-add-wf-mapping',
 '#name'=>'edit-add-wf-mapping',
 '#attributes' => array('style'=>'margin:0px'),
 '#value' => t('Map Workflow')
);
$output .=drupal_render($form['add_wf_mapping']);

echo $output;

Output  the button

?>

View unpublished content by an moderator or content editor(custom role created)

1.Create an custom module view_unpublished
2.Place this code in it

<?php

/**
* Implementation of hook_perm().
*/
function view_unpublished_perm() {
$perms = array('view all unpublished content');
foreach (node_get_types() as $type => $name) {
$perms[] = 'view unpublished ' . $type . ' content';
}
return $perms;
}

/**
* Implementation of hook_menu_alter().
*
* Modifies the path node/nid to use our access callback.
*/
function view_unpublished_menu_alter(&$items) {

$old_access_callback = $items['node/%node']['access callback'];
$items['node/%node']['access callback'] = '_view_unpublished_node_access';
$items['node/%node']['access arguments'] = array(1, $old_access_callback);
}

/**
* Returns true if the user has 'view all unpublished content' or if
* they have the permission corresponding to the node's content type.
*/
function _view_unpublished_node_access($node, $old_access_callback = "node_access") {
// Only check permissions on nodes that are unpublished.
if ($node->status == 0) {
if (user_access('view all unpublished content')) {
return TRUE;
}

if (user_access('view unpublished ' . $node->type . ' content')) {
return TRUE;
}
}
// If none of the above conditions were satisfied, then use the normal callback.
return $old_access_callback('view', $node);
}


?>

change template files based on an cck or an url

Customize templates based on CCK or URL

Drupal6
<?php
function themename_preprocess_page(&$variables) {
//Templete file for each content type
if ($variables['node']->type != "") {
$variables['template_files'][] = "page-node-" . $variables['node']->type;
}
//Seperate Templete file for the path node/3
if ((arg(0) == 'node') && is_numeric(arg(1)) && (arg(2) == NULL) && arg(1)==3) {
$variables['template_files'][] = "page-test";
}
}
?>

Drupal 7
<?php

function themeName_preprocess_page(&$vars, $hook) {
if (isset($vars['node'])) {
// If the node type is "blog_madness" the template suggestion will be "page--blog-madness.tpl.php".
$vars['theme_hook_suggestions'][] = 'page__'. $vars['node']->type;
}
}
?>