Custom module pages not rendering when added to admin menu

Question

I have a custom module that outputs some sql reports in a table with a csv button. These are SQL tables that are not accessible via views which is why I had to make this module.

Now when these links are accessible through the frontend (ie do not have 'admin' in the path ) the page and table's contents render just fine.

$items['custom_report/glp_report'] = array(
'title' => 'GLP Report',
'description' => 'Report for Guided Learning Pathways.',
'page callback' => 'op_reports_page',
'access callback' => 'op_reports_permission',
 //'theme callback' => 'op_theme',
'type' => MENU_NORMAL_ITEM,
);

When I switch this to an admin path only the table headers render but no content.

$items['admin/custom_report/glp_report'] = array(
'title' => 'GLP Report',
'description' => 'Report for Guided Learning Pathways.',
'page callback' => 'op_reports_page',
'access callback' => 'op_reports_permission',
 //'theme callback' => 'op_theme',
'type' => MENU_NORMAL_ITEM,
);

Theme_debug is on and I can see that on the frontend the bootstrap block.tpl serves the table correctly

<!-- BEGIN OUTPUT from 'sites/all/themes/bootstrap/templates/block/block.tpl.php' -->

however on the admin page it loads block/block.tpl

<!-- BEGIN OUTPUT from 'modules/block/block.tpl.php' -->

Hypothesis

Drupal Admin theme is different than the frontend theme. For whatever reason, this new theme uses a different template and that different template can't render my output.

Approach 1 Create custom template for the page

So I wanted to force a custom template hoping that would fix the module override:

Here is the page callback:

function op_reports_page() {
$page = drupal_render(drupal_get_form('op_reports_form', 'glp'));
$page .= op_reports_table('glp');

$page = array
(
'op_reports_page' => array
(
// Note - we will register theme_my_page in the next step
'#theme' => 'glp_reports',
'#contents' => $page,
),
);

return $page;
}

Here is the theme_hook:

function op_reports_theme()
{
  return array
  (
    'glp_reports' => array
    (
      'variables' => array('contents' => array()),
      'template' => 'op_theme', // don't add .tpl.php
    ),
  );
}

Template file:

<h2><?php print t('My Page'); ?></h2>
<div id="my_page_wrapper">
  <?php print render($contents); ?>
</div>

Outcome

While this renders for frontend, on the admin I get a blank content section.

Approach 2 force the theme through the hook_menu

Using the theme callback you can tell Drupal how the page should be rendered

Hook Menu:

  $items['admin/custom_report/glp_report'] = array(
    'title' => 'GLP Report',
    'description' => 'Report for Guided Learning Pathways.',
    'page callback' => 'op_reports_page',
    'access callback' => 'op_reports_permission',
    'theme callback' => 'op_theme', //name of bootstrap extended theme
    'type' => MENU_NORMAL_ITEM,
  );

Outcome

Blank page on admin page

Approach 3 hook_custom_theme

Hook_custom_theme should override any theme with the machine name theme

  function op_reports_custom_theme(){
    return 'op_theme';
  }

Outcome

Blank page on admin page

Ask

So while I appreciate getting stripes on my Drupal white belt, I would really just like to know the best way to make my custom module render output on an admin path.

Answer 1

Do not name your access callback op_reports_permission(). The conventional name is op_reports_access(). You accidentally implemented hook_permission(), and I bet you get some warnings when you drush cc all.

I think you have misdiagnosed the problem. If the table headers are rendering, but not the table body, then I think something is going wrong in generating the table. You have not shown us the contents of op_reports_form() nor op_reports_table(), and I suspect that is where the problem is.

I have created a test module for this issue at https://github.com/benjifisher/test-drupal-module. Note that I have tagged two releases: v1.0.0 is the minimal example, and v1.0.1 uses a custom theme function as in your first approach. Feel free to send a pull request!

Standard rules of debugging apply. Make the simplest example you can that reproduces the problem.

These are SQL tables that are not accessible via views which is why I had to make this module.

It may be easier to tell View how to handle these tables by implementing hook_views_data(). A little Google search turns up this blog post. (I cannot vouch for its accuracy, but it looks like what you need.)

Answer 2

All I can suggest is to look at page callbacks that already render on administrative pages (like the ones in core). There should be nothing special between a core or third-party module in this respect.

More thoughts:

• You should not call drupal_render() in a page callback. Return the render array and let core do the rendering
• No need for 'theme callback' in a menu definition here