将变量从Controller / Action传递给Layout时，如何避免重复

Question

I am currently working on a project developed using Zend Framework, based on the structure of my web page design I have reached a point where I have to pass a small number of variables to my layout from each Controller/Action. These variables are:

<?php Zend_Layout::getMvcInstance()->assign('pageId', 'page1'); ?>
<?php Zend_Layout::getMvcInstance()->assign('headerType', '<header id="index">'); ?>

The reason for passing this information is firstly, I pass the page id as the multi column layout may change depending on the content being displayed, thus the page id within the body tag links the appropriate CSS to how the page should be displayed. Secondly I display a promotional jQuery slider only on the index page, but I need the flexibility to have it displayed on potentially multiple pages in case the wind changes and the client changes their mind.

My actual question: Is there a more appropriate method of passing this information to the Layout that I am overlooking?

I am not really questioning whether the information has to be sent, rather is there some Zend Framework feature that I have, in my haste, overlooked which would reduce the amount of repetitive redundant code which may very well be repeated in multiple Actions within the same controller?

Answer 1

You shoudn't really be passing anything from the view to the layout, for a start the view should be included IN the layout, not the other way around.

So, setting your page title should be done using similar code to what you have, but inside the controller action being called:

$this->view->headTitle()->append('Homepage');

And the other two issues - you need to rethink as I stated to begin with. Maybe you're misunderstanding the layout/view principle? If you include the different views per action, then you simply change the div id when needed, and include the header for your banner only in the index.phtml file.

Answer 2

You could turn that logic into an action helper than you can call from your controllers in a more direct way. You could also make a view helper to accomplish the same thing but view helpers usually generate data for the view rather than set properties.

// library/PageId.php
class Lib_PageId extends Zend_Controller_Action_Helper_Abstract
{
    public function direct($title, $pageId, $headerType)
    {
        $view = $this->getActionController()->view;


        $view->headTitle()->append($title);
        $view->pageId = $pageId;
        $view->headerType = $headerType;
    }
}

In your controller actions you can now do this:

$this->_helper->PageId('Homepage', 'page1', 'index');
// now pageId and headerType are available in the view and
// Homepage has been appended to the title

You will also need to register the helper path in your Bootstrap like this:

protected function _initActionHelpers()
{
    Zend_Controller_Action_HelperBroker::addPrefix('Lib');
}

Doing it like that can reduce the amount of repetitive code and remove needing to assign the values from the view. You can do it in the controller very quickly. You can also have default values in the case that the helper hasn't been called.