Most people who start out using Zend Framework quickly come to use these two very nice features of the framework. However that may not always be the best options. The fact is that both of these approaches to executing additional actions are very hard to debug and slow (the framework has to do a full dispatch cycle for each additional action).
$this->action
The built in action view helper allows you to execute another action within your view script and echo its output directly. This is a very easy to use and powerful way to re-use actions. The action view helper is very often used in layouts to put the results of different actions into different parts of the layout.
AcitonStack
The ActionStack Front Controller plugin allows you to, in your bootstrap code, or in the action being executed, say “hey do this other action(s) also”. And so after the current request (action) has finished executing, but before the layout plugin is executed these other actions that you pushed to the stack are executed. These actions may then put their output into
different output segments on the layout – thus the ActionStack becomes a prettier and much more flexible way of putting results of different actions into different areas of your layout.
How to avoid it
The key to why you can, to a great degree, avoid using the action view helper and the ActionStack plugin in your Zend Framework application lies in the fact that you can easily access the view and the layout (thus also the individual layout output segments/areas) from your controller action function. One common use-case is where you have a layout with a menu to be included on all pages, but which is built from a database query, and a main (default) content area, plus an additional action/controller dependent content area. This is how I suggest solving this:
Query the database in your own view helper
There is nothing wrong with doing database queries in your view helpers (through a model class). It is a general misconception that view scripts and view helpers should not use the model, but there is nothing wrong with that! What they should NOT do is CHANGE the model. So: The menu, based on a database query, should be echo’ed into your layout script directly using a view helper – NOT an independent action, ie. in your layout script:
<?=$this->menu()?>
Access the view and layout directly from your controller class
It is easy in your action function to add output to a different part/output segment of the layout. Just access the layout segment directly! Thus say you use a output segment called ‘right’ in your layout, you would then put content in that way from your action function (or, if all actions should add the same content to the ‘right’ area, in your preDispatch function) directly
into the segment:
Most effective
$this->view->layout()->right = $this->view->render(’/path/to/viewscript.php’);
(running in the current view namespace)
Slightly less effective
$this->view->layout()->right = $this->view->partial(’/path/to/viewscript.php’, $data);
(running in its own view namespace)
If you absolutely MUST, you can also do the same thing with the action view helper:
$this->view->layout()->right = $this->view->action(’action’,'controller’);
(thus you can completely avoid using the ActionStack for putting action (or controller) specific contents into different parts of your layout)
You can also, like you can with ActionStack, just add, or prepend stuff to the output segment:
$this->view->layout()->right .= $this->view->render(’/path/to/viewscript.php’);
or
$this->view->layout()->right = $this->view->render(’/path/to/viewscript.php’).$this->view->layout()->right;
Final words
I hope that this post has been useful for you. Not using the action view helper and the ActionStack plugin will make your application faster and easier to debug. Most importantly though, your application will be easier to understand, because one request will always equal exactly one action!