I'm using the MVC pattern in my application.
Now I need the view object in a model.
I don't want to add the view as a parameter for my function in the model (since I need it in other functions as well). And I don't want to keep on passing it.
Should a add the view as an attribute for the constructor of the model?
Is there another way? Shouldn't I be needing the view object in the model in the first place?
What would be the preferred way of doing it?
Example:
Controller
function someAction()
{
$somemodel->add();
}
Model
class SomeModel()
{
function add()
{
if ($view->user) {
// do stuff
$this->mail();
} else {
// do other stuff
}
}
function mail()
{
Mailer::send($view->user->email, $this->getitems(), $view->layout);
}
function getitems()
{
return Items::getitems($view->user);
}
}
If you're really doing MVC, then you won't need the view in the model, because only the controller should have access to the view.
Looking at the code you've provided, I can tell one thing: the add() method should not reference $view in any way (even for accessing its properties). Instead, the model should be provided with the $view->user value from the controller. The same goes for the mail() method.
Consider fixing those issues. Otherwise, you'll get into something worse later on.
The model should be separate from the view. So, as mkArtak said, the controller should be the only thing that communicates with the view. Which then passes only the necessary information to the model.
As for the model, it should really only deal with the information that it understands.
i.e. if you had a Car model... you don't want to build it dependent on it's factory. If you did, you would have to change your code if you wanted to build it in different factory.
The controller is where you 'bake' everything prepare for render. By bake I mean you consider any passed in $_REQUEST params, make model API calls to get the data you need, and set template variables to be rendered. Your action, at the end of this process should make a call to a template (view) you choose in order to render the 'baked' template variables.
Related
I have a problem with PHP/MVC.
This is my index controller.
<?php
class Index extends Controller {
function __construct() {
parent::__construct();
}
function index() {
$this->view->render('header');
$this->view->render('index/index');
$this->view->render('footer');
}
public function test(){
$this->model->test();
}
?>
And this, index model.
<?php
class Index_Model extends Model{
public function __construct() {
parent::__construct();
}
public function test() {
return $this->db->select('SELECT text FROM test');
}
}
}
How can I use this in "index view"?
Of course you can call controller and model methods from your views (if it wasn't possible then you'd need to put EVERYTHING in your view). The idea of MVC isn't complete separation (as some people wrongly think) but separation of the logic. This means that it is fine to pass data between the different parts of the MVC arch; the idea is that you want to try to make sure that the logic in each part is logic that is appropriate for that part.
Many people will over complicate this in search of some ideal which is just silly. I would get rid of the controller method all together and reference the model method directly in the view if all you are doing is grabbing some data to be displayed in the view. There is no reason to waste time and effort passing these results to the controller just to be passed back to the view. You will thank me for this advice once you make a truly large site and look at all of the effort you would have spent doing that (and then later maintaining all of it).
My philosophy is that a controller should be used for just that (controlling the application logic). If you want to display a sidebar with a list of the most recent post that has NOTHING to do with the controller so it shouldn't add any code to it. Save yourself some headache and call the model from the view. In the end your code is going to make more sense if you do.
In response to your question: You cannot use your controller method in the view because it doesn't return anything.
Currently I'm using a view-helper to help my debugging process. Basically I call this function and it checks if 1: I'm logged in as a developer by checking a Zend_Session_Namespace variable and 2: if the application is run in debug_mode using Zend_Registry. If both of them are true I show a number of different debug variables and any parameters I give the helper as input.
Originally this function was only intended to check that I got the right info in the objects assigned to the view, but I quickly discovered that it was useful in other places as well. At the moment the function works in controllers using $this->view, and I guess I could technically use something along new Zend_View(); or Zend_Controller_Action_HelperBroker::getStaticHelper('viewRenderer'); to get a view-object in my models, but that is just plain ugly even if it's only for debugging.
So my question is: How can I rebuild this helper into a global function (usable in models, views and Controllers) and still be able to use the Zend_Session_Namespace and Zend_Registry objects, while (as far as possible) maintaining the MVC structure.
I think if you made a static class or a singleton class, you could have all of the desired functionality without breaking your MVC structure at all.
Consider the following simple class with one static function:
<?php
class My_DebugHelper
{
public static function dump()
{
$ns = new Zend_Session_Namespace('the_namespace'); // the namespace you refer to with the developer flag
$debug_mode = Zend_Registry::get('debug_mode');
if (!isset($ns->isDeveloper) || !$ns->isDeveloper || !$debug_mode) {
return;
}
foreach(func_get_args() as $arg) {
Zend_Debug::dump($arg);
}
}
protected function __construct() {}
protected function __clone() {}
}
This code gives you:
The ability to call from anywhere in your application (model, controller, helper, view etc)
All of the protections to prevent it from being executed when called out of context
A simple base that you can expand upon
Depending on your needs, at least one thing you could do is make it static so it could store some of the information rather than access it each call, or add additional methods or specialized parameters so you could pass a Zend_View object to it if necessary and have data injected into the view.
You could call it from anywhere in your application and pass one or more values to dump:
My_DebugHelper::dump($someVar, $this->view, $model->getCustId());
I'm not sure how/what your view helper displays data currently, but hopefully that will help you merge your view helper into the generic class that you can call anywhere.
i am writing a web application and i need all the data returned/computed in all actions of one specific controller to return data to the layout (not the view).
So after each action, a controller variable needs to be passed to the layout so the layout can use it.
In detail, i want to store the calculated data in jSon in the head.
Any ideas anyone of how to do this?
I thought about a controller plugin but i have no idea of how to access the desired parameters then and i really don't want to use a singleton for all this.
Let use, this method is executed before every action
public function preDispatch() {
}
for example
public function preDispatch()
{
//calculate something
//this is an example
if($this->getRequest()->getActionName()=="admin")
{
$this->_helper->layout->setLayout('admin');
}
else
{
$this->_helper->layout->setLayout('user');
}
}
EDIT: Previous title, because no one was reading the question: "If I'm making AJAX calls in an MVC framework, is it common to have 'getter' controller methods over the model?"
It's all in the title: If I want to make an AJAX call to delete a user, that DB code clearly lives in the model $this->userModel->delete($id).
If I'm making all of the CRUD calls via AJAX, do I just have passthrough controller methods to expose those model calls to a URL?
function delete($id) {
$this->userModel->delete($id);
}
etc? This seems silly, but it also makes sense... but it also makes me feel like I'm missing something. Is this the most common pattern?
Thanks!
When it comes down to Ajax under the MVC Framework I usually tend to have each function with a specified keyword such as fetch / set.
something like this
class Users extends Controller
{
public function Fetch($id){}
public function Create(){}
public function Update($id){}
public function Remove($id){}
}
To answer your question: yes
The task of the controller is the decision maker, so that you would perform authentication checks etc within the controller for security purposes.
Think of it this way, you would not use the same controller for changing records in your administration as you would within your users front-end, but you would use the same models.
the models should be used in more places than just the front end, so you would not place a session check, input validation in the model methods as you would perform different checks depending on the location the action is taking place.
Your frontend controller would have something along the lines of:
public function Fetch($id)
{
if($this->session->get_userdata("auth_level") & USER_AUTH_LEVEL_READ)
{
//Show data
}
}
where as your administration would have:
public function Fetch($id)
{
if($this->session->get_userdata("auth_level") & IS_ADMINISTRATOR)
{
//Show data
}
}
if you place the very same check in your models then you would have generate several models that would do return the same data regardless of the location.
I have a controller which has several methods which should all share common informations. Let's say my URI format is like this:
http://server/users/id/admin/index
http://server/users/id/admin/new
http://server/users/id/admin/list
http://server/users/id/admin/delete
I need to retrieve some informations from the database for id and have them available for all methods instead of writing a line in each of them to call the model. How can I do this?
class users extends Controller {
private $mydata = array();
function users()
{
parent::Controller();
....
$this->mydata = $this->model->get_stuff($this->uri->segment(2));
}
function index()
{
$this->mydata; //hello data!
}
Here I simply hardcoded the array (which probably is a really bad idea). Nevertheless you can store the data in a codeigniter session if you need to. Codeigniter can store this data in a cookie (if it's total is less than 4kb) otherwise you can store bigger blobs of data in the database (see the docs on how to do this).
See: http://codeigniter.com/user_guide/libraries/sessions.html
Subsection: Saving Session Data to a Database
Here's some session exercise:
$this->session->set_userdata('mydata', $mydata);
....
$mydata = $this->session->userdata('mydata');
If this cannot be solved from CodeIgniters Hook mechanism, you could override the constructor method in your controller and call your own. Judging from their SVN repository you'd probably would do something like
class YourController extends Controller
{
function YourController()
{
parent::Controller();
$this->_preDispatch();
}
function _preDispatch()
{
// any code you want to run before the controller action is called
}
Might be that the call to preDispatch has to be before the call to parent. Just try it and see if it works. I didnt know they still use PHP4 syntax. Ugh :(
Based on your url structure, and the fact that codeignitor uses a MVC pattern, I'm assuming you're using mod_rewrite to format the url path into a query string for index.php. If this is the case, the value of "id" should be available at $_REQUEST['id'] at any point in the execution of the script...