Confused with PHP model controller view style - php

Question

Am getting my hands wet with this whole MVC thing and am really lost. I have a mysql table tblowner (ownerid,ownername).
Now what I want is to view the detail and edit it.
created the MVC directories and began with index.php
index.php?view=owner&action=view
require('controllers/controller.php');
$controller=new controller();
controllers/controller.php
class controller {
function controller(){
//Check action and view.
$view="home";
$allowedViews=array("home","owner");
if(isset($_GET['view'])){
$view=strtolower($_GET['view']);
if (!in_array($_GET['view'],$allowedViews)){
$view="home";
}
}
//requested action?
$action="view";
if(isset($_GET['action'])){
$action=strtolower($action);
}
//require model based on view now.
$controllerClass=$view.'controller';
require('controllers/'.$controllerClass.".php");
$controller=new $controllerClass($action);
}
}
models/ownermodel.php
class ownermodel
{
//contains two methods: edit and view related. Thats all.
//**********************************************************************
function ownermodeledit()
{
//edits owner data. It is always update since program cames prefilled with data.
if (isset($_POST['btnedit']))
{
//save changes.
}
else
{//show form now.
$this->showEditForm();
}
}
//**********************************************************************
function showEditForm($msg = '')
{
if ($msg)
{
echo '<p class="error">' . $msg . '</p>';
}
$ownerInfo = $this->ownermodelview();
if (is_array($ownerInfo))
{
?>
<form action="index.php?action=edit&view=owner" method="POST" id="frmeditowner" name="frmeditowner">
Name: <input type="text" id="oname" name="oname" value="<?php echo $ownerInfo['ownername']; ?>"/>
<?php
}//if(is_array($ownerInfo)) {
else
{
echo '<p class="error">There was an error retrieving owner information</p>';
}
}
//**********************************************************************
function ownermodelview()
{
//views model. return an array here
$mydb = new dbACW();
$params = array();
$return = "";
$result = $mydb->runSelectQuery("SELECT * FROM tbllicencee LIMIT 1", $params);
if (is_array($result) && count($result) > 0)
{
$return = array();
foreach ($result as $info)
{
$return['ownerid'] = $info['id'];
$return['ownername'] = $info['ownername'];
}
}
return $return;
}
}
That calls e.g. ownercontroller.php providing the necessary action (i.e. edit). And the model is where am lost at.
For viewing owner info, a method in the model would return an array containing information and a method in the viewer would display that array in anyway.
But for actions such as edit, what's the role of the view at all? Where would the form to edit the info be made?
And the view...currently it is inform of OOP (with class stuff). But if view is supposed to make the job of a web author easier to play around design? If it has a bunch of PHP code inside it, what differentiates it from a model?
Sorry for the long post...

Answer 1

In MVC structure, there is three main terms - Model, View & Controller, which sometimes confuses people.
In Model, we basically defines the classes with for the db interactions. Say, if I am trying to create a school management system, then I would be creating a class student_model, in which I defines the functions that will write to db or read from db, etc. Like, readStudentDetails(), insertNewStudent(), etc.
In View, we just display the contents to the user. So, basically we don't do much tasks in here rather than just echoing the outputs in HTML. For example, we have a View named home.php. And it will contain just the html and some echoing of data. That's all. No major processing or calculations and other stuff is done in Views. It's just for outputting the data to the user only.
Controller is basically an intermediary between Model and View. So, it's in Controller class that accepts HTTP requests, calls the model classes to do db interaction and access the views to display the outputs, etc.
If you are looking for a simple existing framework to learn this, try CodeIgniter: https://ellislab.com/codeigniter/user-guide/overview/mvc.html
It's pretty easy to follow the documentation and it's simple to use too. But there are other frameworks, like Zend Frameworks, etc. But for beginners, in my opinion, CodeIgniter is the best!
Hope this helps.