Insight about nesting of blocks
In this page, we are going to expose a little variation of the previous example. We now consider the need of showing a set of custom values that must be assigned to each user we previously have shown.
Now supposing the need of adding a new column to the previous table containing distinct roles for each user. So we need to rearrange the template templates\nested_blocks.htpl.tpl in the following way:
<!DOCTYPE html>
<html>
<head>
<title>Users list</title>
</head>
<body>
<h1>Users list</h1>
<h3>{CurrentAction}</h3>
<table border="1">
<thead>
<tr>
<th>User</th>
<th>Email</th>
<th>Actions</th>
<th>Roles</th>
<tr>
</thead>
<tbody>
<!-- BEGIN Users -->
<tr>
<td>{UserName}</td>
<td>{UserEmail}</td>
<td>
<ul>
<!-- BEGIN UserActions -->
<li><a href="{GLOBAL:SITEURL}/nested_blocks/do_action/{ActionName}/{UserEmail}">{ActionCaption}</a> </li>
<!-- END UserActions -->
</ul>
</td>
<td>
<ul>
<!-- BEGIN {UserEmail}Roles -->
<li>{UserRoleName}</li>
<!-- END {UserEmail}Roles -->
</ul>
</td>
</tr>
<!-- END Users -->
</tbody>
</table>
</body>
</html>In the table header, we simply added a new column containing the caption Role. In the body, we also added a new column but containing a new block. We assigned the name {UserEmail}Roles to this block with the purpose of dynamically generate many distinct block name, in the format 'UserEmailRoles', for how many users will be shown in the table.
You can better understand this result by running http://localhost/nested_blocks. You will obtain:
Now, if you will give a look inside the source code below, regarding the HTML that was dynamically generated, you will find these blocks named [email protected], [email protected], and [email protected]:
<!DOCTYPE html>
<html>
<head>
<title>Users list</title>
</head>
<body>
<h1>Users list</h1>
<h3>Please, perform an action on user</h3>
<table border="1">
<thead>
<tr>
<th>User</th>
<th>Email</th>
<th>Actions</th>
<th>Roles</th>
<tr>
</thead>
<tbody>
<!-- BEGIN Users -->
<tr>
<td>Mark</td>
<td>[email protected]</td>
<td>
<ul>
<!-- BEGIN UserActions -->
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/email/[email protected]">Send email</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/edit/[email protected]">Edit information</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/erase/[email protected]">Delete user</a> </li>
<!-- END UserActions -->
</ul>
</td>
<td>
<ul>
<!-- BEGIN [email protected] -->
<li>{UserRoleName}</li>
<!-- END [email protected] -->
</ul>
</td>
</tr>
<tr>
<td>Elen</td>
<td>[email protected]</td>
<td>
<ul>
<!-- BEGIN UserActions -->
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/email/[email protected]">Send email</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/edit/[email protected]">Edit information</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/erase/[email protected]">Delete user</a> </li>
<!-- END UserActions -->
</ul>
</td>
<td>
<ul>
<!-- BEGIN [email protected] -->
<li>{UserRoleName}</li>
<!-- END [email protected] -->
</ul>
</td>
</tr>
<tr>
<td>John</td>
<td>[email protected]</td>
<td>
<ul>
<!-- BEGIN UserActions -->
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/email/[email protected]">Send email</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/edit/[email protected]">Edit information</a> </li>
<li><a href="https://server.local/mvccourse/nested_blocks/do_action/erase/[email protected]">Delete user</a> </li>
<!-- END UserActions -->
</ul>
</td>
<td>
<ul>
<!-- BEGIN [email protected] -->
<li>{UserRoleName}</li>
<!-- END [email protected] -->
</ul>
</td>
</tr>
<!-- END Users -->
</tbody>
</table>
</body>
</html>Now, by having distinct blocks regarding each user's roles, for dynamically assigning him the corresponding set of values, we need to rearrange the views\NetsedBlocks by adding the method setUsersRoles($usersRoles). See the code below and also pay attention to its comments:
<?php
namespace views;
use framework\View;
class NestedBlocks extends View
{
/**
* @override framework\View __construct()
*/
public function __construct($tplName = null)
{
if (empty($tplName)) {
$tplName = "/nested_blocks";
}
parent::__construct($tplName);
}
/**
* Shows the given $user in the block Users
* of tempalates\nested_blocks.html.tpl
*
* @param array $users Array of users in the format:
* array( array('Username'=>'','UserEmail'=>'') )
*/
public function setUsersBlock($users)
{
$this->openBlock("Users");
foreach ($users as $user) {
$this->setVar("UserName", $user["UserName"]);
$this->setVar("UserEmail", $user["UserEmail"]);
$this->parseCurrentBlock();
}
$this->setBlock();
}
/**
* Shows the given $actions in the block UserActions
* of tempalates\nested_blocks.html.tpl
*
* @param array $actions Array of actions in the format:
* array( array('ActionName'=>'','ActionCaption'=>'') )
*/
public function setUserActionsBlock($actions)
{
$this->openBlock("UserActions");
foreach ($actions as $action) {
$this->setVar("ActionName", $action["ActionName"]);
$this->setVar("ActionCaption", $action["ActionCaption"]);
$this->parseCurrentBlock();
}
$this->setBlock();
}
/**
* Shows the given $usersRoles in the block {UserEmail}Roles
* of tempalates\nested_blocks.html.tpl
*
* @param array $usersRoles Array of users roles in the format:
* array ( array("UserEmail"=>'',"UserRoles"=> array(r1,r2...,rn)))
*/
public function setUsersRoles($usersRoles)
{
foreach ($usersRoles as $userRoles ) {
$email = $userRoles["UserEmail"];
$roles = $userRoles["UserRoles"];
$this->openBlock("$email"."Roles");
foreach ($roles as $roleName) {
$this->setVar("UserRoleName", $roleName);
$this->parseCurrentBlock();
}
$this->setBlock();
}
}
}Finally we udate the controllers\NestedBlocks for providing users' roles data and for handling the View
<?php
namespace controllers;
use framework\Controller;
use views\NestedBlocks as NestedBlockView;
class NestedBlocks extends Controller
{
/**
* @override framework\Controller __construct()
*/
public function __construct()
{
$this->view = new NestedBlockView();
parent::__construct($this->view);
$actions = $this->getUserActions();
$this->view->setUserActionsBlock($actions);
$users = $this->getUsersData();
$this->view->setUsersBlock($users);
$usersRoles = $this->getUsersRoles();
$this->view->setUsersRoles($usersRoles);
}
/**
* Set the default behaviour when no actions is performed
*/
protected function autorun($parameters = null)
{
$this->view->setVar("CurrentAction","Please, perform an action on user");
}
/**
* Provides users data.
*
* @return array Array of users in the
* format array( array('Username'=>'','UserEmai'=>'') )
*/
private function getUsersData()
{
$users = array(
array('UserName' => 'Mark', 'UserEmail' => '[email protected]'),
array('UserName' => 'Elen', 'UserEmail' => '[email protected]'),
array('UserName' => 'John', 'UserEmail' => '[email protected]')
);
return $users;
}
/**
* Provides users actions.
*
* @return array Array of actions in the format:
* array( array('ActionName'=>'','ActionCaption'=>'') )
*/
private function getUserActions()
{
$userActions = array(
array("ActionName" => "email" ,"ActionCaption" => "Send email"),
array("ActionName" => "edit" ,"ActionCaption" => "Edit information"),
array("ActionName" => "erase","ActionCaption" => "Delete user")
);
return $userActions;
}
/**
* Provides users roles.
*
* @return array Array of users roles in the format:
* array ( array("UserEmail"=>'',"UserRoles"=>array(r1,r2...,rn)))
*/
private function getUsersRoles()
{
$usersRoles = array(
array( "UserEmail" => "[email protected]",
"UserRoles" => array("admin","webmaster","moderator")
),
array( "UserEmail" => "[email protected]",
"UserRoles" => array("editor","webmaster","user")
),
array( "UserEmail" => "[email protected]",
"UserRoles" => array("user","editor")
)
);
return $usersRoles;
}
/**
* Performs the given action on a given user.
*
* @param string $actionName The action to performs
* @param string $userEmail The user email on which to perform the action
*/
public function doAction($actionName,$userEmail)
{
$currentAction = "Current action: $actionName on user $userEmail";
$this->view->setVar("CurrentAction",$currentAction);
$this->render();
}
}Now by running http://localhost/nested_blocks you will see the following result:
Keep in mind that when you nesting of blocks you have to manage the correct sequence on how to produce the repetitions of the data in order to obtain the desired output. In this example, in fact, when coding the controller __construct, we first generated the data relating to the actions common to each user. Then we produced the list of users, also producing distinct blocks for each user's specific roles. Finally, we have enhanced the roles for each distinct block in the format UserEmailRole. If you try to change this sequence, the result could not be correct.
In this page, we discussed another dynamic behavior you can obtain when using the nesting of blocks. Although we used the nesting of blocks, or even blocks in general, to produce simple HTML list, you must take in consideration that you can apply them on different GUI components like, for example, options' list, radio buttons, check boxes, divs and so on.
In the next page, we starting to introduce another important entity of MVC design pattern: the Model