How to alter view blocks content from controller in CakePHP 3?

问题

Inside Layouts/default.ctp you will see something like this at line 39:

        <div class="header-title">
            <span><?= $this->fetch('title') ?></span>
        </div>

fetch suggests that it is a view block. I couldn't find this view block anywhere.

Currently it just displays the capitalized plural form of controller. Meaning to say if you are at /users/add , the fetch('title'); gives you 'Users'

I want to change it. So I tried the following:

$this->set('title', 'Login');

in the /users/login controller action.

Did not work.

I also tried

$this->assign('title', 'Login');

in the /users/login controller action.

I get this error message:

Call to undefined method App\Controller\UsersController::assign()

I read the docs and from here

I get

Assigning a block’s content is often useful when you want to convert a view variable into a block. For example, you may want to use a block for the page title, and sometimes assign the title as a view variable in the controller:

Emphasis mine.

This suggests that you can use assign inside controller. I think I have proven that this is false.

Perhaps there is a typo in the documents. Please advise how I can set the title

回答1:

This is how to do it thanks to dakota of the irc channel #cakephp.

Inside UsersController.php:

$this->set('title', 'Login');

Inside src/Template/Layouts/default.ctp

above the $this->fetch('title');

write:

if (isset($title)) {
    $this->assign('title', $title); 
}

The question would be how does cakephp 3 set the default value?

Answer is found in https://github.com/cakephp/cakephp/blob/3.0/src/View/View.php#L468

Append image just in case link rot

Where you can see that it will be defaulted to the view path

回答2:

Assigning a block’s content is often useful when you want to convert a view variable into a block. For example, you may want to use a block for the page title, and sometimes assign the title as a view variable in the controller:

The above does not suggests that you should use assign in your controller (notice the bold). The above suggest that instead of using

$this->start('title');
echo $title;
$this->end()

You can use

$this->assign('title', $title);

and the $title variable should be set from your controller.

If you want to do it the proper way from your controller you have to write

$this->set('title', $title);

and from your layout/view file write

echo $title;

回答3:

Cake 3 (and 2?) give you the possibility to override the 'View' class. This is a good place to call assign().

Example:

namespace App\View;

use Cake\View\View;

class AppView extends View
{
    public function initialize()
    {
        $this->assign('the_block_name', "Hello from AppView");
    }
}

In Layout/default.ctp:

<?= $this->fetch('the_block_name') ?>

If you, as in my case, want to have a 'default' block defined, the above solution works great. You can override the default block in any view file (.ctp) like this:

$this->start('the_block_name');
    echo '<h4>Hello from current view!</h4>';
$this->end();

来源：https://stackoverflow.com/questions/26603377/how-to-alter-view-blocks-content-from-controller-in-cakephp-3

标签

cakephp

cakephp-3.0