OOP: Get method from same class to another method through anonymous function - php

Question

I'm new to Object-Oriented PHP so I'm not entirely sure what my question really is, but here's the jam:
I created a WordPress plugin that adds a bunch of metaboxes on a certain custom post type created by another plugin. In my theme I need to get all the custom meta, but it's quite a lot that needs to be gotten, and usually with certain conditionals and so forth. So, I created a bunch of helper functions to simplify it. Problem is the names of all these functions are kind of a pain, so I put them inside a class in my plugin to simplify things, and my issue is that I'm having trouble combining them. Whether that's possible or not, hopefully you can help with...
So most of the helper functions (now class methods) look something like this:
public function metabox_wrapper( $code ) {
$info = get_post_meta( ID, 'blah', true);
if ( $info ) {
code( $info );
}
}
Then in my theme file I use:
global $Other_Plugins_Global // Created by the other plugin.
$class = new Class( $Other_Plugins_Global );
$class->metabox_wrapper( function( $info ) {
?>
<div>
<?php echo $info; ?>
</div>
<?php
});
The above is currently working - it displays the blah meta from the current post if the blah metadata exists. The other plugin's global variable contains the custom post type info (and therefore the meta), so I pass that through the class instance, use a method in the class to manage all the conditionals and other complicated stuff, and then use the method in the theme file, so that the conditional stuff is pre-arranged and able to be used in the same way elsewhere in the theme.
However, here's the rub: There are situations where I want something like
if (
Do this
if (
Also do this
)
)
But this (and everything like it that I've tried) does not work:
global $Other_Plugins_Global
$class = new Class( $Other_Plugins_Global );
$class->metabox_wrapper( function( $info ) {
?>
<div>
<?php echo $info; ?>
</div>
<?php
$class->other_metabox_wrapper( function( $stuff ) {
?>
<div>
<?php echo $stuff; ?>
</div>
<?php
});
});
So my question is... is there a way I can use these wrapper functions inside of each other? I've tried setting them as static and using :: in the theme, I've tried some fancy variable gymnastics that didn't work and would've been ugly af if it had, I almost raised a demon trying to call the global variable from inside the method... so at this point I'm not even sure what to Google.
Obviously for this particular example I could just use if(){}, but the conditional logic often has multiple conditions and other semi-complicated stuff, so it'd be helpful to keep that separate and able to be used in multiple places around the theme.
I will say that if this is a dumb question and you know of a completely different and more elegant way to accomplish what I'm describing, then I'm all ears.
Many thanks for the help.

Answer 1

The problem lies not in the realm of OOP, but rather in the realm of functions and function scopes. You see, when you create an anonymous function it has its own scope -- the scope of variables that are accessible. In most languages, anonymous function encloses the scope it was created in, creating a closure -- meaning it can access the copies of all variables from the parent scope. In PHP it is not the case, so in order to access $class variable from within the anonymous function you should use use: $class->metabox_wrapper(function($info) use ($class) {.
Another approach would be to bind the context to anonymous function with Closure::bind():
public function metabox_wrapper($code) {
$info = get_post_meta(ID, 'blah', true);
if ($info) {
$code = Closure::bind($code, $this);
$code($info);
}
}
Then you can use $this inside the anonymous function:
$class->metabox_wrapper(function($info) {
?>
<div>
<?php echo $info; ?>
</div>
<?php
$this->other_metabox_wrapper(function($stuff) {
?>
<div>
<?php echo $stuff; ?>
</div>
<?php
});
});
But to tell you the truth I agree with #CrisanLucian. Mixing the code with HTML in such a manner is not the best way to program.

Answer 2

First of all you have to read some Coding Standards articles
1. https://www.tutorialspoint.com/php/php_coding_standard.htm
Try to make separation between PHP code and HTML; Using Twig instead PHP make life much easy
https://aristath.github.io/blog/using-twig-in-wordpress
When you have a more help (hooks) functions better to group them into a class, or create a Helper dir structure and create a file for each scope. (e.g: Trim strings , Resize Images create different files)
After creating Helpers try to not put HTML inside; A helper suppose to return a value ( boolean ).
e.g showCampaign() => will return True;
HTML page/ TWIG page
{{ if(showCampaign()) }}
//HTML CODE IS HERE
{{ endif }}
When you have too many if/else statements is need refactor check the link above or another example: https://carlalexander.ca/mastering-php-conditionals/
happy codding!