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phpreflectionmixins

Reflection Class and parameters in PHP


So I attempted, and possibly failed, to write a "mixin" class of sorts. It works as expected for the most part until you have multiple parameters for a class to pass in, then the world implodes. My class is as such:

class AisisCore_Loader_Mixins {

    private $_classes;

    private $_class_objects = array();

    private $_methods = array();

    public function __construct(){
        $this->init();
    }

    public function init(){}

    public function setup($class){
        if(!is_array($class)){
            throw new AisisCore_Loader_LoaderException('Object passed in must be of type $class_name=>$params.');
        }

        $this->_classes = $class;
        $this->get_class_objects();
        $this->get_methods();    
    }

    public function get_class_objects(){
        foreach($this->_classes as $class_name=>$params){
            $object = new ReflectionClass($class_name);
            $this->_class_objects[] = $object->newInstance($params);
        }
    }

    public function get_methods(){
        foreach($this->_class_objects as $class_object){
            $this->_methods = get_class_methods($class_object);
        }
    }

    public function call_function($name, $param = null){
        foreach($this->methods as $method){
            $this->isParam($method, $param);
        }
    }

    private function isParam($method, $param){
        if($param != null){
            call_user_func($method, $param);
        }else{
            call_user_func($method);
        }        
    }
}

And is extended and used in a "bridge" class as such:

class AisisCore_Template_Helpers_Loop_LoopMixins extends AisisCore_Loader_Mixins{

    private $_options;

    private $_wp_query;

    private $_post;  

    private $_components;

    public function __construct($options){
        parent::__construct();
        global $wp_post, $post;

        if(isset($options)){
          $this->_options = $options;
        }

        if(null === $wp_query){
          $this->_wp_query = $wp_query;
        }

        if(null === $post){
          $this->_post = $post;
        }

        $this->_components = new AisisCore_Template_Helpers_Loop_LoopComponents($this->_options);

        $this->setup(array(
            'AisisCore_Template_Helpers_Loop_Helpers_Loops_Single' => array($options, $this->_components),
            'AisisCore_Template_Helpers_Loop_Helpers_Loops_Query' => array($options, $this->_components),
            'AisisCore_Template_Helpers_Loop_Helpers_Loops_Page' => array($options, $this->_components),
        ));
    }

    public function init(){
        parent::init();
    }
}

Whats the issue?

Warning: Missing argument 2 for AisisCore_Template_Helpers_Loop_Helpers_Loops_Single::__construct() 
Warning: Missing argument 2 for AisisCore_Template_Helpers_Loop_Helpers_Loops_Query::__construct() 
Warning: Missing argument 2 for AisisCore_Template_Helpers_Loop_Helpers_Loops_Page::__construct() 

I thought doing something like:

array($options, $this->_components)

Takes the parameters for that class, wraps it in an array and then newInstanceArgs implodes that array putting both parameters into the class. In other words I thought i was passing two arguments??


Solution

  • The error message is telling you exactly what's going wrong:

    Warning: Missing argument 2 for BlahBlahBlah::__construct()
    

    So the issue is that all your parameters aren't being passed to the constructor when you're instantiating an object here:

    $this->_class_objects[] = $object->newInstance($params);
    

    If you consult the relevant documentation for ReflectionClass::newInstancedocs you'll see this:

    Creates a new instance of the class. The given arguments are passed to the class constructor.

    So no matter how many elements you have in the $params array you're only passing Argument 1 to the constructor with your current approach. The solution is to use ReflectionClass::newInstanceArgsdocs instead as this will expand the array of parameters and pass them as individual arguments to the constructor:

    $this->_class_objects[] = $object->newInstanceArgs($params);