i suck at programming i suck at programming - 3 months ago 10
PHP Question

Access a member function of an object that is a member variable of a parent class

I'm trying to access a function of an object from a child class, where the object is a protected variable of the parent.

I'm not entirely sure the best way to go about this... any help or pointers would be appreciated.

Below is how I have it setup now, but it's not working. It gives the following error:


Catchable fatal error: Argument 1 passed to App\Parent::__construct()
must be an instance of App\Object, none given, called in
Controller.php on line 25 and defined in Parent.php on line 12


So as I understand the error, I need to somehow pass an instance of the Parent class into the Child class. But this seems like an anti-pattern because it's extending the Parent class. I must be missing something basic.

Parent.php

class Parent
{
protected $object;

public function __construct(Object $object) // line 12
{
$this->object = $object;
}

}


Child.php

class Child extends Parent
{
public function doStuff()
{
return parent::$object->objectFunction());
}

}


Controller.php

...

namespaces etc

...

public function control()
{
$parent = new Parent(new Object($variable));

$child = new Child(); // line 25
$child->doStuff();
}

Answer

Dont instantiate a seperate parent class, it will be instantiated as part of instantiating the child class.

Also pass the object to the child instantiation and create a __construct() method and pass the parameter on to it.

class Child extends Parent
{
    public __construct($var)
    {
        parent::__construct($var);
    }

    public function doStuff()
    {
        return parent::$object->objectFunction());
    }

}

Controller.php

public function control()
{
    //$parent = new Parent(new Object($variable));

    $child = new Child(new Object($variable)); // line 25
    $child->doStuff();
}
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