Ok so I have some gaps in my understanding of PHP OOP, classes and functions specifically, this whole constructor class deal. I use both Zend and CI but right now Im trying to figure this out in CI as it is less complicated.

So all Im trying to do is understand how to call a function from a view page in code igniter. I understand that might go against MVC but Im working with an api and search results not from my database, so basically, I want to define a function in my class that I am able to call in one of my view pages.. and I keep getting "Fatal error: Call to undefined function functionname" error no matter what I try.

I thought I just had to declare

public function testing() {
    echo "testing testing 123;
}

but calling that from the view I get that error. Then I read something about having to go parent::Controller();

in the index of the class where the testing function also resides? But that didnt work either. Anyways, ya, can someone explain what I need to do in order to call the "testing()" function on one of my view pages? and clarification on the constructor class and what exactly parent::Controller() even does, would be much appreciated as well.