Show content through POO

POO is a fairly broad concept that you can study based on this complete guide .

One of the advantages of programming classes is that they can be shared in a collaborative environment, that is, a class can involve several programmers (think of a broad program involving several programmers).

Therefore, a fundamental rule in the OOP is respect a naming convention , and respect a certain structure that each class should have.

We could also talk about encapsulation , polymorphism and other elements that would constitute the core of OOP.

A class usually represents a complete entity of our program, and should be able to handle it properly respecting the fundamentals of the OOP.

A class% co_of basic% would have the following structure:

   class Pelicula{
        private $Titulo;
        private $TituloOriginal;
        private $Anyo;
        private $Duracion;

       public function __construct($Titulo, $TituloOriginal, $Anyo, $Duracion){
            $this->Titulo = $Titulo;
            $this->TituloOriginal = $TituloOriginal;
            $this->Anyo = $Anyo;
            $this->Duracion = $Duracion;
       }

       public function getTitulo() {
          return $this->Titulo;
       }

       public function setTitulo($Titulo) {
          $this->Titulo=$Titulo;
       }       

       public function getTituloOriginal() {
          return $this->TituloOriginal;
       }       

       public function setTituloOriginalo($TituloOriginal) {
          $this->TituloOriginal=$titulo;
       }       

       public function getAnyo() {
          return $this->Anyo;
       }       

       public function setAnyo($Anyo) {
          $this->Anyo=$Anyo;
       }       

       public function getDuracion() {
          return $this->Duracion;
       }       

       public function setDuracion($Duracion) {
          $this->Duracion=$Duracion;
       }              

       public function toString() {
          return $this->Titulo. " ".$this->TituloOriginal." ".$this->Anyo." ".$this->Duracion;
       }              
   }

We see some things in this class:

To test the class above:

/*Se crea una instancia del objeto*/
$unaPelicula=new Pelicula("Indiana Jons", "IJ Título Original", 2018, "2:42");

/*Obtener el Titulo, usando el getter*/
echo $unaPelicula->getTitulo();

/*Modificar el año, mediante el setter*/
$unaPelicula->setAnyo(2014);

If toString were declared as Anyo in the class, you could do something like this:

$unaPelicula->Anyo=2017;

We would be facing a flagrant violation of Encapsulation , one of the basic principles of OOP.

I'll tell you a couple of things

1.- The idea of the OOP is modular, so it does not make much sense that you have to declare each movie within the class itself.
2. That last echo that you put there does not go, because the class is a generic structure
3.- The properties in this case do not have the reserved word var , what if they have is their access modifier as it can be   public
private
protected
4.- The methods must indicate that they are publicos , private or protegidos equally | 5.- You must not directly assign the equivalence of values and less use echo or print within the class since its purpose as I say is only to serve as a generic template; is in the instances where you can already do it since with each new object created the values that you passed in the constructor are created
6.- The constructors at least in PHP are with __construct as I show you in the example

I leave your example adapted to some of these rules for you to keep checking, greetings

<?php

    class Pelicula{
        // Defino las propiedades que tendrán los objetos
        public $Titulo;        
        public $TituloOriginal;
        public $Anio;
        public $Duracion;


        public function __construct($Titulo, $TituloOriginal, $Anio, $Duracion)
        {
            $this->Titulo = $Titulo;
            $this->TituloOriginal = $TituloOriginal;
            $this->Anio = $Anyo;
            $this->Duracion = $Duracion;

        }

        public function nuevaPelicula(){
            return  $this->Titulo.$this->TituloOriginal.$this->Anio.$this->Duracion;
        }
    }

    $obj = new Pelicula("titulo", "titulote", "2018", "123");
    echo $obj->nuevaPelicula();

//si necesitas declarar los valores de otra película, entonces creas una instancia nueva
    $obj2 = new Pelicula("titulo2", "titulito", "2017", "249");
    echo $obj2->nuevaPelicula();