Problems passing instantiated object by function parameter with php

Question

I have a file php that instance a class, however I am not able to pass this instantiated object as parameter to another class.

Example:

$usuario = new Usuario();
$email = new Email();
$email->send($usuario);

In class Email I can’t use the class getters and setters user.

class Email {
    function send($usuario) {
        mail($usuario->getId());
    }
}

Answer 1

in the email class in your send method before the parameter specifies the obj q will pass type

public function send(Usuario $usuario){
// seu codigo
}

I hope that’s what you’re looking for

Answer 2

The problem you’re having is Dependency injection .

The dependency of one class occurs when "injected", passes one class to be worked within the other.

This means that in order to have an injection of dependency, the instantiation of an object must not take place within the class, but outside it and then injected.

One of the ways to accomplish this is by injecting the external class through the construction method.

Let’s take a look at the example:

<?php

class Email  
{
    public function send()
    {
        // TODO
    }
}

class Usuario  
{
    protected $email;

    //Injeção de dependência através do método construtor
    public function __construct(Email $email)
    {
        $this->email = $email;
    }

    public function porEmail()
    {
        $this->email->send();
    }
}

__Construct() is how to declare a constructor method in PHP, different from languages like Java where the same class name is used, for example: public Usuario().

Note that now when calling the method $command->porEmail() we’re actually triggering the method send() class $email , for example, we can do so:

$email = new email();

$anunciar = new Usuario($email);
$anunciar->porEmail();

Note that the class Usuario receives by addiction injection $email. This whole process that we’ve done means dependency injection. You see how simple it is?