Passing arguments in PHP Class via Singleton instance - php

Question

I am new to OOP so please bear with me.
I have defined a singleton trait to store instances of all classes and it all works fine when I call the classes with className::get_instance(). However, I can't figure how to pass arguments to a class's constuctor function with Singleton?
This is my Singleton trait:
trait Singleton{
final public static function get_instance() {
static $instance = [];
$called_class = get_called_class();
if( !isset( $instance[ $called_class ] ) ) {
$instance[$called_class] = new $called_class();
}
return $instance[ $called_class ];
} }
And this is my New_Post class
class New_Post{
use Singleton;
protected function __construct( $first_name, $last_name, $email, $phone, $date ){
$this->first_name = $first_name;
$this->last_name = $last_name;
$this->email = $email;
$this->phone = $phone;
$this->date = $date;
}
}
Now I want to call this class from a different file so normally I use:
New_Post::get_instance();
But as you can see in the New_Post constructor function, I need to pass $arg1 and $arg2 to its instance. How to go about passing them. Thanks.

Answer 1

Change get_instance() to take arguments and pass them along when calling $called_class().
<?php
trait Singleton{
final public static function get_instance(...$args) {
static $instance = [];
$called_class = get_called_class();
if( !isset( $instance[ $called_class ] ) ) {
$instance[$called_class] = new $called_class(...$args);
}
return $instance[ $called_class ];
}
}
class New_Post{
use Singleton;
protected function __construct( $first_name, $last_name, $email, $phone, $date ){
$this->first_name = $first_name;
$this->last_name = $last_name;
$this->email = $email;
$this->phone = $phone;
$this->date = $date;
}
}
$post = New_Post::get_instance("First", "Last", "email", "123-456-7890", "today");
var_dump($post);
DEMO