alert_library.php

Helper.php
===
<?php 

class Helper
{
    private static $instance;
    public static $alert;

    public function __construct()
    {
        self::$alert = new Alert();
    }

    public static function init()
    {
        if (is_null(self::$instance)) {
            self::$instance = new self();
        }
        return self::$instance;
    }
}

class Alert
{
    public function __call($name, $arguments)
    {
        global $globalViewAlert;

        switch ($name) {
            case 'success': {
                return $globalViewAlert = ['level' => 'success', 'msg' => $arguments[0]];
            }
            case 'info': {
                return $globalViewAlert = ['level' => 'info', 'msg' => $arguments[0]];
            }
            case 'warning': {
                return $globalViewAlert = ['level' => 'warning', 'msg' => $arguments[0]];
            }
            case 'error': {
                return $globalViewAlert = ['level' => 'error', 'msg' => $arguments[0]];
            }
        }
    }
}

(new Helper())->init();
===


==========


alert.php
===
<?php

if (!function_exists('renderAlert')) {
    function renderAlert()
    {
        global $globalViewAlert;

        $alert = $globalViewAlert;

        if (isset($alert)) {
            if (gettype($alert['msg']) === 'array') {
                $msg = "<ul>";
                foreach ($alert['msg'] as $m) {
                    $msg .= "<li>$m</li>";
                }
                $msg .= "</ul>";
            } else {
                $msg = $alert['msg'];
            }

            switch ($alert['level']) {
                case 'success':
                    echo "<div class='alert alert-success'>{$msg}</div>";
                    break;
                case 'info':
                    echo "<div class='alert alert-info'>{$msg}</div>";
                    break;
                case 'warning':
                    echo "<div class='alert alert-warning'>{$msg}</div>";
                    break;
                case 'error':
                    echo "<div class='alert alert-danger'>{$msg}</div>";
                    break;
            }
        }
    }
}

renderAlert();
===