Php Wordpress-添加菜单页面，[$this，'；函数'；]不是有效的类名或对象

我想理解为什么我不能在它自己的类中使用[$this，'function']

这项工作：

init.php

if ( is_admin() )
{
    require ( dirname ( __FILE__ ) . '/inc/admin/Admin.php' );
    add_action('admin_menu', ['Mango\Admin', 'adminMenu'] );
}

/inc/admin/admin.php-版本1（工作）

---

回答可能有点晚，但它可能也会帮助其他人

如果函数是插件中某个类的成员，则应该是
引用为数组（$this'function_name'）


感谢您有远见地发布了一个老问题的正确答案。你的答案已经6年多了，它仍然帮助了我！
<?php namespace Mango;

class Admin
{
    public function adminMenu()
    {
    //this is the main item for the menu
    add_menu_page(
        'Mango Settings', //page title
        'Mango Settings', //menu title
        'manage_options', //capabilities
        'mango-settings', //menu slug
        [ 'Mango\Admin', 'settingsPage' ] // LOOK HERE *******
    );
    }

    public function settingsPage()
    {
        echo 'This is a test';
    }
}

<?php namespace Mango;

class Admin
{
    public function adminMenu()
    {
    //this is the main item for the menu
    add_menu_page(
        'Mango Settings', //page title
        'Mango Settings', //menu title
        'manage_options', //capabilities
        'mango-settings', //menu slug
        [ $this, 'settingsPage' ] // LOOK HERE *******
    );
    }

    public function settingsPage()
    {
        echo 'This is a test';
    }
}

class Admin
{
    public function adminMenu()
    {
    //this is the main item for the menu
     add_menu_page(
        'Mango Settings', //page title
        'Mango Settings', //menu title
        'manage_options', //capabilities
        'mango-settings', //menu slug
        array( $this, 'settingsPage' ) // LOOK HERE *******
    );
    }

    public function settingsPage()
    {
        echo 'This is a test';
    }
}