基于WP Plugin Boilerplate的插件返回错误“警告:call_user_func_array()期望参数 - Plugin based on WP Plugin Boilerplate returning error "Warning: call_user_func_array() expects parameter 1 to be a valid callback"

Plugin based on WP Plugin Boilerplate returning error "Warning: call_user_func_array() expects parameter 1 to be a valid callback"

我正在构建一个基于Wordpress plugin Boilerplate(面向对象编程)的Wordpress插件，当调用在我的自定义管理仪表板菜单中显示我的插件管理页面的函数时，我面临着一个困难。

在我的类中，我调用我的自定义菜单方法，当菜单显示得很好时，它就工作了。

private function define_admin_hooks() {
    $plugin_admin = new myPlugin_Admin( $this->get_plugin_name(), $this->get_version() );
    $this->loader->add_action( 'admin_enqueue_scripts', $plugin_admin, 'enqueue_styles' );
    $this->loader->add_action( 'admin_enqueue_scripts', $plugin_admin, 'enqueue_scripts' );
    // Load CPTs
    $this->loader->add_action( 'admin_init', $plugin_admin, 'create_cpt_person' );
    $this->loader->add_action( 'admin_menu', $plugin_admin, 'setup_admin_menus' );
    $this->loader->add_action( 'parent_file', $plugin_admin, 'set_current_menu' );
}

然后执行我的setup_admin_menus方法。

public static function setup_admin_menus() {
    $page_title = 'myPlugin';
    $menu_title = 'myPlugin';
    $capability = 'manage_options';
    $menu_slug  = 'myplugin_admin';
    $function   = 'display_admin_page'; // This is what triggers the showing of my admin page once I click on the parent menu (as if you were clicking on "Pages" in your admin dashboard)
    $icon_url   = 'dashicons-admin-page';
    $position   = 3;
    add_menu_page(
        $page_title,
        $menu_title,
        $capability,
        $menu_slug,
        $function,
        $icon_url,
        $position
        );
    $submenu_pages = array(
        // Post Type :: Person
        array(
            'parent_slug'   => 'myplugin_admin',
            'page_title'    => 'People',
            'menu_title'    => 'People',
            'capability'    => 'read',
            'menu_slug'     => 'edit.php?post_type=person',
            'function'      => null
            )
        );
    // Add each submenu item to custom admin menu.
    foreach($submenu_pages as $submenu){
        add_submenu_page(
            $submenu['parent_slug'],
            $submenu['page_title'],
            $submenu['menu_title'],
            $submenu['capability'],
            $submenu['menu_slug'],
            $submenu['function']
            );
    }
}

这个函数叫做

public static function display_admin_page() {
    echo '<div class="wrap">';
    echo '<h2>Welcome To WordPets</h2>';
    echo '<p>This is the custom admin page created from the custom admin menu.</p>';

    echo '</div><!-- end .wrap -->';
    echo '<div class="clear"></div>';
}

但是每当我去我的插件的管理页面，我得到警告:call_user_func_array()期望参数1是一个有效的回调，函数'display_admin_page'没有找到或无效的函数名在/Users/Lazhar/dev/wp-includes/plugin.php上496，它不显示任何东西，但错误信息。

任何帮助都将非常感激:)

尝试将您的display_admin_page()方法放在类之外

function display_admin_page() {
    echo '<div class="wrap">';
    echo '<h2>Welcome To WordPets</h2>';
    echo '<p>This is the custom admin page created from the custom admin menu.</p>';

    echo '</div><!-- end .wrap -->';
    echo '<div class="clear"></div>';
}

另一种方法(而不是将function放在类之外)是通过将类方法作为数组传递:

    $page_title = 'myPlugin';
    $menu_title = 'myPlugin';
    $capability = 'manage_options';
    $menu_slug  = 'myplugin_admin';
    $function   = array($this, 'display_admin_page');  //This will properly get the class method function name

这是引用函数(类方法)的正确方式。