我正在创建一个wordpress边栏小部件，它将显示最近的帖子。为此，我创建了一个自定义小部件(popular_posts_widget.php) 并包含在我的主题中functions.php. 我试图显示帖子标题，点击后会显示与之相关的各个帖子。但不幸的是，链接不起作用。我怎样才能解决这个问题？？

这是我的functions.php

<?php 

/****************************************************/
/* Define Constants */   
/***************************************************/

define (\'THEMEROOT\', get_stylesheet_directory_uri());
define (\'IMAGES\', THEMEROOT . \'/img\' );
define (\'FONTS\', THEMEROOT . \'/fonts\' );
define (\'JS\', THEMEROOT . \'/js\' );

/****************************************************/
/* Menus */  
/***************************************************/

function register_my_menus() {
         register_nav_menus(array(

         \'main-menu\'=> __(\'Main Menu\')
         ));
}
add_action(\'init\' , \'register_my_menus\');

if(function_exists(\'register_sidebar\')) {

    register_sidebar(
    array(
         \'name\' => __(\'Main Sidebar\'),
         \'id\' => \'main-sidebar\',
         \'description\' => __(\'The main sidebar area\'),
         \'before_widget\' => \'<div class="widget">\',
         \'after_widget\' => \'</div>\',
         \'before_title\' => \'<h2>\',
         \'after_title\' => \'</h2>\'
   ));

}

/****************************************************/
/* Add Theme Support for post thumbnail */  
/***************************************************/

if(function_exists(\'add_theme_support\')) {
   add_theme_support(\'post-formats\', array(\'link\', \'quote\', \'gallery\'));
   add_theme_support(\'post-thumbnails\', array(\'post\'));
}

/****************************************************/
/* Load Custom Widgets */  
/***************************************************/

require_once(\'functions/widget-ad-260.php\');
require_once(\'functions/popular-posts-widget.php\');
require_once(\'functions/rh_about.php\');
require_once(\'functions/rh_tags.php\');

 ?>

<?php 

/****************************************************/
/* Widget that displays a popular posts widget */  
/***************************************************/

class Popular extends WP_Widget {
    function __construct() {
        $params = array(
            \'name\' => \'Creative : Popular Posts Widget\',
            \'description\' => \'Displays recent posts of your blog\'
            );
        parent:: __construct(\'Popular\',\'\',$params);
    }

    public function form($instance) {
        //display our form in widget page
        extract($instance);
        ?>
        <p>
            <label for="<?php echo $this->get_field_id(\'title\') ?>">Title : </label>
            <input class="widefat" id="<?php echo $this->get_field_id(\'title\') ?>" name="<?php echo $this->get_field_name(\'title\') ?>" 
            value="<?php if(isset($title)) echo esc_attr($title); ?>" />
        </p>
        <?php
    }

    public function widget($args,$instance) {
        //displays our widget
        extract($args);
        extract($instance);
        echo $before_widget;
           echo $before_title .$title. $after_title;
           echo \'<div class="popular">\';
           if(have_posts()) {
            while (have_posts()) {
                the_post();
                echo "<ul>";
                echo "<li>";
                $link = the_permalink();
                echo "<a href=$link>";
                echo the_title();
                echo "</a>";
                echo "<p>";
                echo the_time(get_option(\'date_format\'));
                echo "</p>";
                echo "</li>";
                echo "</ul>";
            }
           }
           else {
            echo "<h1>No posts were found!</h1>";
           }
           echo \'</div>\';
        echo $after_widget;
    }
} 

add_action(\'widgets_init\',\'rh_register_popular\');
function rh_register_popular() {
    register_widget(\'Popular\');
}

 ?>