单击保存时，WordPress 小部件不会更新

所以这是我第一次尝试创建一个小部件，它具有创建简单图像翻转效果的功能（如果有人想要它完成后，请给我留言）。

现在我下载了一个示例小部件并进行了一些更改，我仍然没有触及输出的 html 部分，所以忽略该位。现在我的问题是，当我单击保存时，字段中的值将恢复为默认值，并且它们没有在示例小部件上执行此操作。这是我的代码：

<?php
/**
 * Plugin Image: Rollover Widget
 * Description: A widget that creates a rollover image effect with a hyperlink.
 * Version: 0.1
 * Author: Zak Elas
 * Author URI:
 */

add_action( 'widgets_init', 'my_widget' );

function my_widget() {
    register_widget( 'MY_Widget' );
}
class MY_Widget extends WP_Widget {
    function MY_Widget() {
        $widget_ops = array( 'classname' => 'example', 'description' => __('A widget that creates a rollover image effect with a hyperlink. ', 'example') );
        $control_ops = array( 'width' => 300, 'height' => 350, 'id_base' => 'Rollover Widget' );
        $this->WP_Widget( 'example-widget', __('Example Widget', 'example'), $widget_ops, $control_ops );
    }
    function widget( $args, $instance ) {
        extract( $args );
        //Our variables from the widget settings.
        $link = apply_filters('widget_link', $instance['link'] );
        $image = $instance['image'];
        $rollover_image = $instance['rollover_image'];
        echo $before_widget;
        // Display the widget link 
        if ( $link )
            echo $before_link . $link . $after_link;
        //Display the name 
            printf( '<p>' . __('Hey their Sailor! My name is %1$s.', 'example') . '</p>', $image );

            printf( '<p>' . __('Hey their Sailor! My name is %1$s.', 'example') . '</p>', $rollover_image );

        echo $after_widget;
    }
    //Update the widget 
    function update( $new_instance, $old_instance ) {
        $instance = $old_instance;
        //Strip tags from link and name to remove HTML 
        $instance['link'] = strip_tags( $new_instance['link'] );
        $instance['image'] = strip_tags( $new_instance['image'] );
        $instance['rollover_image'] = strip_tags( $new_instance['rollover_image'] );
        return $instance;
    }

    function form( $instance ) {
        //Set up some default widget settings.
        $defaults = array( 'link' => __('Example', 'example'), 'image' => __('/images/editorial.png', 'example') , 'rollover_image' => __('/images/editorial.png', 'example') );
        $instance = wp_parse_args( (array) $instance, $defaults ); ?>

        <p>
            <label for="<?php echo $this->get_field_id( 'link' ); ?>"><?php _e('link', 'example'); ?></label>
            <input id="<?php echo $this->get_field_id( 'link' ); ?>" name="<?php echo $this->get_field_name( 'link' ); ?>" value="<?php echo $instance['link']; ?>" style="width:100%;" />
        </p>

        <p>
            <label for="<?php echo $this->get_field_id( 'image' ); ?>"><?php _e('image', 'example'); ?></label>
            <input id="<?php echo $this->get_field_id( 'image' ); ?>" name="<?php echo $this->get_field_name( 'image' ); ?>" value="<?php echo $instance['image']; ?>" style="width:100%;" />
        </p>
        <p>
            <label for="<?php echo $this->get_field_id( 'rollover_image' ); ?>"><?php _e('rollover_image:', 'example'); ?></label>
            <input id="<?php echo $this->get_field_id( 'rollover_image' ); ?>" name="<?php echo $this->get_field_name( 'image' ); ?>" value="<?php echo $instance['rollover_image']; ?>" style="width:100%;" />
        </p>

    <?php
    }
}
?>

这是示例小部件代码

<?php
/**
 * Plugin Name: A simple Widget
 * Description: A widget that displays authors name.
 * Version: 0.1
 * Author: Bilal Shaheen
 * Author URI: http://gearaffiti.com/about
 */

add_action( 'widgets_init', 'my_widget' );

function my_widget() {
    register_widget( 'MY_Widget' );
}
class MY_Widget extends WP_Widget {
    function MY_Widget() {
        $widget_ops = array( 'classname' => 'example', 'description' => __('A widget that displays the authors name ', 'example') );
        $control_ops = array( 'width' => 300, 'height' => 350, 'id_base' => 'example-widget' );
        $this->WP_Widget( 'example-widget', __('Example Widget', 'example'), $widget_ops, $control_ops );
    }
    function widget( $args, $instance ) {
        extract( $args );
        //Our variables from the widget settings.
        $title = apply_filters('widget_title', $instance['title'] );
        $name = $instance['name'];
        $show_info = isset( $instance['show_info'] ) ? $instance['show_info'] : false;
        echo $before_widget;
        // Display the widget title 
        if ( $title )
            echo $before_title . $title . $after_title;
        //Display the name 
        if ( $name )
            printf( '<p>' . __('Hey their Sailor! My name is %1$s.', 'example') . '</p>', $name );

        if ( $show_info )
            printf( $name );

        echo $after_widget;
    }
    //Update the widget 
    function update( $new_instance, $old_instance ) {
        $instance = $old_instance;
        //Strip tags from title and name to remove HTML 
        $instance['title'] = strip_tags( $new_instance['title'] );
        $instance['name'] = strip_tags( $new_instance['name'] );
        $instance['show_info'] = $new_instance['show_info'];
        return $instance;
    }

    function form( $instance ) {
        //Set up some default widget settings.
        $defaults = array( 'title' => __('Example', 'example'), 'name' => __('Bilal Shaheen', 'example'), 'show_info' => true );
        $instance = wp_parse_args( (array) $instance, $defaults ); ?>
        //Widget Title: Text Input.
        <p>
            <label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e('Title:', 'example'); ?></label>
            <input id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" value="<?php echo $instance['title']; ?>" style="width:100%;" />
        </p>
        //Text Input.
        <p>
            <label for="<?php echo $this->get_field_id( 'name' ); ?>"><?php _e('Your Name:', 'example'); ?></label>
            <input id="<?php echo $this->get_field_id( 'name' ); ?>" name="<?php echo $this->get_field_name( 'name' ); ?>" value="<?php echo $instance['name']; ?>" style="width:100%;" />
        </p>

        //Checkbox.
        <p>
            <input class="checkbox" type="checkbox" <?php checked( $instance['show_info'], true ); ?> id="<?php echo $this->get_field_id( 'show_info' ); ?>" name="<?php echo $this->get_field_name( 'show_info' ); ?>" /> 
            <label for="<?php echo $this->get_field_id( 'show_info' ); ?>"><?php _e('Display info publicly?', 'example'); ?></label>
        </p>
    <?php
    }
}
?>