如何创建带有小部件选项的自定义WordPress小部件

// Creating the widget 
class wpb_widget extends WP_Widget {
function __construct() {
parent::__construct(
// Base ID of your widget
'wpb_widget', 
// Widget name will appear in UI
__('WPBeginner Widget', 'wpb_widget_domain'), 
// Widget description
array( 'description' => __( 'Sample widget based on WPBeginner Tutorial', 'wpb_widget_domain' ), ) 
);
}
// Creating widget front-end
// This is where the action happens
public function widget( $args, $instance ) {
$title = apply_filters( 'widget_title', $instance['title'] );
// before and after widget arguments are defined by themes
echo $args['before_widget'];
if ( ! empty( $title ) )
echo $args['before_title'] . $title . $args['after_title'];
// This is where you run the code and display the output
echo __( 'Hello, World!', 'wpb_widget_domain' );
echo $args['after_widget'];
}
// Widget Backend 
public function form( $instance ) {
if ( isset( $instance[ 'title' ] ) ) {
$title = $instance[ 'title' ];
}
else {
$title = __( 'New title', 'wpb_widget_domain' );
}
// Widget admin form
?>
<p>
<label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e( 'Title:' ); ?></label> 
<input class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $title ); ?>" />
</p>
<?php 
}
// Updating widget replacing old instances with new
public function update( $new_instance, $old_instance ) {
$instance = array();
$instance['title'] = ( ! empty( $new_instance['title'] ) ) ? strip_tags( $new_instance['title'] ) : '';
return $instance;
}
} // Class wpb_widget ends here
// Register and load the widget
function wpb_load_widget() {
    register_widget( 'wpb_widget' );
}
add_action( 'widgets_init', 'wpb_load_widget' );

要有多个选项，从上面的代码更新3部分1)前端

public function widget( $args, $instance ) {
//store the options in variables
$option1 = $instance['option1'];
$option2 = $instance['option2'];
// before widget (defined by theme)
echo $args['before_widget'];
//use your options 
//(e.g. a paragraph with option1 as the text and option2 as its class for CSS)
//don't forget error/empty content handling/filters
echo "<p class='" . $option2 . "'>" . $option1 . "</p>";
// after widget (defined by theme)
echo $args['after_widget'];
}

2)后台w/Form

//
public function form( $instance ) {
    //Check if option1 exists, if its null, put "new option1" for use in the form
    if ( isset( $instance[ 'option1' ] ) ) {
        $option1 = $instance[ 'option1' ];
    }
    else {
        $option1 = __( 'new option1', 'wpb_widget_domain' );
    }
    //Repeat for option2
    if ( isset( $instance[ 'option2' ] ) ) {
        $option1 = $instance[ 'option2' ];
    }
    else {
        $option1 = __( 'new option2', 'wpb_widget_domain' );
    }
<p>
<label for="<?php echo $this->get_field_id( 'option1' ); ?>"><?php _e( 'Option1:' ); ?</label> 
<input class="widefat" id="<?php echo $this->get_field_id( 'option1' ); ?>" name="<?php echo $this->get_field_name( 'option1' ); ?>" type="text" value="<?php echo esc_attr( $option1 ); ?>" />
</p>
<p>
<label for="<?php echo $this->get_field_id( 'option2' ); ?>"><?php _e( 'Option2:' ); ?</label> 
<input class="widefat" id="<?php echo $this->get_field_id( 'option2' ); ?>" name="<?php echo $this->get_field_name( 'option2' ); ?>" type="text" value="<?php echo esc_attr( $option2 ); ?>" />
</p>

3)保存新部件设置的功能

public function update( $new_instance, $old_instance ) {
$instance = array();
$instance['option1'] = ( ! empty( $new_instance['option1'] ) ) ? strip_tags( $new_instance['option1'] ) : '';
$instance['option2'] = ( ! empty( $new_instance['option2'] ) ) ? strip_tags( $new_instance['option2'] ) : '';
return $instance;
}

从本质上讲，你只需要重复正确的事情，并确保你击中了所有3个关键领域。

这是在wordpress中创建自定义小部件的简单方法。这是纪念帖的小部件。

    <?php
    // Creating the widget 
    class commented_news_sidebar extends WP_Widget {
        function __construct() {
        parent::__construct(
        // Base ID of your widget
        'commented_news_sidebar', 
        // Widget name will appear in UI
        __('Commented News Widget', 'wpb_widget_domain'), 
        // Widget description
        array( 'description' => __( 'Your site&#8217;s Most Commented News.', 'wpb_widget_domain' ), ) 
        );
        }
        // Creating widget front-end
        // This is where the action happens
        public function widget( $args, $instance ) {
            if ( ! isset( $args['widget_id'] ) ) {
                $args['widget_id'] = $this->id;
            }
        /*$the_query = new WP_Query(array(  'orderby' => 'comment_count', 'order'=> 'DESC' ));*/
            $commentpost = new WP_Query( apply_filters( 'widget_posts_args', array(
                'cat' => $instance['showcommentedcat'],
                'orderby' => 'comment_count', 
                'posts_per_page' => 3,
                'order' => 'DESC',
    /*          'post_status' => 'publish', 
                */
            ) ) );

            if ($commentpost->have_posts()) :
            ?>
                <div class="nav-box"> <h4><?php echo $instance['title'];?></h4></h4></div><!-- nav-box -->
                <?php 
                $postthumb_id = null;
                $con = null;
                $img_url = null;
                while ( $commentpost->have_posts() ) : $commentpost->the_post();
                   ?>
                  <?php
                    $postthumb_id = get_post_thumbnail_id( get_the_ID());
                    $con = get_the_content($postthumb_id);
    /*
                    $comments_count = wp_count_comments(get_the_ID());
                    print_r($comments_count);
                    */
                    $img_url = wp_get_attachment_image_src( $postthumb_id , 'most-comment-img-size');
                  ?>
                    <div class="comm-most"><!-- comm-most -->
                    <?php $commented_cat_nm = get_cat_name($instance['showcommentedcat']);?>
                    <a href="<?php the_permalink(); ?>">
                        <img src="<?php echo $img_url[0]; ?>" alt="">
                        <span><?php echo $commented_cat_nm; ?></span>
                        <p><?php get_the_title() ? the_title() : the_ID(); ?></p>
                    </a>
                    </div><!-- comm-most -->
                <?php endwhile; ?>
                <?php
                // Reset the global $the_post as this query will have stomped on it
                wp_reset_postdata();
            endif;

        }

        // Widget Backend 
        public function form( $instance ) {
            if ( isset( $instance[ 'title' ] ) ) {
                $title = $instance[ 'title' ];
            }
            else {
                $title = __( 'New title', 'wpb_widget_domain' );
            }
            $oldcat =  $instance['showcommentedcat'];
            // Widget admin form
    ?>
          <?php
                $categories = get_categories( array(
                    'orderby' => 'name',
                ) );
            ?>
            <p>
            <label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e( 'Title:' ); ?></label> 
            <input class="widefat" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $title ); ?>" />
            <br>
            <label for="<?php echo $this->get_field_id( 'showcommentedcat' ); ?>"><?php _e( 'Category:' ); ?></label> 
            <select id="<?php echo $this->get_field_id('showcommentedcat'); ?>" name="<?php echo $this->get_field_name('showcommentedcat'); ?>" class="widefat" >
                <?php foreach ( $categories as $category ) {?>
                        <option <?php selected($instance['showcommentedcat'], esc_html( $category->name ));?> value="<?php echo $category->term_id ; ?>" <?php if($oldcat == $category->term_id){echo "selected";}?>><?php echo $category->name ; ?> </option>
                <?php } ?>
            </select>
            </p>
        <?php 
        }

        // Updating widget replacing old instances with new
        public function update( $new_instance, $old_instance ) {
            $instance = array();
            $instance['title'] = ( ! empty( $new_instance['title'] ) ) ? strip_tags( $new_instance['title'] ) : '';
            $instance['showcommentedcat'] = $new_instance['showcommentedcat'];
            return $instance;
        }
    } // Class commented_news_sidebar ends here

    // Register and load the widget
    function wpb_load_widget_commented_news() {
        register_widget( 'commented_news_sidebar' );
    }
    add_action( 'widgets_init', 'wpb_load_widget_commented_news' );