Question

我在我的项目中使用Rxjava和Retrofit2.0，它看起来像这样：

java.io.BufferedOutputStream

如果我不使用反应方式，它将是这样的：

<?php
/**
* Example Widget Class
*/
class dazzling_whats_trending extends WP_Widget {


/** constructor -- name this the same as the class above */
function dazzling_whats_trending() {
    parent::WP_Widget(false, $name = 'Dazzling Whats Trending Widget');  
}

/** @see WP_Widget::widget -- do not rename this */
function widget($args, $instance) { 
    extract( $args );
    $number    = apply_filters('number', $instance['number']);
    $offset  = $instance['offset'];
    ?>
          <div id="popular-posts" class="sidebar_content tab-pane active">


                <?php
                    $recent_posts = new WP_Query( array(
                        'showposts'           => $number,
                        'ignore_sticky_posts' => 1,
                        'post_status'         => 'publish',
                        'order'               => 'DESC',
                        'meta_key'            => 'post_views_count',
                        'orderby'             => 'meta_value_num',
                        'offset'              => $offset
                    ) );
                ?>

                <?php while($recent_posts->have_posts()): $recent_posts->the_post(); ?>
                    <li>
                        <?php the_post_thumbnail( array(336,210) ); ?>
              <h4 class="blacktext"><a href="<?php the_permalink(); ?>"><?php echo the_title(); ?></a></h4>
              <span class="orangetext">
            <?php 
              $post = get_post();
              $views = get_post_meta($post->ID, 'post_views_count', true);
              if($views > 1000){
                $views_count=$views *1/1000; 
                $views_k=round($views_count,PHP_ROUND_HALF_UP);
                echo $views_k.'K';
              }
              else {
                echo $views;
              }
            ?> VIEWS
          </span>
          <span class="graytext">| 
            <?php
              $category = get_the_category(); 
              $category_parent_id = $category[0]->category_parent;
              $category_link = get_category_link($category_parent_id);
              if ( $category_parent_id != 0 ) {
                $category_link = get_category_link($category_parent_id);
                    $category_parent = get_term( $category_parent_id, 'category' );
                    $catname = $category_parent->name;
              } else {
                $category_link = get_category_link($category_id);
                    $catname = $category[0]->name;
              }
            ?>
            <a href="<?php echo esc_url($category_link); ?>"><?php  echo $catname; ?></a>
          </span>
                    </li>
                <?php endwhile; ?>

            <?php wp_reset_postdata(); ?>

         </div> 
    <?php
}

/** @see WP_Widget::update -- do not rename this */
function update($new_instance, $old_instance) {   
$instance = $old_instance;
$instance['number'] = strip_tags($new_instance['number']);
$instance['offset'] = strip_tags($new_instance['offset']);
    return $instance;
}

/** @see WP_Widget::form -- do not rename this */
function form($instance) {  


    $number  = esc_attr($instance['number']);
    $offset  = esc_attr($instance['offset']);
    ?>
    <p>
      <label for="<?php echo $this->get_field_id('offset'); ?>"><?php _e('Offset number of posts by'); ?></label>
      <input size="3" id="<?php echo $this->get_field_id('offset'); ?>" name="<?php echo $this->get_field_name('offset'); ?>" type="text" value="<?php echo $offset; ?>" />
    </p>
    <p>
      <label for="<?php echo $this->get_field_id('number'); ?>"><?php _e('Number of posts to show:'); ?></label> 
      <input size="3" id="<?php echo $this->get_field_id('number'); ?>" name="<?php echo $this->get_field_name('number'); ?>" type="text" value="<?php echo $number; ?>" />
    </p>
    <?php 
}


} // end class example_widget
add_action('widgets_init', create_function('', 'return register_widget("dazzling_whats_trending");'));
?>

所以，我的问题是如何使用Rxjava来实现这个以及使用什么运算符？

Answer 1

使用Rx，您最终可以不再考虑“嵌套”网络请求。

如果你考虑一下，你真的不想“嵌套”网络请求，对吧？这只是代码最终看起来的样子，因为您只有AsyncTask或其他回调。

使用Rx，您最终可以编写在其结构中类似于您实际想要的代码，即链网络请求：首先做一件事，然后做另一个。

getAFromServer()
    .flatMap(new Func1<List<A>, Observable<A>>() {       
        @Override
        public Observable<A> call(List<A> list) {
            // the first flatMap is just a trick to "flatten" the Observable
            return Observable.from(list);
        }
    })
    .flatMap(new Func1<A, Observable<B>>() {
        @Override
        public Observable<A> call(A someA) {
            return getBFromServer(someA.a);
        }

    })
    .subscribe(...);

如何编写嵌套网络请求使用rxjava + retrofit2

1 个答案: