Show most popular posts by category - php

Question

I have a widget that shows posts with the highest number of views first. However, it actually show the posts in all categories. I would like to only show most popular posts in a particular category, how do i do that?
Here is the code:
<?php
class anthemes_hotposts extends WP_Widget {
function anthemes_hotposts() {
$widget_ops = array('description' => 'Hot Posts by Views' );
parent::WP_Widget(false, $name = 'Custom: Hot Posts by Views',$widget_ops);
}
function widget($args, $instance) {
extract( $args );
$number = $instance['number'];
$title = $instance['title'];
?>
<?php echo $before_widget; ?>
<?php if ( $title ) echo $before_title . $title . $after_title; ?>
<ul class="article_list">
<?php $inntop = new WP_Query(array('meta_key' => 'post_views_count', 'orderby' => 'meta_value_num', 'order' => 'DESC', 'posts_per_page' => $number )); ?>
<?php while ($inntop->have_posts()) : $inntop->the_post(); ?>
<li><a href="<?php the_permalink(); ?>">
<?php if ( has_post_thumbnail()) { ?>
<?php echo the_post_thumbnail('thumbnail-widget'); ?>
<?php } else { ?><img src="http://placehold.it/80x80&text=No+Image" width="80" height="80" alt="article image" /><?php } ?></a>
<div class="an-display-time"><?php echo time_ago(); ?> <?php _e('ago', 'anthemes'); ?></div><br />
<h3><?php the_title(); ?></h3>
<div class="sub-article-widget">
<div class="an-display-view"><i class="fa fa-eye"></i> <?php echo getPostViews(get_the_ID()); ?></div>
<div class="an-display-like"><?php if( function_exists('zilla_likes') ) zilla_likes(); ?></div>
<div class="an-display-comm"><i class="fa fa-comments"></i> <?php comments_popup_link('0', '1', '%'); ?></div><div class="clear"></div>
</div>
</li>
<?php endwhile; wp_reset_query(); ?>
</ul>
<?php echo $after_widget; ?>
<?php
}
function update($new_instance, $old_instance) {
$instance = $old_instance;
$instance['title'] = strip_tags($new_instance['title']);
$instance['number'] = strip_tags($new_instance['number']);
return $instance;
}
function form( $instance ) {
$instance = wp_parse_args( (array) $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 $this->get_field_name('title'); ?>" type="text" value="<?php if( isset($instance['title']) ) echo $instance['title']; ?>" />
</p>
<p>
<label for="<?php echo $this->get_field_id('number'); ?>">Number of Posts:</label>
<input class="widefat" id="<?php echo $this->get_field_id('number'); ?>" name="<?php echo $this->get_field_name('number'); ?>" type="text" value="<?php if( isset($instance['number']) ) echo $instance['number']; ?>" />
</p>
<?php } }
add_action('widgets_init', create_function('', 'return register_widget("anthemes_hotposts");')); // register widget
?>