the_post_thumbnail with lazyload JQ plugin

Question

I need to modify the_post_thumbnail function to run "Lazyload" on it, i think there is two solutions :

1- modify the args to be something like this

the_post_thumbnail('product', array('data-original'=>$src, 'src'=>'grey.gif'));

(((NOT WORKING!)))

2- get only the image url from the function ... i've tried alot of snippets and nothing worked for me , like this one !

$thumbnail_src = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), "size" );

any ideas??

thanks

Answer 1

If you want to apply lazyload to each attachment image, you can just add your hoot to wp_get_attachment_image_attributes filter:

add_filter( 'wp_get_attachment_image_attributes', 'wpse8170_add_lazyload_to_attachment_image', 10, 2 );
function wpse8170_add_lazyload_to_attachment_image( $attr, $attachment ) {
    $attr['data-original'] = $attr['src'];
    $attr['src'] = 'grey.gif';
    return $attr;
}

Or if you can use second approach:

$thumbnail_src = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), "size" );
// add more attributes if you need
printf( '<img src="grey.gif" data-original="%s"/>', esc_url( $thumbnail_src[0] ) ); 

Answer 2

If you dont want to use a hook, in the loop you can do like this:

$loop = new WP_Query( array( 'posts_per_page' => -1 ) );
while ( $loop->have_posts() ) : $loop->the_post(); 

    global $post;
    if ( $image_id = get_post_thumbnail_id( $post->ID ) ){

        if ($src = wp_get_attachment_image_src( $image_id, 'full' )){

                $item.= '<img class="lazy" data-original="' . $src[0] . '"/>';
        }

    }

endwhile; wp_reset_query();

Answer 3

Add to your template's functions.php:

function lazyload_image( $html ) {
    $html = str_replace( 'src=', 'data-src=', $html );
    return $html;
}

...

add_filter( 'post_thumbnail_html', 'lazyload_image');

Personally i'm using my own lazyload plugin, unveil.