I have a Wordpress site with some Custom Post Types.
I need to add a new criteria for filtering the "Activities" post type. This criteria is a calendar control, so after clicking the control, the user can select a date, and after that, click "Filter", and search posts with this additional date criteria.
Attached you'll find what I'm looking for.
The date criteria selected, must search trough the posts, and compare with a post_meta which contains a specific date for the post.