I followed what James was saying and used the $_GET method. Here’s how I made it work, hopefully it will help someone:
(I’m assuming you know how to create WordPress page templates, and know how to create ACF submit forms)
1. Add a button on your single.php that sends the post id with $_GET to a page that we will create next:
global $post;
$postID = $post->ID; ?>
<a href="./page-with-form/?post=<?php echo $postID; ?>">Edit Post Button</a>
2. Create a page template with the ACF form in it. This page from the ACF documentation has an example on how to edit a specific post with a form. You’ll just have to set the post id dynamically in this case. This is what my form looks like:
<?php acf_form(array(
'post_id' => $post_id, //Variable that you'll get from the URL
'post_title' => true,
'post_content' => true,
'fields' => array('_thumbnail_id', 'ask_for_donations'), //The name of the custom fields I want to show on the form
'submit_value' => 'Update Content',
'return' => '%post_url%' //Returns to the original post
)); ?>
3. To read the post id that has been passed on the URL (will look like: ?post=number) add the following line on the page template somewhere before the form starts:
$post_id = $_GET["post"];
