Passing a Variable to a Function Hooked to Genesis Entry Content

Question

I'm working with a custom page template in Genesis and need to remove the post content and replace it when a certain condition is set. That part is working fine, but I also need to display information from a variable in the new content.

It seems simple, but something isn't working, and I think it's that I don't understand how to pass a variable into a function correctly. I'm assuming that a variable assigned outside of a function will be available in the function. Here's my template:

//* Template Name: Notification Template

$notice ="ALERT!"; //This will be set dynamically from code above, but I'll keep it simple for now. 

if($notice){

        //echo $notice ; // If I echo here, it displays at the top of the page.

        remove_action( 'genesis_entry_content', 'genesis_do_post_content' );

        add_action ( 'genesis_entry_content', 'do_custom_content', 5 );

        function do_custom_content(){                           

            echo $notice; // This is not displaying anything!
            echo 'Test Output'; //This text does display

        }
    }

When I echo the $notice in the do_custom_content() function, nothing is happening. So, it is probably that I don't understand how the php is working, since $notice is not passing through into the do_custom_content() function.

Answer 1

If you are going to be setting the notice dynamically, what I would do is just pull in the notice in the callback function. But if you can't do that for whatever reason, you can do a little wizardry like so:

if( $notice ) {

    remove_action( 'genesis_entry_content', 'genesis_do_post_content' );

    add_action ( 'genesis_entry_content', function() use ($notice) {
        echo $notice;
    }, 5 );

}

This takes advantage of the php use keyword available to anonymous functions.