Working with GeneratePress Hooks

warning

Hook callbacks run on every request that reaches the hook. Keep callbacks small and safe, and always escape dynamic output.

Working with GeneratePress Hooks Explained

Hook concept	What it means	Example
Action	Runs code at a point in execution	add_action( 'generate_before_header', ... )
Filter	Modifies a value and returns it	add_filter( 'generate_sidebar_layout', ... )
Priority	Controls ordering	add_action( ..., 5 ) vs 10
Remove callback	Disable default behavior	remove_action( 'hook', 'callback', 10 )

Why It Matters

• Hooks are the update-safe customization path for GeneratePress.
• Hooks reduce template overrides (and therefore upgrade debt).
• You can debug hooks with grep and with small, labeled outputs.

How It Works

GeneratePress defines hook points with do_action() and apply_filters(). Default theme behavior is attached via add_action() and add_filter(). Your child theme registers additional callbacks.

flowchart LR
  HOOK[do_action / apply_filters] --> DEF[Default callbacks]
  HOOK --> CHILD[Child callbacks]
  CHILD --> OUT[Output change]

Practical Walkthrough

Step 1: Discover Hook Points (Theme Side)

discover-hook-points.sh

cd /var/www/html/wp-content/themes/generatepress
grep -R "do_action( 'generate_" -n inc templates | head -n 80

Step 2: Discover Default Callbacks

discover-default-callbacks.sh

cd /var/www/html/wp-content/themes/generatepress
grep -R "add_action( 'generate_" -n inc | head -n 80

Step 3: Add a Child Theme Hook (Safe Test)

wp-content/themes/generatepress-child/inc/hooks.php

<?php

add_action( 'generate_before_header', function() {
    echo '<div class="gp-hook-test">Hook test: before header</div>';
} );

Step 4: Use a Filter for Layout Decisions

wp-content/themes/generatepress-child/inc/filters.php

<?php

add_filter( 'generate_sidebar_layout', function( $layout ) {
    if ( is_page( 'landing' ) ) {
        return 'no-sidebar';
    }

    return $layout;
} );

Practical Examples

Example 1: Use Priorities to Control Ordering

wp-content/themes/generatepress-child/inc/hooks.php

<?php

add_action( 'generate_before_header', function() {
    echo '<div class="notice notice--early">Priority 5</div>';
}, 5 );

add_action( 'generate_before_header', function() {
    echo '<div class="notice notice--default">Priority 10</div>';
}, 10 );

Example 2: Remove a Default Callback (Pattern)

Workflow:

1. Find add_action() in the parent theme (hook + callback + priority).
2. Remove it in the child theme with the same values.

wp-content/themes/generatepress-child/functions.php

<?php

add_action( 'after_setup_theme', function() {
    // Pattern only: replace with real hook/callback/priority from grep.
    // remove_action( 'generate_footer', 'generate_some_callback', 10 );
} );

Example 3: Build a Hook Map for a Region

map-header-hooks.sh

cd /var/www/html/wp-content/themes/generatepress
grep -R "do_action( 'generate_" -n inc/structure/header.php | head -n 120

Best Practices

Practice	Why
Escape output	Prevent XSS
Keep callbacks small	Easier rollback
Prefer filters for decisions	Deterministic behavior
Use actions for markup	Clear output boundaries
Document hook name + scope	Avoid mystery behavior

Troubleshooting

Symptom	Cause	Fix
Hook output not visible	Wrong hook or rule	Confirm hook exists with grep and test logged-out
Duplicate output	Registered twice	Search child theme for duplicate add_action
White screen	PHP syntax error	Check /usr/local/lsws/logs/error.log
Layout differs on some pages	Conditional mismatch	Verify is_page() slug/ID and rule scope

Hands-On

1. Discover 5 hook points in inc/structure/header.php.
2. Attach a banner to one header hook.
3. Move the banner to a different hook and document the placement difference.
4. Remove the banner and confirm rollback.

Quick Reference

hooks-cheatsheet.sh

cd /var/www/html/wp-content/themes/generatepress
grep -R "do_action( 'generate_" -n inc templates | head

What's Next

• Next: Using Elements with Child Themes
• Related: Hook Elements