work fine in default opencart checkout example..
- $this->model_setting_event->addEvent('custom_name', 'catalog/view/theme/default/template/checkout/payment_method/after', 'event_function');
- $this->model_setting_event->addEvent('custom_name', 'catalog/controller/checkout/payment_method/save/after', 'event_function');
- $this->model_setting_event->addEvent('custom_name', 'catalog/model/checkout/order/addOrder/before', 'event_function');
how can i make it work with journal3 one checkout page?
opencart 3.0.2.0

There are 2 approaches, you can choose either one to implement based on which approach is more applicable to your situation:
1. Replace the view file before rendering the output
Create an event script:
catalog/controller/event/my_event.phpCreate your own checkout page view:
catalog/view/theme/journal3/template/journal3/checkout/my_checkout_page.twigResult:
2. Modify the html through the output
Create an event script:
catalog/controller/event/my_event.phpResult: