Booker25 allows you to define an interface which you can use to add your own custom logic whenever the Reservation Template being edited changes. You can use this to update dependent fields or display validation errors, for example.
To add your own logic on Template editing:
- Create a global class that implements the Callable interface (see https://developer.salesforce.com/docs/atlas.en-us.apexcode.meta/apexcode/apex_interface_System_Callable.htm)
- Create a Custom Setting (of type B25 System Setting) with name 'Template On Change Class' and as value the name of the class you created in step 1.
The created class is then expected to handle two different actions: getChangeHandlerInfo and onChange.
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