Sertan's .dev blog

In the previous blog post we had a look at the possibilities of adding new methods and variables to existing AX7 program code using extensions. What if we need to modify, or add extra functionality to existing methods or events on existing classes, tables and forms? In that case we use AX7 events and delegates (also called ‘hooks’).

There are already plenty of events (hooks) we can subscribe in AX and extend the existing functionality without overlayering or overriding the function we need to extend. You can find those under the “Events” node of the application objects. Subscription is as easy as right clicking and selecting “Copy event handler method”, then you need to paste it into an eventhandler class and write your own logic inside:

public static class ExtensionDemoInventTableEventHandlers
{
[DataEventHandler(tableStr(InventTable), DataEventType::Deleted)]
public static void InventTable_onDeleted(Common sender, DataEventArgs e)
{
 InventTable inventTable = sender as InventTable;

//Your logic
}

}

Continue reading “AX7 Extensibility – Part 3 : Event handlers and delegates (hooks)” →

We have seen an overview of what we can do with application object extensions in the first part of this blog. Now what if we want to modify the program code or add new methods and variables to the program code of an existing object in AX7? It is possible to do it in various ways in AX7 (or D365O).

First method is of course the legacy method of creating a derived class which we want to extend, adding or overriding base methods in it and use this class in our new model instead of the base class. This solves many of the customization work we need but there might be cases this method is not desirable or we cannot modify the code of existing tables and forms like that.

Second option is to create something new called an ‘extension class’ to extend the program code of an existing object. This is simply done by creating an extension class with the template shown below using the ‘ExtensionOf’ attribute:

Continue reading “AX7 Extensibility Overview – Part 2 : Code extensions” →

In AX7 (or D365 for ..), we have two options to customize objects from an existing package, which are overlayering and extensions. On model creation, if you do not choose the package you want to modify using “Select existing package” option you create an extension model and can only change existing objects using the new AX7 extension possibilities. In this article I will mention about the basics of creating extensions (as of update 3 version), give you some tips and try to collect all together various different methods for creating extensions you can find on other resources on internet.

Extensions have several advantages over overlayering method and essential to keep your customizations ‘minimally’ affected from the system modifications done on the lower layers, like hotfixes or service packs. Using extensions instead of overlayering more than “highly recommended” by Microsoft and it seems extensibility is becoming the new modification way for the existing application elements than overlayering. It is already becoming mandatory for all ISVs and might become mandatory in the future for customer projects as well. So I recommend either not using overlayering or using it as few as possible to avoid any such workload of converting everything to extensions in the future.

Continue reading “AX7 Extensibility – Part 1 : Application object extensions” →