Using Get_M method you can manage meta data of the field.
Get_I method is used to hide and unhide the field.
Get_V method is used for value help.
Get_P method is used to specify whether field is dorpdow or f4 or hyper link.
Don't know where you found Get_A method,.
Hope this helps.
GET_M is normaly used to overwrite the field label. If you do not implement this method you will get a label from the data element.
GET_A is used to switch(show/hide) a field in CRM Enhancement Package release. However, this is not relevant for customer.
GET_A is mostly used by SAP developer to switch(show/hide) a field based on which Switch active or inactive. The switch can be activated or deactivated by its Business Function.
My understanding on GET_M as you mentioned is like how we can use design layer to define the global custom Field labels.
GET_A is used to show/hide the fields based on any condition like how we will use GET_I method to Edit or Grade Out the Filed.
Please correct me If I understood wrongly.
The UI Framework has a generic M-Getter which retrives the label from DDIC. However, you can overwrite the M-Getter to return any other label. But if you define a label in Design Layer, the framework will take the label from Design Layer instead from M-Getter. And if you define a label in Configuration, the framework will take the label from the configuration instead from Design Layer.
A-Getter is meant to be used for showing or hiding field based on Switch ID. If you see the return parameter, it returns also switch ID. Using A-Getter to showing and hiding field not based on Switch ID is not recommended.
You were right. A-Getter is already exists in CRM 7.0 but it is not used. It is used for the Enhancement Package release of CRM.