Error when I change the visibility of a context node

Question

Hi,
I had to change the visibility of a context node (ZActivityH) to public (it was private) in the context to access it in the method DO_HANDLE_EVENT. I used transaction BSP_WD_WORKBENCH. I verify and activate it.
As a result of changing the visibility, I have this error:
Class      CX_SY_REF_IS_INITIAL
Text:      Dereferencing of the NULL reference
Program:      ZL_CRM_IC_IRECREASON_IMPL=====CP
Include:      ZL_CRM_IC_IRECREASON_IMPL=====CM00C
Source Text Row:      8
The new source code in method DO_HANDLE_EVENT is:
DATA category TYPE STRING.
category = ztyped_context->ZActivityH->GET_CATEGORY( ATTRIBUTE_PATH = '' ).
Any idea about the problem? Can I modify the visibility of a context node?
Thank you very much for your help.
María José

Answer 1

Thanks a lot, Patrick,
My context node is null, but I don´t know why.
I have:
In Class: ZL_CRM_IC_IRECREASON_IMPL
Attribute ZTYPED_CONTEXT     type ref ZL_CRM_IC_IRECREASON_CTXT
In class: ZL_CRM_IC_IRECREASON_CTXT
Attribute ZACTIVITYH      type ref ZL_CRM_IC_IRECREASON_CN10
In class: ZL_CRM_IC_IRECREASON_CN10
Method GET_CATEGORY
In method CREATE_CONTEXT_NODES:
model = owner->create_model(
      class_name     = 'ZL_CRM_IC_IRECREASON_CN10'
      model_id       = 'ActivityH' ).                       "#EC NOTEXT
  activityh ?= model.
In view I’m filling the context node:
Regards,
María.