topic Re: Changing public instance attribute in Application Development and Automation Discussions

Changing public instance attribute

Former Member — Mon, 11 Jun 2007 07:01:40 GMT

Hi all,

i'm a newbie in programming OO. So i have a little Problem with my Coding.

i have to change a value vom a structure. It an public instance attribute from the superclass. So how can i change it?

coding it like this:

go_busobj_created-ms_detail-nr = '1020'.

shows an error that go_busobj_created ist an objectreferenz and does'n own a component "ms_detail-snunr" - But in debugging i can navigate with doubleclick into ms_detail and ich can change manually thy value.

The other way i tried is using the method from a superclass that my object (go_busobj_created) inherits during runtime. But i don't know how to call it.

call METHOD CL_SUPERCLASS=>('SET_NR')
or
call METHOD ('IF_SUPERCLASS~SET_NR')

I can call static or dynamic - everytime it dumps..

Thanks for your help.

Stefan

Re: Changing public instance attribute

Peter_Inotai — Mon, 11 Jun 2007 07:06:46 GMT

Hi Stefan,

If it's an instance attribute, first you have to create an object reference to your class. Then you can modify the attribute of that instance.


data: gro_something type ref to cl_myclass.
...
create object gro_something.
...
gro_something-ms_detail-nr = '1020'.

Best regards,

Peter

Re: Changing public instance attribute

Former Member — Mon, 11 Jun 2007 07:12:07 GMT

Hi,

i defined it like this:

DATA go_busobj_created TYPE REF TO IF_BUS_OBJECT.

in this IF the Object doesn't know the methods or the attribute.

it's known only during program runtime.

the go_busobj_created is created by another method i called (create obj by template)

is it relevant?

Message was edited by:

Stefan Mett

Message was edited by:

Stefan Mett

Re: Changing public instance attribute

uwe_schieferstein — Mon, 11 Jun 2007 07:24:04 GMT

Hello Stefan

Based on my knowledge from RE-FX I assume that GO_BUSOBJ is a very generic object reference. Thus, in order to access the instance attribute MS_DETAIL you have to do a narrowing cast:

DATA:
  go_busobj       TYPE REF TO <generic class>,
  go_specific      TYPE REF TO <specific class which is a subclass of generic class>.

  go_specific ?= go_busobj.  " narrowing cast
  go_specific_created->ms_detail-nr = '1020'.

For example, the BDT function modules in RE-FX pass most (if not all) object references as TYPE REF TO cl_reca_storable. The actual object may be a contract (CL_RECN_CONTRACT), a building (CL_REBD_BUILDING) or some other RE object.

Regards

Uwe

Re: Changing public instance attribute

Former Member — Mon, 11 Jun 2007 07:37:23 GMT

Great! Thank you!

Now it works.

Have a nice day

Stefan