Access via 'NULL' object reference not possible

[Former Member]

Hi,

I have created a simple web dynpro program which add and remove records,

I am also planning on using FPM_OIF_COMPONENT to configure my program, however I wanted to test my code (Actions & methods) by creating a web dynpro application and this is the error I'm getting every time I am trying to login. it didn't work even with a blank view embedded to my window.

you help is highly appreciated.

Thanks

sap/bc/webdynpro/sap/ztest was not called due to an error.

Note

The following error text was processed in the system LR1 : Access via 'NULL' object reference not possible.

The error occurred on the application server and in the work process 0 .

The termination type was: RABAX_STATE

The ABAP call stack was:

Method: PREPARE_NAVIGATION of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: MODIFY_VIEW_ASSEMBLY of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: IF_WDR_VIEW_DELEGATE~WD_INVOKE_EVENT_HANDLER of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: INVOKE_EVENTHANDLER of program CL_WDR_DELEGATING_VIEW========CP

Method: FIRE_EVENT of program CL_WDR_COMPONENT==============CP

Method: IFWDR_INTERNAL_API~RAISE_EVENT of program SAPLWDR_RG_PROXY_FACTORY

Method: IF_COMPONENTCONTROLLER~FIRE_PREPARE_NAVIGATION_EVT of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: WDDOBEFORENAVIGATION of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: IF_WDR_COMPONENT_DELEGATE~WD_DO_BEFORE_NAVIGATION of program /1BCWDY/W626HUHUS4NGX9SADQSK==CP

Method: DO_BEFORE_NAVIGATION of program CL_WDR_DELEGATING_COMPONENT===CP

[Former Member · Accepted solution]

Hi,

Step1: Analyse the code in st22.

Step2: Delete get lead selection and all declared attributes from your code. Just read the node.

Step3: change the cordinality to 0..1 (if there is no records exists, empty screen will show instead of dump)

I hope it solves your problem.

Best Regards

Ravi

[Former Member]

thanks Ravi Golla, i had a similar error with another action, I changed the cordinality to 0-1

and so far its working fine.

[Former Member]

Thanks Prashant, that was really helpful

what i did though is that I generated the popup box through the wizard code and it worked just fine.

[uday_gubbala2]

Hi Abdul,

Try going to ST22 and check from where exactly this error is being triggered. It would help you pinpoint the problematic source more quickly. Check the "What Happened" & "Error Analysis" & "How to correct the error" sections.

Regards,

Uday

[Former Member]

Appears to be NULL pointer exception.

This types of error occur in situations like

DATA:

node_utility TYPE REF TO if_wd_context_node,

elem_utility TYPE REF TO if_wd_context_element,

stru_utility TYPE if_v_podetails=>element_utility .

• navigate from <CONTEXT> to <UTILITY> via lead selection

node_utility = wd_context->get_child_node( name = if_v_podetails=>wdctx_utility ).

• get element via lead selection

elem_utility = node_utility->get_element( ).

elem_utility end up being NULL

-below statement will give the kind of error----

• get all declared attributes

elem_utility->get_static_attributes(

IMPORTING

static_attributes = stru_utility ).

so thoroughly check this. Also check if CARDINALITY of the NODE is set 1...N .

Greetings

Prashant