topic Access via 'NULL' object reference not possible. in Application Development and Automation Discussions

Access via 'NULL' object reference not possible.

Former Member — Wed, 12 Aug 2015 16:16:50 GMT

My error is this and program code is attached:

OBJECTS_OBJREF_NOTASSIGNED

CL_GUI_PDFVIEWER==============CP

BC-FES-CTL

Access via 'NULL' object reference not possible.

You attempted to use a 'NULL' object reference (points to 'nothing')

access a component (variable: " ").

An object reference must point to an object (an instance of a class)

before it can be used to access components.

Either the reference was never set or it was set to 'NULL' using the

CLEAR statement.

Program CL_GUI_PDFVIEWER==============CP

Include CL_GUI_PDFVIEWER==============CM003

Line 18

Module Tp. (METHOD)

Module name CREATE_TOOLBAR

Re: Access via 'NULL' object reference not possible.

AndyS — Thu, 13 Aug 2015 19:23:52 GMT

Hi Ricardo,

you used subclass from CL_GUI_CONTROL isn't released.

I have checked the internal coding and it seems this class is buggy.

If you run the demo report of this class you will get a dump, too.

You can you CL_GUI_HTML_VIEWER instead.

I changed your code like shown below.

That is the result.

You can find some further informations about official gui controls at

http://help.sap.com/saphelp_nwpi711/helpdata/en/d2/147a36c70d2354e10000009b38f839/content.htm?current_toc=%2Fen%2Fd8%2F147a36c70d2354e10000009b38f839%2Fplain.htm&show_children=true

Greetings

Andreas

Re: Access via 'NULL' object reference not possible.

Former Member — Fri, 14 Aug 2015 15:13:26 GMT

Thank you Andreas for your fast response. I appreciate that. Your recommendation works perfect to see my PDF outer the container when I set frame parameter to space and the in_place parameter to ' ' in the CALL Method go_html_viewer->show_url. But, if I set in_place parameter to 'X' my abap dynpro 100 doesn't show the pdf. No errors ocurrs. I'm newbie in methods and parameters and may be a problem in my dynpro design or definition or the frame setting parameter. Can you please recommend a solution. How can I set a frame parameter?

The Results screen is:

Thank you again.

Re: Access via 'NULL' object reference not possible.

AndyS — Fri, 14 Aug 2015 17:36:53 GMT

Hi Ricardo,

the parameter "in_place" indicates where the page should be displayed. Possible values:

'X': (default) Page is displayed in the SAPGUI window.
' ' : A separate browser window is opened to display the page

The other parameter "frame" is in my opinion only usefull in case of real html documents. If you have a html-frameset you can set the frame showing the content.

Here you can find more about CL_GUI_HTML_VIEWER and other CL_GUI classes.

In your usecase the default values of both parameters are good.

Wishes

Andreas

Re: Access via 'NULL' object reference not possible.

Former Member — Fri, 14 Aug 2015 19:26:14 GMT

Hi again Andreas Schaller:

I omit the frame parameter and set parameter in_place = 'X'. The problem now is that nothing happen. The container remain in a blank screen. Would you recommend a solution?

No idea of what is happening.

Re: Access via 'NULL' object reference not possible.

AndyS — Sat, 15 Aug 2015 07:32:02 GMT

Hi Ricardo,

Has your custom control drawn in screen-painter the same name as your custom-control-object in ABAP, like 'CONTROL'?

Are you able to use a simple CL_GUI_TEXTEDIT instead of CL_GUI_HTML_VIEWER, only for testing in your GUI?

Grettings

Andreas

Re: Access via 'NULL' object reference not possible.

Former Member — Mon, 24 Aug 2015 15:07:56 GMT

Than You Andreas Schaller for your support. I appreciate it. I found a solution to see the PDF: