Thanks Arjun for your quick reply.
I have gone through both the links but none worked for me. I have tried the below classes but none worked me.
1. cl_bsp_wd_appl_model=>get_appl_model
2. CL_CRM_UI_EXT_NAV_SERVICE=>GET_EXT_NAV_DESCRIPTOR - Returned blank.
Below return the URL for start page. However I would need to URL of the current page. Incase if I am in sales order screen I would need the sales order page URL.
cl_bsp_wd_appl_model=>get_appl_model(
EXPORTING
iv_bsp_appl = 'CRM_UI_START '
iv_model_type = 'CL_BSP_WD_APPL_MODEL_RTTI'
RECEIVING
rv_model = lv_appl_model
EXCEPTIONS
OTHERS = 1 ).
IF sy-subrc <> 0.
MESSAGE ID sy-msgid TYPE 'E' NUMBER sy-msgno
WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
EXIT.
ENDIF.
rv_url = lv_appl_model->get_start_url( ).