Displaying Long Text Messages in Business Server Pages II

[Former Member]

In the first part of this log(Displaying Long Text Messages in Business Server Pages I) we examined how you obtain the long text for a T100 message from the database. In this, second part we are going to show you how to render a long text message in order that it can be displayed with a similar look and feel as the underlying application.

  Introduction  

As mentioned in the first part of this log, a long text message is delivered in SAPscript format, in this case, using the method read_log( ) from the application class cl_applog. To render and subsequently display the message with the same look and feel as the underlying application, the text formatted in SAPscript needs to be converted to HTML. You can do this easily with the function module convert_ift_to_html. This function module converts the long text message that is formatted in SAPscript to HTML, though here we are mainly interested in the message content.


Figure 1: long text message

Once we have converted the long text to HTML, the message content is extracted, the HTML tags that are not needed are deleted, and the message content is then inserted into a dynamically-generated HTMLB textview element. After the page has been rendered, its content is to be saved to the WebAS cache as a URL, which will be available for display from the browser until the cache time expires.

Implementation

It is good programming practice to separate all message handling operations from rendering and conversion operations. Therefore, our first step is to create a new class for rendering, caching, and converting the message text to HTML. The new class, CL_RENDER_PAGE, consists of nine methods, six of which are private and three of which are public.


Figure 2: class diagrams of the message classes

The main method in the class is the method cl_render_page->render( ). As explained before, it is easy to execute the whole process of converting the long text message to HTML by calling the member method to_HTMLB(). The function module CONVERT_ITF_TO_HTML is executed and returns the long text message as HTML. What we actually need is the content of the message, so we continue by deleting from the message content all the HTML tags that we do not need.

Method Render()
method render .*-----Declarations  data:         lr_grid_outer         type ref to    ifur_d2_gridlayout,         lr_system             type ref to    ifur_d2_system,         lr_renderer           type ref to    ifur_d2,         lv_content_html       type           string,         lv_htm                type           string.*----- Convert SAPscript-Text to HTML  lv_content_html = to_htmlb( is_head = is_head  it_docu_lines = it_docu_lines  ).*-----Create Layout  lr_grid_outer = create_layout( lv_content_html ).    .*-----Initialize Unified Rendering  build_path( importing er_renderer = lr_renderer er_system   = lr_system ).  clear lv_content_html.*-----Get Render  lr_renderer->render( exporting _control = lr_grid_outer changing  _html    = lv_content_html ).*-----Build Page  lv_htm = build_page(  ir_system       = lr_system                        ir_renderer     = lr_renderer                        iv_content_html = lv_content_html                        iv_titel        = iv_titel ).*------Create URL  create_url( iv_path ).*-----Cache Page  cache_page( lv_htm ).

As you can see in Figure 1, we intended to display the long text message inside a textview element and this textview inside of a tray element. If we cannot use HTMLB extension tags inside a class, we are still able to reuse part of its HTMLB rendering to get a similar look and feel as the underlying application. Therefore, the next step is to dynamically create the layout and all the elements it contains, using member method cl_render_page->create_layout(). You can dynamically create a grid layout by using the static method in factory class clur_d2_factory=>gridlayout(). However the factory class allows you to create other elements as rows, cells, textviews, and trays. Once we have the instances of the grid layout, the tray, and the textview, we continue by adding the message content to the textview and the textview to the tray context. A new layout row and a cell are then created and added to the grid layout.

Method Create_layout:
method create_layout .*-----Declarations  data:  lr_gridlayoutcell     type ref to    ifur_d2_gridlayoutcell,         lr_gridlayoutrow      type ref to    ifur_d2_gridlayoutrow,         lr_gridlayout         type ref to    ifur_d2_gridlayout,         lr_tray               type ref to    ifur_d2_tray,         lr_tabstrip           type ref to    ifur_d2_tabstrip,         lr_tabstripitem       type ref to    ifur_d2_tabstripitem,         lr_caption            type ref to    ifur_d2_caption,         lr_textview           type ref to    ifur_d2_textview.*-----Create Gridlayout  lr_grid_outer = clur_d2_factory=>gridlayout( width        = '100%'                                               height       = '100%'                                               margintop    = '0'                                               marginbottom = '0'                                               marginleft   = '0'                                               marginright  = '0' ).*-----Create Row  lr_gridlayoutrow = clur_d2_factory=>gridlayoutrow( ).*-----Add this row to layout  lr_grid_outer->rows_add( lr_gridlayoutrow ).*-----Create Cell  lr_gridlayoutcell = clur_d2_factory=>gridlayoutcell( width  = '100%'                                                       halign = ifur_d2=>cellhalign_forcedleft                                                       valign = ifur_d2=>cellvalign_top ).*-----Create Textview with the html context of the long text  lr_textview = clur_d2_factory=>textview( text   = iv_content_html                                           design = ifur_d2=>textviewdesign_standard ).*----- Embbed Content in Tray  lr_tray = clur_d2_factory=>tray( id       = 'tray01'                                   title    = 'Details'                                   design   = ifur_d2=>traydesign_plain ).*-----Add Tray to Grid  lr_tray->content = lr_textview.  lr_gridlayoutcell->content = lr_tray.  lr_gridlayoutrow->cells_add( lr_gridlayoutcell ).

Method to_HTML( 😞
*-----Declarations  data:       lt_html               type           html_t,       lv_help               type           string.*----- Convert SAPscript-Text to HTML  call function 'CONVERT_ITF_TO_HTML'    exporting      i_header    = is_head      i_title     = '----'    tables      t_itf_text  = it_docu_lines      t_html_text = lt_html.*-----Convert table to line  loop at lt_html into lv_help.    concatenate     rv_content_html     lv_help     into rv_content_html.  endloop.*-----Delete not needed HTML Tags  replace '' in rv_content_html with space. replace '' in rv_content_html with space. replace '' in rv_content_html with space. replace '' in rv_content_html with space. replace '' in rv_content_html with space. replace '' in rv_content_html with space. replace '' in rv_content_html with space. 

The next step is executed by member method cl_render_page->build_path(), which initializes some parameters and creates two main objects: system and render. These objects contain some parameters, such as minepath, stylepath, spacegifpath, and browser ID, which are needed to build the path to load javascript and mine types (see method cl_render_page->build_page() ). The object system invokes its method cl_render_page->render( ) to render the grid layout to HTML, in which the message content has been embedded.

Method build_path( 😞
*----Declarations  data:  lv_browser_id         type string,  lv_ur_jsbase          type string,  lv_basepath           type string,  lv_hostname           type string,  lv_port               type string.*-----Build tehem root path  translate iv_theme_root   to lower case.  case iv_theme_root.    when 'sap_chrome'.    lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_chrome`.    when 'sap_hcb'.       lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_hcb`.    when 'sap_highcont'.  lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_highcont`.    when 'sap_standard'.  lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_standard`.    when 'sap_tradeshow'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_tradeshow`.    when others.          lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_standard`.  endcase.* Set Browser type and version  case iv_user_agent_type.*-----I Explorer    when ihttp_user_agent_ie.      if iv_user_agent_version <= 500.*----IE5        lv_browser_id = 'ie5'.      else.*-----IE6        lv_browser_id = 'ie6'.      endif.*-----Netscape    when ihttp_user_agent_nn.      if iv_user_agent_version < 700.*------        lv_browser_id = `nn6`.      else.*------        lv_browser_id = `nn7`.      endif.*-----Default Internet Explorer 5    when others.      lv_browser_id = `ie5`.  endcase.*-----Create system intance  er_system = clur_d2_factory=>system( ).*----Build minepath, sytlepath and giftpath to load them from the browser  concatenate lv_basepath '/common/'        into er_system->mimepath.  concatenate lv_basepath '/ur/'            into er_system->stylepath.  concatenate lv_basepath '/common/1x1.gif' into er_system->spacegif.  er_renderer = clur_d2=>create( device = lv_browser_id standardevents = abap_true ).  er_renderer->set_system( er_system ).

The said method, cl_render_page->build_page(), needs some parameters as the theme_root, browser_version and agent_type are normally embedded in the HTTP request and at this point are not available in our current context. These parameters can be obtained from the objects request and runtime via the BSP application’s event_handler and the static method cl_render_page=> ser_ext_Param(), which initialize the static attributes user_agent_type, user_agent_version and theme_root of the class.

The following coding must be added to the event handler in our BSP application: Event handler OnInputProcessing:
* Application extension used to initialize the static attirbutes of the class cl_render_pagedata: lv_user_agent_type type i,      lv_user_agent_version type i,      lv_theme_root     type string.*----Get User Agent from request objectrequest->get_user_agent( importing user_agent_type    = lv_user_agent_type                                   user_agent_version = lv_user_agent_version ).*----Initialize static parameters of the class cl_render_pagecl_render_page=>set_ext_param( exporting iv_version = lv_user_agent_version                                    iv_type     = lv_user_agent_type                                    iv_theme    = runtime->application_theme ).

Once we’ve completed the content layout,method cl_render_page=>render( ) executes method renderer->render( )inininof the object render, which renders the grid layout to HTML.

Having already rendered the layout to HTML, the page can be built using method cl_render_page->build_page( ), which concatenates the page content and adds javascript, stylesheet, and HTML tags to the page. We have now seen that the HTML page containing the long text has been fully generated. However, we need to create a URL for this page. We can do this with the member method create_url(), which invokes the static interface method cl_bsp_runtime=>construct_bsp_url( ) and returns the required URL as a string. The URL consists of tree parts: host, port, application path, a guid path obtained from the method cl_applog=>create_url( ), the client number, and the end, the extension “.htm”. The client number should be added to the URL to avoid login problems in a non-default client.

URL example:
http://loco.de:50049/sap/bc/bsp/sap/test_log_handle/7dc9d39e03a71f4da0740260701b8f8c?SAP-CLIENT=400 )

Method Create_URL:
*-----Declarations  data: ls_url_param      type ihttpnvp,        lt_url_param      type tihttpnvp.*-----Add Mandant to log in in a not default mandat.  ls_url_param-name =  'SAP-CLIENT'.  ls_url_param-value = sy-mandt.  append ls_url_param to lt_url_param.*-----Create URL  cl_bsp_runtime=>if_bsp_runtime~construct_bsp_url( exporting                                                      in_application = iv_application                                                      in_page        = iv_path                                                      in_protocol    = iv_protocoll                                                      in_parameters  = lt_url_param                                                     importing                                                      out_abs_url    = iv_url ).*-----Add .htm to the URL.  concatenate  iv_url '.htm' into iv_url.
Once we have reached this point, we only need to save the rendered page to the Web As cache. First, when our generated page (long text message) is requested, the Web As sends it in response to the client. Next, an instance of the interface if_http_responce is created and the page content is added by its interface method, if_http_response->set_cdata( ). The HTTP response code is then set to 200 (OK) and the expiration time for the cache content is set by default to 180 seconds. Finally, the added content is saved as a URL in the ICM cache. As mentioned in the first part of this log series, this topic (ICM Cache) has already been covered in another web log. The content of the saved page is displayed in the ICM cache monitor. Now our message is ready to be called and displayed.


Figure 3: ICM cache monitor

Method cache_page( 😞
*-----Declarations  DATA:  li_cached_response  TYPE REF TO   if_http_response.*-----Create an intance of the cache  CREATE OBJECT li_cached_response TYPE cl_http_response EXPORTING add_c_msg = 1.*-----Set body  li_cached_response->set_cdata( iv_html ).*----- Set HTTP Status to 200  li_cached_response->set_status( code = 200 reason = 'OK' ).*-----Set cache expire  li_cached_response->server_cache_expire_rel( expires_rel = iv_expire_cache ).*-----Upload data to cache  cl_http_server=>server_cache_upload( url      = iv_url                                       response = li_cached_response ).

Closing words

The idea behind this log was more to show you how to display a long text in a separate window with same look and feel as the application. It was not intended to provide a "cut and paste" solution. The challenge here was to create a simple way of enhancing message handling to support the display of T100 message long texts. However, the implementation is rather complex. A better approach – and the next step we must undertake – will be to port this to a BSP extension.

Coding:
class-pool .*"* class pool for class CL_RENDER_PAGE*"* local type definitions*"* use this source file for any type declarations (class*"* definitions, interfaces or data types) you need for method*"* implementation or private method's signature*"* class CL_RENDER_PAGE definition*"* public declarationsclass CL_RENDER_PAGE definition  public  final  create public .*"* public components of class CL_RENDER_PAGE*"* do not include other source files here!!!public section.  class-methods SET_EXT_PARAM    importing      !IV_VERSION type I      !IV_TYPE type I      !IV_THEME type STRING .  methods GET_URL    returning      value(RV_URL) type STRING .  methods RENDER    importing      !IV_PATH type STRING      !IT_DOCU_LINES type TLINETAB      !IS_HEAD type THEAD      !IV_TITEL type STRING .*"* protected declarations*"* protected components of class CL_RENDER_PAGE*"* do not include other source files here!!!protected section.*"* private declarations*"* private components of class CL_RENDER_PAGE*"* do not include other source files here!!!private section.  types:    html_t  type standard table of htmlline .  class-data IV_THEME_ROOT type STRING .  constants IV_EXPIRE_CACHE type I value 180. "#EC NOTEXT  data IV_PROTOCOLL type STRING value 'HTTP' .  data IV_URL type STRING .  data IV_APPLICATION type STRING value 'test_log_handle' .  class-data IV_USER_AGENT_TYPE type I .  class-data IV_USER_AGENT_VERSION type I .  methods CREATE_LAYOUT    importing      !IV_CONTENT_HTML type STRING    returning      value(LR_GRID_OUTER) type ref to IFUR_D2_GRIDLAYOUT .  methods TO_HTMLB    importing      !IS_HEAD type THEAD      !IT_DOCU_LINES type TLINETAB    returning      value(RV_CONTENT_HTML) type STRING .  methods CACHE_PAGE    importing      value(IV_HTML) type STRING .  methods CREATE_URL    importing      !IV_PATH type STRING .  methods BUILD_PATH    exporting      !ER_RENDERER type ref to IFUR_D2      !ER_SYSTEM type ref to IFUR_D2_SYSTEM .  methods BUILD_PAGE    importing      !IV_CONTENT_HTML type STRING      !IR_RENDERER type ref to IFUR_D2      !IR_SYSTEM type ref to IFUR_D2_SYSTEM      !IV_TITEL type STRING    returning      value(RV_HTML) type STRING .endclass. "CL_RENDER_PAGE definition*"* macro definitions*"* use this source file for any macro definitions you need*"* in the implementation part of the class*"* local class implementation*"* local class implementation for public class*"* use this source file for the implementation part of*"* local helper classesclass CL_RENDER_PAGE implementation.*"* method's implementationsMETHOD cache_page .*---------------------------------------------------------------------** Put Page in Cache*---------------------------------------------------------------------**-----Declarations  DATA:  li_cached_response  TYPE REF TO   if_http_response.*-----Create an intance of the cache  CREATE OBJECT li_cached_response TYPE cl_http_response EXPORTING add_c_msg = 1.*-----Set body  li_cached_response->set_cdata( iv_html ).*----- Set HTTP Status to 200  li_cached_response->set_status( code = 200 reason = 'OK' ).*-----Set cache expire  li_cached_response->server_cache_expire_rel( expires_rel = iv_expire_cache ).*-----Upload data to cache  cl_http_server=>server_cache_upload( url      = iv_url                                       response = li_cached_response ).ENDMETHOD.METHOD render .*--------------------------------------------------------------------** Render messages to HTMLB*--------------------------------------------------------------------**-----Declarations  DATA:         lr_grid_outer         TYPE REF TO    ifur_d2_gridlayout,         lr_system             TYPE REF TO    ifur_d2_system,         lr_renderer           TYPE REF TO    ifur_d2,         lv_content_html       TYPE           string,         lv_htm                TYPE           string.*----- Convert SAPscript-Text to HTML  lv_content_html = to_htmlb( is_head = is_head  it_docu_lines = it_docu_lines  ).*-----Create Layout  lr_grid_outer = create_layout( lv_content_html ).    .*-----Initialize Unified Rendering  build_path( IMPORTING er_renderer = lr_renderer er_system   = lr_system ).  CLEAR lv_content_html.*-----Get Render  lr_renderer->render( EXPORTING _control = lr_grid_outer CHANGING  _html    = lv_content_html ).*-----Build Page  lv_htm = build_page(  ir_system       = lr_system                        ir_renderer     = lr_renderer                        iv_content_html = lv_content_html                        iv_titel        = iv_titel ).*------Create URL  create_url( iv_path ).*-----Cache Page  cache_page( lv_htm ).ENDMETHOD.METHOD create_url .*---------------------------------------------------------------------** Complete applications-URI                                           **---------------------------------------------------------------------**-----Declarations  DATA: ls_url_param      TYPE ihttpnvp,        lt_url_param      TYPE tihttpnvp.*-----Add Mandant for not the log in in a not default mandat.  ls_url_param-name =  'SAP-CLIENT'.  ls_url_param-value = sy-mandt.  APPEND ls_url_param TO lt_url_param.*-----Create URL  cl_bsp_runtime=>if_bsp_runtime~construct_bsp_url( EXPORTING                                                      in_application = iv_application                                                      in_page        = iv_path                                                      in_protocol    = iv_protocoll                                                      in_parameters  = lt_url_param                                                     IMPORTING                                                      out_abs_url    = iv_url ).*-----Add .htm to the URL.  CONCATENATE  iv_url '.htm' INTO iv_url.ENDMETHOD.method GET_URL .*---------------------------------------------------------------------** Get URL                                                             **---------------------------------------------------------------------* rv_url = iv_url.endmethod.METHOD build_page .*---------------------------------------------------------------------** Build HTMLB page*---------------------------------------------------------------------**-----Declarations  DATA: lv_header_html        TYPE string,        lv_body_start_html    TYPE string,        lv_body_end_html      TYPE string,        lv_ur_jsbase          TYPE string,        lv_favicon            TYPE string,        lv_build              TYPE string.*-----Build Page  CONCATENATE    lv_build `` lv_build `` lv_build `` lv_build `` lv_build `` lv_build `` INTO lv_header_html. CONCATENATE lv_build `` lv_build `

` INTO lv_body_start_html. *-----Add Tags

lv_body_end_html = ''. CONCATENATE lv_header_html lv_body_start_html iv_content_html lv_body_end_html `` INTO rv_html. ENDMETHOD. METHOD create_layout . *-------------------------------------------------------------------- * Create grid layout *-------------------------------------------------------------------- *-----Declarations DATA: lr_gridlayoutcell TYPE REF TO ifur_d2_gridlayoutcell, lr_gridlayoutrow TYPE REF TO ifur_d2_gridlayoutrow, lr_gridlayout TYPE REF TO ifur_d2_gridlayout, lr_tray TYPE REF TO ifur_d2_tray, lr_tabstrip TYPE REF TO ifur_d2_tabstrip, lr_tabstripitem TYPE REF TO ifur_d2_tabstripitem, lr_caption TYPE REF TO ifur_d2_caption, lr_textview TYPE REF TO ifur_d2_textview. *-----Create Gridlayout lr_grid_outer = clur_d2_factory=>gridlayout( width = '100%' height = '100%' margintop = '0' marginbottom = '0' marginleft = '0' marginright = '0' ). *-----Create Row lr_gridlayoutrow = clur_d2_factory=>gridlayoutrow( ). *-----Add this row to layout lr_grid_outer->rows_add( lr_gridlayoutrow ). *-----Create Cell lr_gridlayoutcell = clur_d2_factory=>gridlayoutcell( width = '100%' halign = ifur_d2=>cellhalign_forcedleft valign = ifur_d2=>cellvalign_top ). *-----Create Textview with the html context of the long text lr_textview = clur_d2_factory=>textview( text = iv_content_html design = ifur_d2=>textviewdesign_standard ). *----- Embbed Content in Tray lr_tray = clur_d2_factory=>tray( id = 'tray01' title = 'Details' design = ifur_d2=>traydesign_plain ). *-----Add Tray to Grid lr_tray->content = lr_textview. lr_gridlayoutcell->content = lr_tray. lr_gridlayoutrow->cells_add( lr_gridlayoutcell ). ENDMETHOD. "create_layout METHOD to_htmlb . *---------------------------------------------------------------------* * Render to HTMLB *---------------------------------------------------------------------* *-----Declarations DATA: lt_html TYPE html_t, lv_help TYPE string. *----- Convert SAPscript-Text to HTML CALL FUNCTION 'CONVERT_ITF_TO_HTML' EXPORTING i_header = is_head i_title = '----' TABLES t_itf_text = it_docu_lines t_html_text = lt_html. *-----Convert table to line LOOP AT lt_html INTO lv_help. CONCATENATE rv_content_html lv_help INTO rv_content_html. ENDLOOP. *-----Delete not needed HTML Tags REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. REPLACE '' IN rv_content_html WITH space. ENDMETHOD. METHOD BUILD_PATH . *---------------------------------------------------------------------* * Construct Paths *---------------------------------------------------------------------* *----Declarations DATA: lv_browser_id TYPE string, lv_ur_jsbase TYPE string, lv_basepath TYPE string VALUE '/sap/public/bc/ur/Design2002/themes/sap_tradeshow', lv_hostname TYPE string, lv_port TYPE string. *-----Build path TRANSLATE iv_theme_root TO LOWER CASE. CASE iv_theme_root. WHEN 'sap_chrome'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_chrome`. WHEN 'sap_hcb'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_hcb`. WHEN 'sap_highcont'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_highcont`. WHEN 'sap_standard'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_standard`. WHEN 'sap_tradeshow'. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_tradeshow`. WHEN OTHERS. lv_basepath = `/sap/public/bc/ur/Design2002/themes/sap_standard`. ENDCASE. CASE iv_user_agent_type. *-----I Explorer WHEN ihttp_user_agent_ie. IF iv_user_agent_version <= 500. *----IE5 lv_browser_id = 'ie5'. ELSE. *-----IE6 lv_browser_id = 'ie6'. ENDIF. *-----Netscape WHEN ihttp_user_agent_nn. IF iv_user_agent_version < 700. *------ lv_browser_id = `nn6`. ELSE. *------ lv_browser_id = `nn7`. ENDIF. *-----Default Internet Explorer 5 WHEN OTHERS. lv_browser_id = `ie5`. ENDCASE. *-----Create system intance er_system = clur_d2_factory=>system( ). *----Build minepath, sytlepath and giftpath to load them from the browser CONCATENATE lv_basepath '/common/' INTO er_system->mimepath. CONCATENATE lv_basepath '/ur/' INTO er_system->stylepath. CONCATENATE lv_basepath '/common/1x1.gif' INTO er_system->spacegif. er_renderer = clur_d2=>create( device = lv_browser_id standardevents = abap_true ). er_renderer->set_system( er_system ). ENDMETHOD. METHOD set_ext_param . *---------------------------------------------* * Set Agent type und version *---------------------------------------------* iv_user_agent_version = iv_version. iv_user_agent_type = iv_type. iv_theme_root = iv_theme. ENDMETHOD. endclass. "CL_RENDER_PAGE implementation