OOPS in ABAP

former_member1284402 · ‎01-18-2008

HI GURU'S ,

i m new for OOPS in ABAP. can anybody tell me from OOPS how many topics are used in ABAP? if possible then plz. send me step by step procedure for creating each .

my e-mail : saurabh.nitin@gmail.com

regards saurabh .

Former Member · ‎01-18-2008

Check these links.

/thread/415717 [original link is broken]

/thread/481861 [original link is broken]

Check this for 7 steps to create OOPS ALV

https://www.sdn.sap.com/irj/sdn/wiki?path=/display/abap/7%2bsteps%2bto%2bcreate%2boops%2balv

Regards,

Maha

Former Member · ‎01-18-2008

Hi, this may help you.

OOPs ABAP uses Classes and Interfaces which uses Methods and events.

If you have Java skills it is advantage for you.

There are Local classes as well as Global Classes.

Local classes we can work in SE38 straight away.

But mostly it is better to use the Global classes.

Global Classes or Interfaces are to be created in SE24.

SAP already given some predefined classes and Interfaces.

This OOPS concepts very useful for writing BADI's also.

So first create a class in SE 24.

Define attributes, Methods for that class.

Define parameters for that Method.

You can define event handlers also to handle the messages.

After creation in each method write the code.

Methods are similar to ABAP PERFORM -FORM statements.

After the creation of CLass and methods come to SE38 and create the program.

In the program create a object type ref to that class and with the help of that Object call the methods of that Class and display the data.

Example:

REPORT sapmz_hf_alv_grid .

Type pool for icons - used in the toolbar

TYPE-POOLS: icon.

TABLES: zsflight.

To allow the declaration of o_event_receiver before the
lcl_event_receiver class is defined, decale it as deferred in the
start of the program

CLASS lcl_event_receiver DEFINITION DEFERRED.

*----

G L O B A L I N T E R N A L T A B L E S

*----

*DATA: gi_sflight TYPE STANDARD TABLE OF sflight.

To include a traffic light and/or color a line the structure of the
table must include fields for the traffic light and/or the color

TYPES: BEGIN OF st_sflight.

INCLUDE STRUCTURE zsflight.

Field for traffic light

TYPES: traffic_light TYPE c.

Field for line color

types: line_color(4) type c.

TYPES: END OF st_sflight.

TYPES: tt_sflight TYPE STANDARD TABLE OF st_sflight.

DATA: gi_sflight TYPE tt_sflight.

*----

G L O B A L D A T A

*----

DATA: ok_code LIKE sy-ucomm,

Work area for internal table

g_wa_sflight TYPE st_sflight,

ALV control: Layout structure

gs_layout TYPE lvc_s_layo.

Declare reference variables to the ALV grid and the container

DATA:

go_grid TYPE REF TO cl_gui_alv_grid,

go_custom_container TYPE REF TO cl_gui_custom_container,

o_event_receiver TYPE REF TO lcl_event_receiver.

DATA:

Work area for screen 200

g_screen200 LIKE zsflight.

Data for storing information about selected rows in the grid

DATA:

Internal table

gi_index_rows TYPE lvc_t_row,

Information about 1 row

g_selected_row LIKE lvc_s_row.

*----

C L A S S E S

*----

CLASS lcl_event_receiver DEFINITION.

PUBLIC SECTION.

METHODS:

handle_toolbar FOR EVENT toolbar OF cl_gui_alv_grid

IMPORTING

e_object e_interactive,

handle_user_command FOR EVENT user_command OF cl_gui_alv_grid

IMPORTING e_ucomm.

ENDCLASS.

----

CLASS lcl_event_receiver IMPLEMENTATION

----

CLASS lcl_event_receiver IMPLEMENTATION.

METHOD handle_toolbar.

Event handler method for event toolbar.

CONSTANTS:

Constants for button type

c_button_normal TYPE i VALUE 0,

c_menu_and_default_button TYPE i VALUE 1,

c_menu TYPE i VALUE 2,

c_separator TYPE i VALUE 3,

c_radio_button TYPE i VALUE 4,

c_checkbox TYPE i VALUE 5,

c_menu_entry TYPE i VALUE 6.

DATA:

ls_toolbar TYPE stb_button.

Append seperator to the normal toolbar

CLEAR ls_toolbar.

MOVE c_separator TO ls_toolbar-butn_type..

APPEND ls_toolbar TO e_object->mt_toolbar.

Append a new button that to the toolbar. Use E_OBJECT of
event toolbar. E_OBJECT is of type CL_ALV_EVENT_TOOLBAR_SET.
This class has one attribute MT_TOOLBAR which is of table type
TTB_BUTTON. The structure is STB_BUTTON

CLEAR ls_toolbar.

MOVE 'CHANGE' TO ls_toolbar-function.

MOVE icon_change TO ls_toolbar-icon.

MOVE 'Change flight' TO ls_toolbar-quickinfo.

MOVE 'Change' TO ls_toolbar-text.

MOVE ' ' TO ls_toolbar-disabled.

APPEND ls_toolbar TO e_object->mt_toolbar.

ENDMETHOD.

METHOD handle_user_command.

Handle own functions defined in the toolbar

CASE e_ucomm.

WHEN 'CHANGE'.

PERFORM change_flight.

LEAVE TO SCREEN 0.

ENDCASE.

ENDMETHOD.

ENDCLASS.

*----

S T A R T - O F - S E L E C T I O N.

*----

START-OF-SELECTION.

SET SCREEN '100'.

&----

*& Module USER_COMMAND_0100 INPUT

&----

MODULE user_command_0100 INPUT.

CASE ok_code.

WHEN 'EXIT'.

LEAVE TO SCREEN 0.

ENDCASE.

ENDMODULE. " USER_COMMAND_0100 INPUT

&----

*& Module STATUS_0100 OUTPUT

&----

MODULE status_0100 OUTPUT.

DATA:

For parameter IS_VARIANT that is sued to set up options for storing
the grid layout as a variant in method set_table_for_first_display

l_layout TYPE disvariant,

Utillity field

l_lines TYPE i.

After returning from screen 200 the line that was selected before
going to screen 200, should be selected again. The table gi_index_rows
was the output table from the GET_SELECTED_ROWS method in form
CHANGE_FLIGHT

DESCRIBE TABLE gi_index_rows LINES l_lines.

IF l_lines > 0.

CALL METHOD go_grid->set_selected_rows

EXPORTING

it_index_rows = gi_index_rows.

CALL METHOD cl_gui_cfw=>flush.

REFRESH gi_index_rows.

ENDIF.

Read data and create objects

IF go_custom_container IS INITIAL.

Read data from datbase table

PERFORM get_data.

Create objects for container and ALV grid

CREATE OBJECT go_custom_container

EXPORTING container_name = 'ALV_CONTAINER'.

CREATE OBJECT go_grid

EXPORTING

i_parent = go_custom_container.

Create object for event_receiver class
and set handlers

CREATE OBJECT o_event_receiver.

SET HANDLER o_event_receiver->handle_user_command FOR go_grid.

SET HANDLER o_event_receiver->handle_toolbar FOR go_grid.

Layout (Variant) for ALV grid

l_layout-report = sy-repid. "Layout fo report

*----

Setup the grid layout using a variable of structure lvc_s_layo

*----

Set grid title

gs_layout-grid_title = 'Flights'.

Selection mode - Single row without buttons
(This is the default mode

gs_layout-sel_mode = 'B'.

Name of the exception field (Traffic light field) and the color
field + set the exception and color field of the table

gs_layout-excp_fname = 'TRAFFIC_LIGHT'.

gs_layout-info_fname = 'LINE_COLOR'.

LOOP AT gi_sflight INTO g_wa_sflight.

IF g_wa_sflight-paymentsum < 100000.

Value of traffic light field

g_wa_sflight-traffic_light = '1'.

Value of color field:
C = Color, 6=Color 1=Intesified on, 0: Inverse display off

g_wa_sflight-line_color = 'C610'.

ELSEIF g_wa_sflight-paymentsum => 100000 AND

g_wa_sflight-paymentsum < 1000000.

g_wa_sflight-traffic_light = '2'.

ELSE.

g_wa_sflight-traffic_light = '3'.

ENDIF.

MODIFY gi_sflight FROM g_wa_sflight.

ENDLOOP.

Grid setup for first display

CALL METHOD go_grid->set_table_for_first_display

EXPORTING i_structure_name = 'SFLIGHT'

is_variant = l_layout

i_save = 'A'

is_layout = gs_layout

CHANGING it_outtab = gi_sflight.

*-- End of grid setup -

Raise event toolbar to show the modified toolbar

CALL METHOD go_grid->set_toolbar_interactive.

Set focus to the grid. This is not necessary in this
example as there is only one control on the screen

CALL METHOD cl_gui_control=>set_focus EXPORTING control = go_grid.

ENDIF.

ENDMODULE. " STATUS_0100 OUTPUT

&----

*& Module USER_COMMAND_0200 INPUT

&----

MODULE user_command_0200 INPUT.

CASE ok_code.

WHEN 'EXIT200'.

LEAVE TO SCREEN 100.

WHEN'SAVE'.

PERFORM save_changes.

ENDCASE.

ENDMODULE. " USER_COMMAND_0200 INPUT

&----

*& Form get_data

&----

FORM get_data.

Read data from table SFLIGHT

SELECT *

FROM zsflight

INTO TABLE gi_sflight.

ENDFORM. " load_data_into_grid

&----

*& Form change_flight

&----

Reads the contents of the selected row in the grid, ans transfers
the data to screen 200, where it can be changed and saved.

----

FORM change_flight.

DATA:l_lines TYPE i.

REFRESH gi_index_rows.

CLEAR g_selected_row.

Read index of selected rows

CALL METHOD go_grid->get_selected_rows

IMPORTING

et_index_rows = gi_index_rows.

Check if any row are selected at all. If not
table gi_index_rows will be empty

DESCRIBE TABLE gi_index_rows LINES l_lines.

IF l_lines = 0.

CALL FUNCTION 'POPUP_TO_DISPLAY_TEXT'

EXPORTING

textline1 = 'You must choose a line'.

EXIT.

ENDIF.

Read indexes of selected rows. In this example only one
row can be selected as we are using gs_layout-sel_mode = 'B',
so it is only ncessary to read the first entry in
table gi_index_rows

LOOP AT gi_index_rows INTO g_selected_row.

IF sy-tabix = 1.

READ TABLE gi_sflight INDEX g_selected_row-index INTO g_wa_sflight.

ENDIF.

ENDLOOP.

Transfer data from the selected row to screenm 200 and show
screen 200

CLEAR g_screen200.

MOVE-CORRESPONDING g_wa_sflight TO g_screen200.

LEAVE TO SCREEN '200'.

ENDFORM. " change_flight

&----

*& Form save_changes

&----

Changes made in screen 200 are written to the datbase table
zsflight, and to the grid table gi_sflight, and the grid is
updated with method refresh_table_display to display the changes

----

FORM save_changes.

DATA: l_traffic_light TYPE c.

Update traffic light field
Update database table

MODIFY zsflight FROM g_screen200.

Update grid table , traffic light field and color field.
Note that it is necessary to use structure g_wa_sflight
for the update, as the screen structure does not have a
traffic light field

MOVE-CORRESPONDING g_screen200 TO g_wa_sflight.

IF g_wa_sflight-paymentsum < 100000.

g_wa_sflight-traffic_light = '1'.

C = Color, 6=Color 1=Intesified on, 0: Inverse display off

g_wa_sflight-line_color = 'C610'.

ELSEIF g_wa_sflight-paymentsum => 100000 AND

g_wa_sflight-paymentsum < 1000000.

g_wa_sflight-traffic_light = '2'.

clear g_wa_sflight-line_color.

ELSE.

g_wa_sflight-traffic_light = '3'.

clear g_wa_sflight-line_color.

ENDIF.

MODIFY gi_sflight INDEX g_selected_row-index FROM g_wa_sflight.

Refresh grid

CALL METHOD go_grid->refresh_table_display.

CALL METHOD cl_gui_cfw=>flush.

LEAVE TO SCREEN '100'.

ENDFORM. " save_changes

chk this blog

/people/vijaybabu.dudla/blog/2006/07/21/topofpage-in-alv-using-clguialvgrid

Reward if Helpful.

Regards Madhu.

Former Member · ‎01-18-2008

Hi,

The Object-Oriented Language Extension

ABAP Objects support object-oriented programming. The ABAP Objects is a complete set of object-oriented statements, which has been introduced into the ABAP language. This object-oriented extension of ABAP builds on the existing language and is fully compatible with it.

The Object Orientation (OO), also known as the object-oriented paradigm, is a programming model that unites data and functions in objects. You can not only use ABAP Objects in existing programs, but also work with and use a conventional ABAP in new ABAP Objects programs. The rest of the ABAP language is primarily intended for structured programming, where data is stored in a structured form in database tables and function-oriented programs access and work with it.

Moreover, we should know that the object-oriented enhancement of ABAP is based on the models of Java and C++. It is compatible with external object interfaces such as DCOM and CORBA. The implementation of object-oriented elements in the kernel of the ABAP language has considerably increased response times when you work with ABAP Objects. Some other objects, such as SAP Business Objects and GUI objects, which are already object-oriented by themselves, are also benefiting from being incorporated into ABAP Objects.

About Classes

The classes are templates for objects. An abstract description of an object is the class. You could say it is a set of instructions for building an object. The attributes of objects are defined by the components of the class, which describe the state and behavior of objects.

Local and Global Classes

In ABAP Objects, classes can be declared either globally or locally. You define global classes and interfaces in the Class Builder (Transaction SE24.} in the ABAP Workbench. In the R/3 Repository, they are stored centrally in class pools in the class library. In an R/3 System, all of the ABAP programs can access the global classes. The local classes are defined within an ABAP program. Local classes and interfaces can only be used in the program in which they are defined. When you use a class in an ABAP program, the system first searches for a local class with the specified name. If it does not find one, then it looks for a global class. Apart from the visibility question, there is no difference between using a global class and using a local class.

However, there is a significant difference in the way that local and global classes are designed. If you are defining a local class that is only used in a single program, then to define the outwardly visible components so that it fits into that program is usually sufficient. On the other hand, global classes must be able to be used anywhere. Since the system must be able to guarantee any program using an object of a global class, it can recognize the data type of each interface parameter and then certain restrictions are applied at the time of defining the interface of a global class.

Defining Local Classes

Local classes consist of ABAP source code, where the ABAP statements CLASS...ENDCLASS are enclosed. A complete class definition consists of the following parts, a declaration part and, if required, an implementation part. It is found that the declaration part of a class . The new class is called the subclass of the class from which it is derived. The original class is called the superclass of the new class. It contains the same components as the superclass if you do not add any new declarations to the subclass. However, in the subclass only the public and protected components of the superclass are visible. The private components of the superclass are not visible though they exist in the subclass. You can declare private components in a subclass that have the same names as private components of the superclass. It is seen that each class works with its own private components. The another point that we note is that methods which a subclass inherits from a superclass use the private attributes of the superclass and not any private components of the subclass with the same names.

The subclass is an exact replica of the superclass if the superclass does not have any private visibility section. However, you can add a new component to the subclass because it allows you to turn the subclass into a specialized version of the superclass. If a subclass is itself the superclass of further classes, then you can introduce a new level of specialization.

Polymorphism

Reference variables are defined with reference to a superclass or an interface defined with reference to it can also contain references to any of its subclasses. A reference variable defined with reference to a superclass or an interface implemented by a superclass can contain references to instances of any of its subclasses, since subclasses contain all of the components of all of their superclasses and also convey that the interfaces of methods cannot be changed. In particular, you can define the target variable with reference to the generic class OBJECT.

Using the CREATE OBJECT statement, when you create an object and a reference variable typed with reference to a subclass then you can use the TY PE addition to which the reference in the reference variable will point.

A reference variable can be used by a static user to address the components visible to it in the superclass to which the reference variable refers. However, any specialization implemented in the subclass cannot be addressed by it.

Depending on the position in the inheritance tree at which the referenced object occurs, you can use a single reference variable to call different implementations of the method. This is possible only if you redefine an instance method in one or more subclasses. This concept is called polymorphism, in which different classes can have the same interface and, therefore, be addressed using reference variables with a single type.

Conclusion

Back To Top

I have explained object orientation which is such an important aspect in SAP. The discussion began with the features of Object Orientation and includes the runtime environment, the language extension, the classes and the class components. Apart from that I have also discussed for new first time readers event handling, inheritance encapsulation and polymorphism.

chk out the links below:

General Tutorial for OOPS :

https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/e8a1d690-0201-0010-b7ad-d9719a41...

Have a look at these links for OO ABAP.

http://www.sapgenie.com/abap/OO/

http://help.sap.com/saphelp_nw04/helpdata/en/c3/225b5654f411d194a60000e8353423/content.htm

http://www.esnips.com/doc/375fff1b-5a62-444d-8ec1-55508c308b17/prefinalppt.ppt

http://www.esnips.com/doc/2c76dc57-e74a-4539-a20e-29383317e804/OO-abap.pdf

http://www.esnips.com/doc/5c65b0dd-eddf-4512-8e32-ecd26735f0f2/prefinalppt.ppt

http://www.allsaplinks.com/

http://www.sapgenie.com/abap/controls/index.htm

http://www.esnips.com/doc/2c76dc57-e74a-4539-a20e-29383317e804/OO-abap.pdf