| Description | Overloading | Overriding |
| Achieved | It is achieved by having different methods with the same name and different signature | It is achieved by redefining the method in the sub class. The class is originally defined in the super class. |
| Same | The methods names are the same. Only the signature varies. | The method definition (name) including the signature are similar. It is only redefined. But the implementation of the method is changed. |
| Relationship | The relationship is between the methods in the same class. | The relationship is between the methods in the super and sub class. |
| ABAP | It is not explicitly supported in SAP ABAP. But it can be implicitly implemented through the concept of OPTIONAL keyword in method definition. | This overriding can be explicitly implemented in SAP ABAP. The REDEFINITION keyword is used in the method definition of sub class. |
| Example | A movie can be dubbed in different languages. The title and the characters are similar. Only the parameters such as Dialogue Delivery are different. Thus the movie is overloaded in different languages. | A movie can be remaked. Its parameters are similar. But the storyline and its content can be changed according to the viewers. Thus the movies are redefined. |
Category: ABAP
How to set the column position using the class CL_SALV_COLUMNS_TABLE?
The column position in the ALV Display can be controlled using the set_column_position method of the class CL_SALV_COLUMNS_TABLE. There are two parameter used in the method call. The column name identifies the column to be positioned. The position parameter mentions the position of the column in ALV Display.
Let us look at the following example:
DATA lr_salv_columns_table TYPE REF TO cl_salv_columns_table.
lr_salv_columns_table = lr_alv_grid->get_columns ().
lr_salv_columns_table->set_column_position ( columnname = ‘CONTACT_ADDRESS’
position = 3).
What is the difference between data reference and object reference in SAP ABAP
| PARAMETER | DATA | OBJECT |
| DEFINITION | DATA lr_ref TYPE REF TO data. | DATA lr_object TYPE REF TO object. |
| CREATION | CREATE DATA lr_ref TYPE REF TO (‘ZIF_INSTANCE’). | CREATE OBJECT lr_object TYPE (‘ZCL_CLASS’). |
| DEREFERENCE | It can be dereferenced. The object or any value can be assigned to dereferenced reference variable. lr_ref->* = lr_object | Object references cannot be dereferenced. This notation ->* cannot be used. |
| CONVERSION OR CASTING | How to convert a value or an object in to a reference: it can be converted in the following two ways. lr_ref->* = value or object lr_ref = REF #(value/obj) | How to cast an object. lr_object2 = CAST zcl_object2( lr_object ). |
| USAGE | used to create data references | Used to create objects for classes. |
| ASSIGNMENT | An object or any value cannot be assigned to a data reference variable. It must be deferenced in order to assign a value. lr_ref->* = lr_object. lr_ref->* = ‘string_value’ | Only objects can be assigned. It can be assigned directly without dereference. DATA lr_object TYPE REF TO object. DATA lr_object2 TYPE REF TO object. CREATE OBJECT lr_object TYPE (‘ZCL_CLASS’). lr_object2 = lr_object. |
| POSSIBLE SYNTAX ERROR | As mentioned before, values cannot be assigned directly without dereference. For example: lr_ref = ‘String_value’. This line of code will result in the below Error. “The type of ‘lr_interface1’ cannot be converted to the type of ‘lr_ref’ | If the types of data objects are different, then it must be casted during the assignment. Otherwise you will get the below error. ‘The type of ‘lr_object’ cannot be converted to the type of ‘lr_object2’. |
How to create an object dynamically in SAP ABAP
Name of the class: ZTC_CHECK_CLS.
Name of the method: METHOD_ONE.
DATA lr_check_cls TYPE REF TO object.
CREATE OBJECT lr_check_cls TYPE (‘ZTC_CHECK_CLS’).
CALL METHOD (‘ZTC_CHECK_CLS’)->(‘METHOD_ONE’).
If the class ‘ZTC_CHECK_CLS’ is not available in your repository. it will throw a runtime error as the object is created only during the runtime.
How to rename columns in SAP ALV DISPLAY of type CL_SALV_COLUMNS_TABLE.
The columns can be renamed with the object of the class cl_salv_column_table. There are four methods available such as SET_SHORT_TEXT (), SET_MEDIUM_TEXT(), SET_LONG_TEXT and SET_TOOLTIP(). The method can be chosen based on our requirement of text length.
DATA lr_salv_columns_table TYPE REF TO cl_salv_columns_table.
DATA lr_salv_column_table TYPE REF TO cl_salv_column_table.
DATA lv_short_text TYPE scrtext_s.
DATA lv_medium_text TYPE scrtext_m.
DATA lv_long_text TYPE scrtext_l.
DATA lv_tip_text TYPE lvc_tip.
lr_salv_columns_table = lr_alv_grid -> get_columns ().
lr_salv_column_table ?= lr_salv_columns_table -> get_column(‘CONTACT_NAME’).
lv_short_text = ‘short_contact_name’.
lr_salv_column_table -> set_short_text (lv_short_text).
lv_medium_text = ‘medium_contact_name’.
lr_salv_column_table -> set_medium_text (lv_medium_text).
lv_long_text = ‘long_contact_name’.
lr_salv_column_table -> set_long_text (lv_long_text).
lv_tip_text = ‘tip_contact_name’.
lr_salv_column_table -> set_tooltip(lv_tip_text).
If you wish to force the ABAP execution to use the short text instead of other texts, then there is an easy way to achieve this. Just ignore assigning the medium and long text, then it automatically considers the short text. The other two text formats are ignored by default.
How to insert and delete column in SAP ALV Display of type CL_SALV_TABLE.
The column is inserted through the field catalog of the ALV Table. It is set during the method call FACTORY ().
Step1: Extend the structure either locally or globally through the Transaction SE11 with the additional field.
TYPES: BEGIN OF ty_contact.
INCLUDE STRUCTURE ztt_db_table2.
TYPES: contact_age TYPE ZDE_contact_age.
END OF ty_contact.
DATA lt_contact TYPE STANDARD TABLE OF ty_contact.
It is always recommended to use an unique Data element for the fields of the structure, so that the column heading text can be easily maintained.
Step2: Call the Factory() Method of class CL_SALV_TABLE
CALL METHOD cl_salv_table => factory
IMPORTING
r_salv_table = lr_alv_object
CHANGING
t_table = lt_contact.
Through the field catalog of the ALV Table, a new column can be inserted or deleted.
There is a method REMOVE_COLUMN() for the column class ‘CL_SALV_COLUMN_TABLE’. But it is protected. Therefore the inheritance is needed to remove the column.
How to hide the column in new SAP ALV Display of type CL_SALV_COLUMNS_TABLE
The column can be edited using the column object. The Column object can be retrieved from the get_columns( ) method of the ALV object.
Step1: Get the columns object from the ALV object.
DATA lr_columns TYPE REF TO cl_salv_columns_table.
Lr_columns = lr_alv_object->get_columns( ).
Step2: From the columns object, get the particular specific column object ‘CONTACT_ID’. The name mentioned in the structure must be used. Even if the displayed name in ALV output is different, please always use the name in the structure.
DATA lr_specific column TYPE REF TO cl_salv_column_table.
Lr_specific_column = lr_columns->get_column( ‘CONTACT_ID’ ).
Step3: Call the set_visible method of the column object to hide the column in ALV Display. Please set the abap_false value to the importing parameter.
Lr_specific_column->set_visible( abap_false ).
How to use events of class CL_SALV_EVENTS_TABLE in SAP ABAP ALV Display
The new ALV Display provides different events based on the class CL_SALV_EVENTS_TABLE. It is much lesser compared to the old ALV Display. The Events can be found in the ‘Events’ tab of the class.
Let us discuss about the following important Events of the class CL_SALV_EVENTS_TABLE.
| Events | Description |
| DOUBLE_CLICK | This event will be triggered, when the user double clicks. |
| LINK_CLICK | This event will be triggered, when the user clicks on Hotspot or Button. Parameters are Row and Column |
| ADDED_FUNCTION | The defined function will be triggered. The parameter is E_SALV_FUNCTION. |
The following steps are needed to facilitate an Event action.
- Define the Event handler
- Register the Event handler
- Definition of Event Handler
CLASS zcl_handler DEFINITION.
PUBLIC SECTION.
CLASS-METHODS: on_link_click FOR EVENT link_click OF cl_salv_events_table
IMPORTING row column.
ENDCLASS.
CLASS zcl_handler IMPLEMENTATION.
METHOD on_link_click.
FIELD-SYMBOLS <ls_contact> TYPE ztt_db_table2.
READ TABLE lt_contact INDEX row ASSIGNING <ls_contact>.
IF sy-subrc = 0 AND column = ‘CONTACT_ID’.
“” DETAILS OF THE CONTACT PERSON IS DISPLAYED.
ENDIF.
ENDMETHOD.
ENDCLASS.
- Register the Event Handler
START-OF-SELECTION.
DATA lr_salv_events_table TYPE REF TO cl_salv_events_table.
Lr_salv_events_table = lr_alv_grid->get_event( ).
SET HANDLER zcl_handler=>link_click FOR lr_salv_events_table.
How to insert functions to the Functions toolbar of new SAP ALV Display CL_SALV_TABLE
The new ALV Display based on the class CL_SALV_TABLE offers you the possibility to add a new function. It is completely based on the Display mode. In the container mode, the function is added through the functions object. In the complete mode, it is added through the GUI status for the Dynpro.
Adding functions in Container mode:
The Add_function( ) method of the functions object is used to insert functions to the functions toolbar.
DATA lr_functions_list TYPE REF TO cl_salv_functions_list.
lr_functions_list = lr_alv_object->get_functions( ).
lr_functions_list->set_all( ).
lr_functions_list->add_function( name = ‘SUM’ text = ‘SUM’ tooltip = ‘SUM’
position = if_salv_c_function_position=>right_of_salv_function ).
Adding functions in complete mode:
In order to insert a new function in complete mode, copy the GUI status SALV_TABLE_STANDARD in your report.
- Open the function group SALV_METADATA_STATUS through the transaction SE80. Right click on the GUI status SALV_TABLE_STANDARD.
- Select the copy from the options in order to copy the GUI status.
- Give the program name and a name for the copied GUI status in the popup window and finally confirm the entries.
- The ALV object must be able to recognize the newly added GUI-status. It is recognized through the set_screen_status method of the ALV object.
Lr_alv_object->set_screen_status( report = ‘ZALV_NEW_FUNCTION’ pfstatus = ‘SALV_TABLE_STANDARD’ set_functions = lr_alv_object->c_functions_all ).
The GUI status can be further adjusted to insert the new function code.
How to activate the functions Toolbar of new ALV Display CL_SALV_TABLE
By default, the function toolbar is not displayed in the new ALV Display. It must be activated. The functions object is retrieved from the ALV Object. In order to activate the complete function toolbar, the set_all( ) method of the function object must be called.
DATA lr_functions_list TYPE REF TO cl_salv_functions_list.
lr_functions_list = lr_alv_object->get_functions( ).
lr_functions->set_all( ).