Adding your own buttons to ALV toolbar_SAP ABAP Advanced Cookbook-QQ阅读男生武侠网

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Adding your own buttons to ALV toolbar

The standard ALV toolbar provides a number of useful functions. However, depending on the requirement, you may be asked to add new buttons to the ALV toolbar. This recipe will show how to add your own buttons to the ALV toolbar and then writing appropriate coding to be executed when the user presses the button.

We will add a new button saying View Summary to the toolbar. Upon clicking, the total number of displayed records will be shown (for purpose of illustration).

Getting ready

For creating your own toolbar buttons, we need to make a copy of the GUI status displayed in the original ALV program. We will then make changes to the copied status. Proceed as follows:

For finding out the program whose GUI status is currently being called, generate the output of the ALV program and then select the menu option System | Status.. On the dialog that appears, we will use the values shown in the Program (GUI) and GUI status fields. The GUI status being used is ALV_TABLE_STANDARD residing in the program having name SAPLSALV_METADATA_STATUS.
We will copy this GUI status from the respective standard SAP program into our program. This may be done by using transaction SE80.

In the next section, we will see how new buttons are added.

How to do it...

We will see how to add new buttons and adding appropriate coding. Proceed as follows.

Use transaction SE80 to see the various components of your program. The newly copied status SALV_TABLE_STANDARD is shown under the GUI Status node.
Double-click the GUI status name to display its contents in the right-hand pane. From the section of toolbar buttons, we will remove the INFO button item, as it is not needed, and add our own function SUMM having the display text View Summary, as shown in the following screenshot:
Next, we will call the method set_screen_status of the class cl_salv_table and pass it the name of our program SY-REPID and the newly created status SALV_TABLE_STANDARD.
We will then create a class by the name summbutton (we can also use the existing class for hotspot created in a previous Adding hotspots to columns recipe). In the definition, a static method on_button_press is defined that responds to the triggering of the ALV event added_function. The method has an importing parameter e_salv_function that provides the function code of the selected customer function.
Next, the implementation of the method is created. Within the on_button_press method, we check to see if the SUMM function button has been pressed. If found true, we then calculate the number of lines in the table IT_PA0008, then concatenate the line numbers with appropriate text and display in an information message.
Finally we use the SET HANDLER statement to link the static method on_button_press of the class newbutton with the events object myevents. This will make sure the clicking on the New button triggers the execution of the on_button_press method.

How it works...

Calling the set_screen_status method results in the display of our newly created GUI status having the button View Summary. The method is called in order to make sure that instead of the standard GUI status, our newly created GUI Status is shown.

The CL_SALV_EVENTS_TABLE class contains an ADDED_FUNCTION event that is raised when our added button is pressed.

We registered this event with the static method on_button_press of our class newbutton using SET HANDLER statement.

Upon clicking the View Summary button, the code of the on_button_press method is called. We make sure in the method that the code is run only when the function code supplied by importing variable e_salv_function contains SUMM. If that is the case, the number of lines determined in the internal table are displayed using a MESSAGE statement.

For adding icons in the toolbar button, refer to the SAP documentation at http://help.sap.com/saphelp_nw04/helpdata/en/d1/801d43454211d189710000e8322d00/frameset.htm.

There's more...

The work so far done looks fine, but has a small problem. Clicking on the View Summary button will give the entire set of rows in the internal table IT_PA0008, irrespective of taking into account any filter applied.

We will now refine the recipe in order to read the filters, the column names included on which the filters have been applied, and the selection options specifying the filter values. At the end, we will delete the rows from IT_PA0008 that do not adhere to the filter criteria (so that the row count is correct). The example may then be refined later for deletion of filters, and so on.

The code that will be added will be within the IF statement (checking the function code) just before the DESCRIBE statement. The code is divided into three parts:

First, we declare necessary variable pertaining to ALV filters. We then use the get_filters method in order to read the filter objects.
The get method of the cl_salv_filters class is then called in order to fetch the internal table myfilters_tab specifying the column names on which filter has been specified. The R_FILTER component of this table row is a reference to the class CL_SALV_FILTER, which contains the values, entered at the filter screen.
Next, a loop is run at this internal table and the details of the r_filter object are fetched.
We run a loop at the myfilters_tab method and get the filter conditions object for each column. The get_sign, get_option, get_low, and get_high methods of the class cl_SALV_SELOPT is used for getting the sign, option, low, and high values of the filter condition respectively. These are added to the range table of the final_range_struc. Finally, the final_range_struc contents are inserted into the internal table final_range_table. The purpose of this step is to form a final range table named final_range_table, which will provide us with the name of each column specified in the filter definition, along with the filter values in the form of range table.
As you can see the user had specified two fields ENDDA and UNAME in the filter criteria. For the UNAME field, two filter values are specified, that is, UNAME = HOLDERM and UNAME = STUDENT060.
We will keep the third step simple, and will run a loop at the final range table which will delete from the main IT_PA0008 internal table those records that violate any of the filter criteria.

Once this additional code is added, the internal table IT_PA0008 will take into account any applied filter. Thus, the correct values will be shown by the View Summary button.

The code shown may be written more efficiently and elegantly using field symbols. Since the table contains fewer entries and for the sake of simplicity, field symbols were not used.