Changing SAP data is more complex than reading it. The following should be noted:
- While we can also use direct SAP SQL calls for reading, writing back via direct table updates only makes sense for our own Z tables, while a direct update of SAP tables can destroy the logical consistency of the SAP system.
- To update SAP data, use the options offered by SAP, such as SAP BAPIs or "Call transaction using...", which both check the input data and perform the update using existing SAP functions.
- It is often necessary to lock the dialog data so that two users cannot start changing an object in parallel and overwrite each other's changes.
- Checking the input data before the update is discussed in Tutorial 4
As an example, we include the change of some fields of the customer address in our application. For this we first define a button within the display of the address, with which the user can switch to the change mode:
In the HTML file the button is defined as follows:
HTML<!-- Change address -->
<img src="../../../icons/edit.png"
style="width:32px; margin:8px; float:right"
onclick="S10Apply('to_change');"/>That is, we display a suitable png image, move it to the right side with "float:right" and execute the ABAP method "to_change" when clicking on it.
If the application is also intended to be a desktop application, we give the button a tooltip with the option title=, for example <img ... title="Change address" />:
In the ABAP method "to_change" we navigate to a new screen "change". Before that it is necessary
- To lock the object, i.e. to set an "enqueue" lock in SAP terminology
- to re-read the customer address
since it may be that another user has changed the address while we were on the display screen for a while. In change mode we must always display the actual data, otherwise when we "Save" we overwrite an intermediate change made by another user. So when transitioning to change mode, always lock first, then read again:
ABAP* to address change
method to_change.
* enqueue KNA1
enqueue( ).
* read data again
s10databaseread( ).
* to adress change
s10nextscreen( 'change').
endmethod.The SAP system contains generated function modules for locking objects; their names begin with "enqueue_". The easiest way to find out which enqueue module you need to call is to call the relevant SAP change transaction and then use SM12 to see which lock was created with your user name. A double click on the lock entry shows the technical properties and there the "Lock Object name":
In this case we see that the function module "ENQUEUE_EXKNA1" must be called to lock. In our ABAP method "enqueue" we issue a suitable error message if the object is currently locked. The user who has currently locked the object can be found in the system field "sy-msgv1" after calling the enqueue module.
ABAP* enqueue KNA1
method enqueue.
call function 'ENQUEUE_EXKNA1'
exporting
kunnr = kunnr
exceptions
others = 1.
if sy-subrc ne 0.
s10errormessage(
exporting
text = |Customer is currently being processed by user | && sy-msgv1 ).
endif.
endmethod.
If the customer is not locked, s10nextscreen( "change" ) will call the change screen "change":
The address fields are now ready for input and marked as mandatory. The country is selectable via a dropdown field and the functions "Check", "Save" and "Back" are available. The HTML file for this:
HTML
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type"
content="text/html; charset=utf-8">
<meta name="viewport"
content="width=400">
<link rel='stylesheet' type='text/css'
href='../../../style/s10.style.css'>
<link rel='stylesheet' type='text/css'
href='../../../style/custom.style.css'>
<script
src='../../synactiveS10/synactiveS10.java.js'>
</script>
<title>Customer information</title>
</head>
<body style="width: 100%; margin: 0px; padding: 0px;"
onload='init();'
class="colorscheme9">
<div class="headerarea"
style="width: 100%; padding: 10px;">
<b>
Address change customer
<span class='output'
type="text"
name='kunnr'>
</span>
</b>
<br />
<br />
<button type="button"
class="toolbarbutton"
onclick="S10Apply('check');">
Check
</button>
<button type="button"
class="toolbarbutton"
onclick="S10Apply('save');">
Save
</button>
<button type="button"
class="toolbarbutton"
onclick="S10Apply('change_to_display');">
Back
</button>
</div>
<div style="max-width: 800px">
<!-- Name 1 -->
<div class="infoblock2"
style="height: 50px">
<label class='label output'
name="name1"
for='name1'>
</label>
<br />
<input type="text"
class="input"
required
name="name1"
id="name1"
style="width: 300px;">
</div>
<br />
<!-- Street -->
<div class="infoblock2"
style="height: 50px">
<label class='label output'
name="stras"
for='stras'>
</label>
<br />
<input type="text"
class="input"
required
name="stras"
id="stras"
style="width: 300px;">
</div>
<br />
<!-- Postal code -->
<div class="infoblock"
style="width: 100px;
height: 50px;">
<label class='label output'
name="pstlz"
for='pstlz'>
</label>
<br />
<input type="text"
class="input"
required
name="pstlz"
id="pstlz"
style="width: 80px;">
</div>
<!-- City -->
<div class="infoblock2"
style="height: 50px">
<label class='label output'
name="ort01"
for='ort01'>
</label>
<br />
<input type="text"
class="input"
required
name="ort01"
id="ort01"
style="width: 300px;">
</div>
<!-- Country -->
<div class="infoblock2"
style="height: 50px;">
<label class='label output'
name='land1'
for='land1'>
</label>
<br />
<select size="1"
name='land1'
data-s10dropdownlist='land1@dropdownlist'
id='land1'
class='inputselect'
required
style='width: 240px;'>
</select>
</div>
</div>
</body>
</html>Some notes:
- In the header area we have inserted the customer number with
<span class='output' type="text" name='kunnr'></span>
- Then the three buttons with the ABAP methods "check", "save" and "change_to_display".
- The input fields each consist of a label and an input field. All input fields are marked with the option "required" as obligatory input.
- The country key is not a direct input, but a drop-down list, in HTML a <select> tag.
We implement "Check" and "Save" via the ABAP technique "Call transaction using...", which we use to execute the SAP transaction in the background, which then also performs all SAP checks.
For the user it then looks like this, for example::
For "Check", we just execute "Enter" instead of "Save" at the end; this way we get the original SAP error messages. To build the batch input session for XD02 we can use the "Recording Mode" in transaction SHDB:
We then convert the recording into ABAP coding by building a batch input session from the current input data:
ABAP
method save.
check_or_save( save = 'X' ).
endmethod.
method check.
check_or_save( save = 'N' ).
s10infomessage( 'Input data checked' ).
endmethod.
method check_or_save.
* bdc data
data:
bdcdatawa type bdcdata,
bdcdata type table of bdcdata.
* message table for call transaction
data:
messtabwa type bdcmsgcoll,
messtab type table of bdcmsgcoll.
* create bdc data
* screen 101
clear bdcdatawa.
bdcdatawa-program = 'SAPMF02D'.
bdcdatawa-dynpro = '0101'.
bdcdatawa-dynbegin = 'X'.
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'RF02D-KUNNR'.
bdcdatawa-fval = s10getuservalue( 'KUNNR' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'RF02D-D0110'.
bdcdatawa-fval = 'X'.
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'BDC_OKCODE'.
bdcdatawa-fval = '/0'.
append bdcdatawa to bdcdata.
* screen 110
clear bdcdatawa.
bdcdatawa-program = 'SAPMF02D'.
bdcdatawa-dynpro = '0110'.
bdcdatawa-dynbegin = 'X'.
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'KNA1-NAME1'.
bdcdatawa-fval = s10getuservalue( 'NAME1' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'KNA1-ORT01'.
bdcdatawa-fval = s10getuservalue( 'ORT01' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'KNA1-STRAS'.
bdcdatawa-fval = s10getuservalue( 'STRAS' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'KNA1-PSTLZ'.
bdcdatawa-fval = s10getuservalue( 'PSTLZ' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'KNA1-LAND1'.
bdcdatawa-fval = s10getuservalue( 'LAND1' ).
append bdcdatawa to bdcdata.
clear bdcdatawa.
bdcdatawa-fnam = 'BDC_OKCODE'.
if save = 'X'.
bdcdatawa-fval = '=UPDA'.
else.
bdcdatawa-fval = '/0'.
endif.
append bdcdatawa to bdcdata.
* dequeue, otherwise account is locked
dequeue( ).
call transaction 'XD02' with authority-check
using bdcdata
mode 'N'
update 'S'
messages into messtab.
* enqueue again
enqueue( ).
data: messagetext type string.
loop at messtab into messtabwa.
* get message text
message
id messtabwa-msgid type messtabwa-msgtyp number messtabwa-msgnr
with messtabwa-msgv1 messtabwa-msgv2 messtabwa-msgv3 messtabwa-msgv4
into messagetext.
case messtabwa-msgtyp.
when 'E' or 'A'.
* set focus for known input fields
case messtabwa-fldname.
when 'KNA1-LAND1'. s10setfocus( 'LAND1' ).
when 'KNA1-PSTLZ'. s10setfocus( 'PSTLZ' ).
endcase.
s10errormessage( messagetext ).
when others.
* final message after "save"
if save = 'X'.
s10infomessage( messagetext ).
endif.
endcase.
endloop.
endmethod.Please note:
- Set all input values in external format in the folder. For this we use the function s10getuservalue(), e.g. s10getuservalue( 'NAME1' ). This does not matter for the customer name, but it does for numbers (decimal point or comma), dates and special fields where a conversion exit is specified in the SAP system. So it is best to work generally with s10getuservalue().
- The process via "Call transaction using..." locks the corresponding object; we must therefore release our own lock before the call and set it again afterwards.
It is theoretically possible that exactly at the time between the removal of the lock and the "Call transaction using..." another user wants to change the same object and locks it. However, this is extremely unlikely, as the time period is very short, and would only have the effect that the user receives the error message "Object is locked by other user" when clicking "Save" or "Check". - When processing the batch input session in "Call transaction using...", select the synchronous update mode with the option update 'S'. Otherwise, in the event of delays in the SAP update task, a lock may run into an error after the call, as the update has not yet been completed and the object is therefore still locked.
- If the SAP system reports an error, for example the entry of a postcode with the wrong length, you will receive not only the error message but also the name of the field that triggered the error. You can then set the input focus to the corresponding field with s10setfocus() in the S10 application. The S10 error message is automatically displayed near the focus field.
- If you perform the "Save" function by calling a BAPI, no unlocking is necessary before the BAPI call, because the BAPIs do not lock the object themselves, but rely on the caller having already done so. After a BAPI call to save, do not forget to call "BAPI_TRANSACTION_COMMIT" afterwards, otherwise the changes will not take effect.
- The "check" function in BAPI calls can sometimes be switched on by a separate BAPI parameter that suppresses saving at the end. If this is not the case, call "BAPI_TRANSACTION_ROLLBACK" instead of "BAPI_TRANSACTION_COMMIT" at the end of "Check".
The implementation of the function "Back from change mode" is simple in principle: we unlock the object and set the next screen "display". At this point, however, be sure to re-read the data so that in the event of incorrect entries and then "Back", all fields are at the currently saved status.
ABAPmethod change_to_display.
* dequeue KNA1
dequeue( ).
* read data again
s10databaseread( ).
* next screen: display
s10nextscreen( 'display').
endmethod.