Technical Articles
Using Virtual Elements with CDS in Fiori elements
Overview
In this post you will learn, how we can use ‘READ_TEXT’ function for Fiori elements application. Consumption CDS is generating the Fiori elements application but sometimes we need Abap Logic calculation. (Calculate field values using Abap resources one of them read text belongs to material or orders etc.).
In this case, we can use the CDS with Virtual Element.
What are the Virtual Elements and Why we use that?
Sometimes when we make a report, we need calculations for fields and we can not easily make calculations with CDS so that their values can be calculated directly on SAP HANA. Virtual elements represent temporary fields in applications. They are defined consumption CDS view with annotations within the SELECT list. However, the field calculations display by Abap classes that implement the specific code exit interfaces provided for this purpose.
The code exit class for virtual elements. We should implement suitable interfaces according to the use case;
- Interface IF_SADL_EXIT_CALC_ELEMENT_READ
- Interface IF_SADL_EXIT_FILTER_TRANSFORM
- Interface IF_SADL_EXIT_SORT_TRANSFORM
You can find more information about Virtual Element with Sap standard documents link.
Implementation Steps:
- Use Eclipse for creating CDS View. Use Virtual element in CDS with annotations.
You can find more information about create the CDS View for beginners.
CDS View;
@AbapCatalog.sqlViewName: 'ZI_V_GOODPACK'
@AbapCatalog.compiler.compareFilter: true
@AbapCatalog.preserveKey: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'Goodpack Series No - Basic View'
@OData: { publish: true }
@UI.headerInfo:{ typeNamePlural: 'GoodPack'}
define view ZI_GOODPACK
as select from likp as l1
inner join lips as l2 on l2.vbeln = l1.vbeln and l2.pstyv = 'ZPAC'
left outer join kna1 as k1 on k1.kunnr = l1.kunnr
left outer join vbfa as v1 on v1.vbelv = l1.vbeln and v1.vbtyp_n = '8'
left outer join vttk as v2 on v2.tknum = l1.vbeln
left outer join /scdl/db_proch_o as t1 on t1.docno = l1.vbeln
left outer join /scwm/huref as t2 on t2.docid = t1.docid
left outer join /scwm/hu_ident as t3 on t3.guid_hu = t2.guid_hu and t3.idart = 'Y'
left outer join lips as l3 on l3.vbeln = l1.vbeln
left outer join vbrp as v4 on v4.vgbel = l1.vbeln and v4.vgpos = l3.posnr
left outer join vbrk as v5 on v5.vbeln = v4.vbeln and sfakn = ''
{
@UI: { lineItem: [ { position: 10, label: 'Delivery'} ]}
key l1.vbeln,
@UI.hidden: false
@UI.selectionField: [{ position: 10 }]
@Consumption.valueHelpDefinition:[{entity:{name:'ZI_VKORGSH',element:'vkorg'}}]
@Consumption.filter : { selectionType : #RANGE, multipleSelections : true, defaultValue : '1250'}
l1.vkorg,
@UI.hidden: false
@UI.selectionField: [{ position: 20 }]
@Consumption.valueHelpDefinition:[{entity:{name:'ZI_WERKSSH',element:'werks'}}]
l1.werks,
@UI: { lineItem: [ { position: 20, label: 'Customer'} ]}
@UI.selectionField: [{ position: 30 }]
@Consumption.valueHelpDefinition:[{entity:{name:'ZI_KUNNRSH',element:'kunnr'}}]
l1.kunnr,
@UI: { lineItem: [ { position: 30, label: 'Customer Name'} ]}
concat( concat( k1.name1, ' '), k1.name2 ) as name1,
@UI: { lineItem: [ { position: 40, label: 'Delivery Note'} ]}
l1.xblnr,
@UI: { lineItem: [ { position: 40, label: 'Container ID'} ]}
v2.signi,
@UI: { lineItem: [ { position: 50, label: 'Actual Goods Movement Date'} ]}
l1.wadat_ist,
@UI: { lineItem: [ { position: 60, label: 'Material Number'} ]}
l2.matnr,
@UI: { lineItem: [ { position: 70, label: 'Short text for sales order item'} ]}
l2.arktx,
@UI: { lineItem: [ { position: 80} ]}
v1.vbeln as vbfa_vbeln,
@UI: { lineItem: [ { position: 90} ]}
t4.konsimento_tarih,
@UI: { lineItem: [ { position: 100} ]}
t4.konsimento_no,
@UI: { lineItem: [ { position: 110, label: 'Virtual Element'} ]}
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ZCL_DEMO_CDS_CALC'
cast( '' as abap.char(255)) as note
}
group by
l1.vbeln,
l1.vkorg,
l1.werks,
l1.kunnr,
k1.name1,
k1.name2,
l1.xblnr,
l1.wadat_ist,
l2.matnr,
l2.arktx,
v1.vbeln,
v2.signi,
t2.guid_hu,
t3.huident,
t4.konsimento_tarih,
t4.konsimento_no
Define relationship with CDS, ODATA and Custom Class.
2. Create custom class and implement intarface ‘IF_SADL_EXIT_CALC_ELEMENT_READ’. Implement both methods ‘GET_CALCULATE_INFO’ and ‘CALCULATE’.
- Method GET_CALCULATION_INFO is used to provide the list of fields which is required for the calculation.
- Method CALCULATE is actual method where we implement the custom logic.
- Implementation Step 1 : We called custom class in CDS view.
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ZCL_DEMO_CDS_CALC'
cast( '' as abap.char(255)) as note
Use the CALCULATE method for utilizing ABAP resource.
3. Use SAP Web IDE for creating List Reporting App.
You can find detail information about List Reporting App.
Output
Conclusion
In this blog, we learn how we can utilize the CDS virtual elements. I welcome all suggestions for improvement or questions. Thanks for reading.
References
http://sapabapcentral.blogspot.com/2019/04/fiori-elements-utilizing-cds-with.html
https://blogs.sap.com/2019/04/26/fiori-elements-utilizing-cds-with-virtual-elements
Canan Özdemir.
Great Blog !
Thanks for sharing.
Can you provide the code of the method GET_CALCULATION_INFO please? Thank you.
Hello Sandra Rossi,
You can check the this links;
https://help.sap.com/viewer/cc0c305d2fab47bd808adcad3ca7ee9d/7.51.6/en-US/04e64a8ffffe49b8a8a5469796f397c0.html
https://help.sap.com/viewer/923180ddb98240829d935862025004d6/Cloud/en-US/c65942c284dd490a9c3791630d4d4e41.html
get_calculation_info: This method is called before the actual data retrieval.
It ensures that all the relevant elements that are needed for the calculation of the virtual element are selected.
I followed basic example and tried use to "GET_CALCULATION_INFO" method.
But ı want to say; ı wrote 'price' in "get_calculation_info" method but I could use without writing.
I am not sure about using this method.
CDS CODE;
@AbapCatalog.sqlViewName: 'ZDEMO_CDS_V_005'
@AbapCatalog.compiler.compareFilter: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'CDS to Test Access Control'
@OData: {
publish: true
}
define view ZDEMO_CDS_005
as select from sflight as a
inner join sflconnpos as b on a.carrid = b.carrid
{
key $session.user as MyName,
key a.carrid as MyFlightCarrier,
b.agencynum as MyAgencyNumber,
a.fldate,
a.connid,
@UI: { lineItem: [ { position: 110, label: 'Virtual Element'} ]}
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ABAP:ZCL_DEMO_CDS_CALC'
cast( '' as abap.char(255)) as note,
@Semantics.amount.currencyCode: 'CURRENCY'
CURRENCY_CONVERSION(
amount => price,
source_currency => currency,
target_currency => cast( 'EUR' as abap.cuky ),
exchange_rate_date => a.fldate,
error_handling => 'SET_TO_NULL' ) as price,
@Semantics.currencyCode: true
cast( 'EUR' as abap.cuky ) as currency
}
where a.carrid = 'AA' and a.fldate = '20170706'
ABAP CODE;
METHOD if_sadl_exit_calc_element_read~get_calculation_info.
LOOP AT it_requested_calc_elements ASSIGNING FIELD-SYMBOL(<fs_calc_element>).
CASE <fs_calc_element>.
WHEN 'NOTE'.
APPEND 'PRICE' TO et_requested_orig_elements.
ENDCASE.
ENDLOOP.
ENDMETHOD.
METHOD if_sadl_exit_calc_element_read~calculate.
DATA(lv_today) = cl_abap_context_info=>get_system_date( ).
DATA lt_original_data TYPE STANDARD TABLE OF ZDEMO_CDS_V_005 WITH DEFAULT KEY.
lt_original_data = CORRESPONDING #( it_original_data ).
LOOP AT lt_original_data ASSIGNING FIELD-SYMBOL(<fs_original_data>).
IF <fs_original_data>-price GT 1000.
<fs_original_data>-note = | High Price|.
ELSE.
<fs_original_data>-note = | Low Price|.
ENDIF.
ENDLOOP.
ct_calculated_data = CORRESPONDING #( lt_original_data ).
ENDMETHOD.
I was more looking for some code related to the code you have posted in your post but thank you. I guess the code related to your post should be something like that (in your example, the field NOTE is calculated based on input fields SPRAS and VBELN):
Hi Sandra Rossi
Your question really made me curious and I started reading the standard documentation, which is actually correct but doesn’t explain the scenario why it was required.
(Scenario: It will be properly utilized in case of $select query option is used in odata service to fetch limited fields and the SADL will not fetch the data for those fields that are not in the $select query and so the method “CALCULATE” will not have that data in those fields to perform the calculation).
Your code looks fine but you don’t need to pass “VBELN” to requested requested_orig_elements as VBELN will always be filled with value as it is a key field.
This doesn’t change anything & even passing it will not be a problem, it is just redundant. Just thought to share this information
Thanks,
Mahesh
Thank you for the check and confirmation! I'm adding the info in the code.
Thanks for the explanation in detail.
Great example showcasing the ABAP Virtual elements 🙂
small advise, please replace the "References" section link with the below link
https://blogs.sap.com/2019/04/26/fiori-elements-utilizing-cds-with-virtual-elements/
That reference link blog post is copy of the above SAP blog post.
Thanks,
Mahesh
Hello Mahesh Kumar Palavalli,
Thank you for advice, if I saw this block I added it as a reference. I will added link.
Best regards.
Canan Özdemir.
Hello Canan,
Thank you for sharing a useful and great article.
That is a feature i just discovered, i wish i had known it before, could have helped in past projects, thanks for the share, great feature 🙂
Hi Canan,
Great blog with great explanation.
I have question, in this blog you are using virtual element to display data from the back end to the report in FIORI. My question is, is it possible to use virtual element to hold data input by user, in the form for example, and then post to SAP?
Regards,
Tj
Hello Tjarliman Rusadi,
Thank you for comment. I tried to answer the question as far as I understand.
Can you explain much more hold data input by user ?
We created Abap class and implemented IF_SADL_EXIT_CALC_ELEMENT_READ fo using Virtual Elements.
It is exit and call automaticly when you run report.
* If you create a form and send data to SAP with button;
you should use different class. You have 2 options for List Report;
1- You can create button and BOPF business object action in CDS view and give action name for button press event.
In this case your class created automaticly with action and you can write to code.
@UI.lineItem:
[
{ type: #FOR_ACTION, position: 2, dataAction: 'BOPF:ZACTIONTEST', label: 'Testt' }
]
2- You can create extention button and call your custom oData Service.
* When push to search button for display table's data and in that time If you want to save table's data you can use Virtual Elements class.
if it is independent of this, you should use a new class.
Best regards.
Canan Özdemir.
Hi Canan,
Thanks for replying. Really sorry it's been a while replying to you.
To your question about 'hold user's input data' in the form.
Actually, i have a list report application of material master, and the source data is from MARA table, etc. Based on that table i created CDS, and web service based on that CDS was created.
This app has the capabilities of create data as well with draft capabilities, so user can enter data in a form and save it by clicking standard button, and save those data into a custom table.
But now, user want to input some additonal data in the form, and these data is not exist in the std table which I chose to be as based table for my CDS (MARA, etc).
So my questiom is, how can I add those additional fields in my CDS (or in my web servive) as they dont exist in any tables?. Can I use this virtual element concept to add these fields especially in the form so user can enter values to it, and then later save it into a custom table.
Hopefully it is clear to you.
Thanks
Tj
Hi Tjarliman Rusadi,
I created CDS view and added field that field does not exist any table and When ı activated cds view, automatically it added draft table.
Also if ı change this field, new value save by draft table but ıf ı want to save my data to database table ı used draft class and method name is "COPY_DRAFT_TO_ACTIVE_ENTITY" for save my data. I want to share picture but ı can not loaded sorry.
you can find draft class: ( Business object overview -> go to the root node )
you can check this link :
https://blogs.sap.com/2019/01/09/abap-programming-model-for-sap-fiori-draft-based-for-non-guid-keys-much-more../
Best regards.
Canan Özdemir.
Hi Canan,
Sorry for late reply.
"I created CDS view and added field that field does not exist any table and When ı activated cds view, automatically it added draft table."
Could you pls. tell me how to add that field in the CDS view?
Are you using the same annotation like you mentioned above like
Hi Tjarliman Rusadi,
Yes, you can use like that.
cast( '' as abap.char(255)) as note
Ragards,
Canan Özdemir.
Great Blog
This is very useful.
Thanks for sharing.
Helpful.
Nice Blog.
Good info. Thanks for sharing !!
Vijay
Hi Canan , nice blog. Just wanted to know, if we can reuse this class between multiple independent CDS views?
Hello Shubhangi Pandey,
1- We can see entity name in GET_CALCULATION_INFO method. For example we can check entity name.
2- I couldn’t find separated parameter in CALCULATION method. If you have to use same class for two CDS you can use one column for parameter in table. You can send default parameter and read it in method. This is just idea.
3- You can create two differents class for each CDS. I think, it can be best method.
Ragards,
Canan Özdemir.
The performance of the example could be improved by calling function READ_TEXT_TABLE.
LOOP ... CALL FUNCTION 'READ_TEXT' ... ENDLOOP is causing lots of small queries on STX* tables which are more bundled with READ_TEXT_TABLE.
See SAP Note 2261311 for details.
Hi Canan,
Excellent Blog, Thanks for sharing.
I have a doubt, can we use virtual elements in extend of standard CDS view: C_MAINTOBJBREAKDOWNQUERY_CDS, and I have tried, but I am getting errors.
Thanks
Rana
Thanks for sharing this blog! I have a doubt about the use of Virtual Elements... Can be used with analytics.query view annotation for display their content in multidimensional reports of S/4HANA?
Hi Jorge
Any luck on the same?
Thanks
Kanika
Thanks for sharing the details. I tried a simple example but it seems to come out blank :
BASIC
Consumption :
Odata service
Odata Service : Blank ??
ABap Class
Can I ask if Virtual Elements are only supported when using "@OData.publish: true" ??????
I have an OData service where the CDS was imported as a Business Entity in SADL and the code behind the virtual elements is not executed.
Thank You
Hi,
Nice Blog. Thanks for sharing.
I have a question. Are the virtual elements will work on analytical query CDS?
I have tried but didn't see any difference even class method is not executed.
Thanks,
Bhargava
No virtual elements do not work with Analytical CDS. The class and method will not be called and you can see this in debug.
Hi
if virtual elements dont work for analytical CDS . Is there any option to pull virtual column in analytical CDS.
Hi,
Issue in Using Virtual Elements in ABAP CDS in using Analytics query Annotation
1. Created a ABAP CDS Views "ZACCOUNTING" which i am fetching the Data from the tables and it is @Analytics.dataCategory: #CUBE and also added the below Virtual element where it has call the CLASS ZCL_BRF_NEW_VALUE . Please find the detail code down
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ABAP:ZCL_BRF_NEW_VALUE'
cast( '' as abap.char(250)) as NewValue
2. Now Created Consumption view ZNALYTICAL fetching the data from the ZACCOUNTING which created in step 1 and now in this I added the @Analytics.query: true and @Analytics.dataExtraction.enabled: true
3.I had registered the ODATA of the ZNALYTICAL in the tcode: /iwnd/maint_service tcode
4.When i try to execute the OData Service and it is not calling the CLASS 'ZCL_BRF_NEW_VALUE'.
But if I had not use the @Analytics.query related Annotations in the CONSUMPTION view then it is calling the class 'ZCL_BRF_NEW_VALUE'..
Could you please tell me any approach is there to call a CLASS 'ZCL_BRF_NEW_VALUE'. even if use @Analytics.query related Annotations
1)CUBE View
@AbapCatalog.sqlViewName: 'ZBKPF'
@AbapCatalog.compiler.compareFilter: true
@AbapCatalog.preserveKey: true
@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'Accounting Document Header'
@Analytics.dataCategory: #CUBE
define view ZACCOUNTING as select from bkpf as SO left outer join bseg as SOI on SO.bukrs = SOI.bukrs and
SO.belnr = SOI.belnr and SO.gjahr = SO.gjahr {
key SO.belnr,
key SO.bukrs,
key SO.gjahr,
key SOI.buzei,
SO.blart,
SOI.dmbtr,
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ABAP:ZCL_BRF_NEW_VALUE'
cast( '' as abap.char(250)) as NewValue
}
2) Consumption View
@AbapCatalog.sqlViewName: 'ZACCOUNT'
@AbapCatalog.compiler.compareFilter: true
@AbapCatalog.preserveKey: true
@AccessControl.authorizationCheck: #NOT_REQUIRED
@EndUserText.label: 'ANALTICAL'
@Analytics.query: true
@VDM.viewType: #CONSUMPTION
@Analytics.dataExtraction.enabled: true
@OData.publish: true
@UI.selectionPresentationVariant: [{
qualifier: 'KPIWeightByCountry',
presentationVariantQualifier: 'KPIWeightByCountry',
selectionVariantQualifier: 'KPIWeightByCountry'
},{
qualifier: 'Default',
presentationVariantQualifier: 'Default',
selectionVariantQualifier: 'Default'
}]
@UI.presentationVariant: [{
qualifier: 'KPIWeightByCountry',
text: 'KPI: Amount per Country',
visualizations: [{
type: #AS_CHART,
qualifier: 'AmountByCompany'
},{
type: #AS_DATAPOINT,
qualifier: 'dmbtr'
}]
},{
qualifier: 'LineItemByYear',
text: 'Filter: LineItem by Year',
visualizations: [{
type: #AS_CHART,
qualifier: 'ChartBookingsByYear'
}]
},{
qualifier: 'Default',
visualizations: [{
type: #AS_CHART,
qualifier: 'ChartDefault'
}]
}]
@UI.selectionVariant: [{
qualifier: 'KPIWeightByCountry',
text: 'Default'
},{
qualifier: 'Default',
text: 'Default'
}]
@UI.chart: [{
qualifier: 'AmountByCompany',
chartType: #COLUMN,
dimensions: [ 'bukrs' ],
measures: [ 'dmbtr' ],
dimensionAttributes: [{
dimension: 'bukrs',
role: #CATEGORY
}],
measureAttributes: [{
measure: 'dmbtr',
role: #AXIS_1
}]
},{
qualifier: 'ChartBookingsByYear',
chartType: #DONUT,
dimensions: [ 'gjahr' ],
measures: [ 'buzei' ],
dimensionAttributes: [{
dimension: 'gjahr',
role: #CATEGORY
}],
measureAttributes: [{
measure: 'buzei',
role: #AXIS_1
}]
},{
qualifier: 'ChartDefault',
chartType: #COLUMN,
dimensions: [ 'gjahr', 'belnr' ],
measures: [ 'buzei' ],
dimensionAttributes: [{
dimension: 'gjahr',
role: #SERIES
},{
dimension: 'belnr',
role: #CATEGORY
}],
measureAttributes: [{
measure: 'buzei',
role: #AXIS_1
}]
}]
define view ZNALYTICAL as select from ZACCOUNTING {
@AnalyticsDetails.query.display: #KEY_TEXT
@UI.lineItem.position: 10
key belnr as DocumentNumber,
@AnalyticsDetails.query.display: #KEY_TEXT
key bukrs as CompanyCode,
@UI.selectionField.position: 10
key gjahr as FiscalYear,
@UI.lineItem.position: 20
key buzei as LineItem,
@UI.lineItem.position: 30
blart as DocumentType,
@UI.dataPoint.title: 'Amount'
@UI.lineItem.position: 40
dmbtr as Amount,
@UI.lineItem.position: 50
NewValue
}
Hi,
virtual elements not working for analytical CDS . Is there any option to pull virtual column in analytical CDS.
Please Suggest any alternative.
Thanks
Hi Durga Prasanth Vemula,
I have never tried it for analytical CDS so I don't know any answer sorry for this.
Best Regards,
Canan Özdemir.
Hi Canan,
How it_original_data get the data?
can we debug method from cds view ?
Thanks,
Ajit
Hi,
Is this IF_SADL_EXIT_FILTER_TRANSFORM work with the Draft enabled entity? I mean virtual element using @ObjectModel.filter.transformedBy: 'ABAP: ClassName' but BO is draft enabled.
gives this error: Draft entity &1: Virtual element &2 has no calculation exit
Any solution to this question? I am getting the same error in my use case.
You have to implement @ObjectModel.virtualElementCalculatedBy: 'ABAP:Class_name1' also along with @ObjectModel.filter.transformedBy: 'ABAP:Class_name2' for draft BO.
After this, it worked for me.
Great, thank you!
How did you implement the two classes?
Hi, Implement the different interfaces to the different classes.
Yes I did. I get another error in my 'transformed by' class because I try to filter on my new calulated virtual element from my first class. Any tips on how to make that work?
Hello Jennifer,
I tried like this on cds view. It works when you push the Go button.
@UI.lineItem.position: 80
@UI.lineItem.label:'Virtual Element Text'
@UI.identification: [{
position: 80,
label:'Virtual Element Text'
}]
@ObjectModel.virtualElement: true
@ObjectModel.virtualElementCalculatedBy: 'ABAP:ZCL_DEMO_VIRTUALELEMENT_CALC'
@Search.defaultSearchElement: true
@Search.fuzzinessThreshold: 0.8
@EndUserText.label: 'Note'
@UI: {
selectionField: [{position: 5}]
}
@ObjectModel.filter.transformedBy: 'ABAP:ZCL_DEMO_FILTER_TRANSFORM_CALC'
SalesOrderHeader.note,
Hello Chandra,
Great answer thank you for sharing. I tried same example, it works.
Best Regards,
Canan
Hi Canan,
Thanks for the great blog! I have implemented and I am able to display the read text.
i would like to check though if there is a maximum number of characters for the virtual element? 1024? is there any documentation about this?
Also for the formatting, is there a way for the columns to be displayed as how it is typed in the READ_TEXT?
Regards,
Charles
Hello Fang,
You can try use "FormattedText" for displaying READ_TEXT.
<m:FormattedText htmlText="{......}"/>
Best Regards,
Canan
Hello Canan,
But in order for us to do this, does this mean we have to customize the XML screen? Meaning the screen will no longer be standard?
Regards,
Charles
Hello Charles,
I did not diplay READ_TEXT columns to be displayed as how it is typed in the table but I displayed it on smart form using FormattedText. This smart form was custom form, not standard as you said.
Maybe you can try create extention field in your standard app.
Best Regards,
Canan
Are there any limitations
can we use Virtual Element for Field 1 and Aggregation for another field 2 in lower or upper layers
I am getting error, I have a base view with a virtual element for field A and in the consumption layer for another field B used aggregation annotation while activating oData getting error while generating metadata by frame work
Error - "Calculated elements not allowed in analytical views"
Hi Canan Özdemir
thank you for sharing above information.
Just a quick query, is there any performance degradation if we use Virtual Elements to calculate field value on the fly? Because the calculation logic will be at ABAP Layer(Presentation layer) and not in DB Layer. So, I want to know is it good practise to use Virtual Element or it should be used at extreme scenarios.
Kindly clarify.
Regards,
Prince
If the function takes some parameters, how to implement that? I am trying to use the UKM_COMMTS_BUPA_DISPLAY function in CDS to get the credit exposure value, but can't solve it.
What about input field? I want to get this virtual element as an input field.