SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Stella981
• 阅读 795

Part1 – how to test odata service generated by CDS view
Part2 – what objects are automatically generate after you activate one CDS view
Part3 – how is view source in Eclipse converted to ABAP view in the backend
Part4 – how does annotation @OData.publish work
Part5 – how to create CDS view which supports navigation in OData service
Part6 – consume table function in CDS view
Part7 – unveil the secret of @ObjectModel.readOnly
Part8 – this blog
Part9 – cube view and query view
Part10 – How does CDS view key user extensibility work in S4/HANA
Part11 – CDS view test double framework
Part12 – CDS view source code count tool
Part13 – CDS view authorization
During my recent CDS view explore I have experienced several ways of CDS view annotation declaration or generation. I list them in this blog for study purpose.

Approach 1: developer does not declaration explicitly, but backend generates automatically

Take this field for example:

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

I do not declare any display format on this field. It has DATS data type in the backend.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

When you publish this CDS view as OData service and check its metadata response, you can find the annotation “sap:display-format=Date” is automatically added. Who adds it?

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Answer: it is added here. Backend framework will automatically add corresponding annotation according to the data type of exposed field.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Approach 2: developer adds one style of annotation, and backend framework detects such annotation, and do some conversion

One example of this kind of approach can already be found from tutorial 7 – unveil the secret of @ObjectModel.readOnly

In that tutorial I explained how the annotation defined by developer (@ObjectModel.readOnly: true ) is converted by backend framework into sap:updatable = false.

@ObjectModel.readOnly: true
Z_i_Order_View.posting_date
We can also look into another example. We have use the following annotation “@Consumption.valueHelp: ‘_statusfixedvalue’ ” to assign a value help to field txt04:
@Consumption.valueHelp: ‘_statusfixedvalue’
Z_i_Order_View.txt04,
When framework has scanned the annotation in line 47, it will set flag lv_consumption_vh as true.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Base on the fact whether the assigned value help is a consumption or foreign key value help, different element name are put to internal table lt_param_display and finally all the left annotation necessary for value help is generated by framework:

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

And this picture below explains where does each field in metadata response come from. The logic in method _add_value_help is very useful as it teaches us how to create necessary annotation via ABAP code, which we will use later.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Approach 3: developer adds necessary annotation via ABAP code

If you would like to build a drop down list based on a CDS view field like the status field below,

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

it is not just enough to use the annotation “Consumption.valueHelp” in CDS view source code – you would just get a drop down list with technical code of status value displayed. Instead, you must tell Smart template framework to display status description text in drop down list.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

In order to archieve it, you must add the following ABAP code in DEFINE method of the MPC_EXT class of your OData service, to tell the framework that the text property for “status_code” is “status_text” by annotation. The usage of such coding to create annotation by ABAP code is learned from method _add_value_help mentioned in approach 2.

lo_txt_property = model->get_entity_type( 'Z_C_Status_FixedvalueType' )->get_property( 'status_code' ).

lo_txt_property->set_value_list( /iwbep/if_mgw_odata_property=>gcs_value_list_type_property-fixed_values ).

lo_text_anno = lo_txt_property->/iwbep/if_mgw_odata_annotatabl~create_annotation( 'sap' ).

lo_text_anno->add( iv_key = 'text' iv_value = 'status_text').

For details please refer to this blog How to build a drop down list using Smart template + CDS view

Approach 4: developer adds UI related annotation in CDS view which are consumed by UI5 SmartTemplate

All UI related annotation which could be inserted into CDS view source code could be found from SAP help.

Those UI annotations will not be converted by ABAP backend:

@UI.identification: [ { position: 10 } ]
Z_i_Order_View.posting_date

All UI related annotations could be retrieved via the url below:

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

And in the runtime, Smart-template also uses this very url to retrieve UI annotations so that it can know what styles of UI control the annotated CDS view field must be rendered as.

SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

Conclusion

For approach 1 & 2, they sometimes look mysterious as everything happens under the hood. Fortunately we are in ABAP world and we can debug everything to clarify what confuses us by ourselves

要获取更多Jerry的原创文章,请关注公众号"汪子熙":
SAP CDS view自学教程之八:SAP Fiori Elements里不同类型的annotation

本文分享 CSDN - 汪子熙。
如有侵权,请联系 support@oschina.cn 删除。
本文参与“OSC源创计划”,欢迎正在阅读的你也加入,一起分享。

点赞
收藏
评论区
推荐文章
blmius blmius
3年前
MySQL:[Err] 1292 - Incorrect datetime value: ‘0000-00-00 00:00:00‘ for column ‘CREATE_TIME‘ at row 1
文章目录问题用navicat导入数据时,报错:原因这是因为当前的MySQL不支持datetime为0的情况。解决修改sql\mode:sql\mode:SQLMode定义了MySQL应支持的SQL语法、数据校验等,这样可以更容易地在不同的环境中使用MySQL。全局s
皕杰报表之UUID
​在我们用皕杰报表工具设计填报报表时,如何在新增行里自动增加id呢?能新增整数排序id吗?目前可以在新增行里自动增加id,但只能用uuid函数增加UUID编码,不能新增整数排序id。uuid函数说明:获取一个UUID,可以在填报表中用来创建数据ID语法:uuid()或uuid(sep)参数说明:sep布尔值,生成的uuid中是否包含分隔符'',缺省为
待兔 待兔
4个月前
手写Java HashMap源码
HashMap的使用教程HashMap的使用教程HashMap的使用教程HashMap的使用教程HashMap的使用教程22
Jacquelyn38 Jacquelyn38
3年前
2020年前端实用代码段,为你的工作保驾护航
有空的时候,自己总结了几个代码段,在开发中也经常使用,谢谢。1、使用解构获取json数据let jsonData  id: 1,status: "OK",data: 'a', 'b';let  id, status, data: number   jsonData;console.log(id, status, number )
Java修道之路,问鼎巅峰,我辈代码修仙法力齐天
<center<fontcolor00FF7Fsize5face"黑体"代码尽头谁为峰,一见秃头道成空。</font<center<fontcolor00FF00size5face"黑体"编程修真路破折,一步一劫渡飞升。</font众所周知,编程修真有八大境界:1.Javase练气筑基2.数据库结丹3.web前端元婴4.Jav
Wesley13 Wesley13
3年前
mysql设置时区
mysql设置时区mysql\_query("SETtime\_zone'8:00'")ordie('时区设置失败,请联系管理员!');中国在东8区所以加8方法二:selectcount(user\_id)asdevice,CONVERT\_TZ(FROM\_UNIXTIME(reg\_time),'08:00','0
Wesley13 Wesley13
3年前
00:Java简单了解
浅谈Java之概述Java是SUN(StanfordUniversityNetwork),斯坦福大学网络公司)1995年推出的一门高级编程语言。Java是一种面向Internet的编程语言。随着Java技术在web方面的不断成熟,已经成为Web应用程序的首选开发语言。Java是简单易学,完全面向对象,安全可靠,与平台无关的编程语言。
Stella981 Stella981
3年前
Django中Admin中的一些参数配置
设置在列表中显示的字段,id为django模型默认的主键list_display('id','name','sex','profession','email','qq','phone','status','create_time')设置在列表可编辑字段list_editable
Wesley13 Wesley13
3年前
MySQL部分从库上面因为大量的临时表tmp_table造成慢查询
背景描述Time:20190124T00:08:14.70572408:00User@Host:@Id:Schema:sentrymetaLast_errno:0Killed:0Query_time:0.315758Lock_
Python进阶者 Python进阶者
10个月前
Excel中这日期老是出来00:00:00,怎么用Pandas把这个去除
大家好,我是皮皮。一、前言前几天在Python白银交流群【上海新年人】问了一个Pandas数据筛选的问题。问题如下:这日期老是出来00:00:00,怎么把这个去除。二、实现过程后来【论草莓如何成为冻干莓】给了一个思路和代码如下:pd.toexcel之前把这