Web Dynpro ABAP for Practitioners

479 Pages·2013·29.36 MB·English

by  Ulrich Gellert

Ulrich Gellert
Ana Daniela Cristea
Web Dynpro ABAP
for Practitioners
Second Edition
Web Dynpro ABAP for Practitioners
ThiSisaFMBlankPage
Ulrich Gellert (cid:129) Ana Daniela Cristea
Web Dynpro ABAP for
Practitioners
Second Edition
UlrichGellert AnaDanielaCristea
c/oS+PLIONAG c/oCellentAG
Heddesheim,Germany Karlsruhe,Germany
ISBN978-3-642-38246-8 ISBN978-3-642-38247-5(eBook)
DOI10.1007/978-3-642-38247-5
SpringerHeidelbergNewYorkDordrechtLondon
LibraryofCongressControlNumber:2013944196
©Springer-VerlagBerlinHeidelberg2010,2013
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Foreword
TakingAlbertEinstein’squoteasamotto—“Exampleisn’tanotherwaytoteach,
itistheonlywaytoteach”—ourtargetwastocreateabookforexplainingstepby
steptheWebDynproABAPtothereader.Assistedbypracticalexamples,youwill
learnmoreandmoreaboutWebDynproABAP,fromchaptertochapter.Moreover,
theconnectionswithotherareasarealsopointedoutbypracticalexamples.
In Chap. 1, we present the place and role of Web Dynpro within the SAP
NetWeaverplatform.So,westartwiththelayersoftheSAPNetWeaverplatform,
we continue with the importance of the Application Platform layer, and we con-
clude with the place and role of Web Dynpro (ABAP and Java) within the
ApplicationServerABAPand,respective,ApplicationServerJava.
Chapter2presentstheSAPEasyAccess,highlightingsomeaspectsfoundinour
everydaywork.So,weshowhowtochangethestandardsettings,howtoaddinthe
Favoriteslistthefrequentlyusedtransactions,andhowtocreateaShortcutonthe
Desktop.
InChap.3,wedescribethemodalitytocreatingaWebDynprocomponent.We
explain,throughexamples,alltheelementsofaview,andweshowyouhowtouse
theABAPDebuggertodiagnosetheapplication.
Chapter 4 gives attention to the ABAP Dictionary, where all the development
objects are created. These ones are the basis for all our examples. With this
knowledge,youwillbeabletoeasilycreateWebDynproapplications.
InChap.5,wepresentthecontextnodesandattributes,explainingtheirimpor-
tanceforWebDynpro.Weconsiderthepossibilitiestocreate,use,fillinwithdata,
andreadthecontents.
InChap.6,wegointodetailswithdatabinding,contextmapping,andinterface
methods. This chapter starts with the presentation of the mechanism used to
manipulate data between context attributes and user interface (UI) elements, the
mechanism called, inWeb Dynpro,“databinding.” We continue with the mecha-
nism of sharing data among the various controllers, which is realized by using
different variants of context mapping. Finally, we highlight the importance of the
interfacemethodsrequiredtoaccessthem“cross-component.”
v
vi Foreword
Chapter7coverstheviewcontrollermethods,beginningwithsomeexamplesof
Hook methods and ending with user-defined methods and event handler methods.
Each method is explained by an example. The main purpose of this chapter is to
present the role and the modality to use the various methods generated by the
Frameworkandthemodalitytorealizeourownmethods.
Chapter8illustratesthelayoutoftheUIelements.Here,wearegoingtopresent
thevarioustypesofexistentlayoutsandthemodalitytousethem,eitherinastatic
orinadynamicvariant.
In our largest chapter (Chap. 9), we describe in detail the user interface (UI)
elements. The UI elements that we can use in Web Dynpro ABAP are divided in
variouscategories.Inthischapter,wearegoingtopresentsomeoftheUIelements,
dividedinthecategoriesofaction,selection,layout,complex,graphic,andintegra-
tion. Each UI element will be illustrated by an example, showing the modality of
usingiteitherinastaticorinadynamicvariant.
Chapter10includesmessagesandexceptions.Westartwiththecreationofthe
necessary classes (Message Class, Exceptions Class, and Assistance Class). For
each of the two variants (messages and exceptions), we present two possible
implementation scenarios. Therefore, we start with the modality to create the
texts of messages and exceptions, and we conclude with the modality of using
themtocreatesolidapplicationsthatcatchexceptionsandinformtheuserthrough
messages.
Chapter 11 is about creating Multilanguage Applications on the levels of
interfaces and master data. So, the applications we realize are going to be easily
internationalized without it being necessary to recode them but only to translate
somecentralizedstrings.Forthis,wehavetorespectsomerules,asfollows:using
thetoolsofferedbytheABAPWorkbench,establishinganinitiallanguageforour
project, and avoiding to enter language-specific texts in the codification of the
businesslogic.
InChap.12,wepresentseveralWebDynpromodels.Weshowyounotonlyhow
to use an Assistance Class, a Web Service, or a BAPI, but also how to create
multicomponent applications congruent with the MVC (Model View Controller)
designpattern.
Chapter13coverstheABAPListViewer(ALV)andtheSelectOptions(SOs).
WestartagainwithsimpleexamplesandbuildthemuptoanALVoutputconfigu-
rationincombinationwithSOs.
Chapter 14 is dedicated to the POWER lists. We will explain, through an
example, how we can use the Personal Object Work Entity Repository(POWER)
listtosearchwithSelectOptionsandtodisplayinALVtablescertaindatawithout
it being necessary to use the components Web Dynpro SALV_WD_TABLE and
WDR_SELECT_OPTIONS. We will also learn the main transactions we have to
usetocustomizethePOWERlist,wewillimplementtheso-calledfeederclass,and
wewillusethestandardWebDynprocomponentPOWL_UI_COMPtointegratea
POWER list into a self-created Web Dynpro component. In this chapter, we will
alsolearnhowtousethehistoryfunctiontobeabletoprotocolallthechangesmade
byauseronthedatabaserecords.
Foreword vii
Chapter 15 covers the creating of modal windows and external windows. In this
respect,wewillusethefourmethodsoftheinterfaceIF_WD_WINDOW_MANAGER,
creatinganexampleforeachmethod.Wewillbeginwiththecreationofsimpledialog
boxesthatcontainonlytext,thencreatepop-upwindowsthatcontainUIelements,use
an external Web Dynpro component to create a modal window, and finally create
externalwindows.
Chapter 16 presents through an example the way we can use the Web Dynpro
applicationparametersandSharedObjectstocommunicatebetweenaWebDynpro
ABAPapplicationandaBSP(BusinessServerPages)application.Incasewehave
totransmit,betweenthetwotechnologies,datathatarenotsensitive,wecanusethe
WebDynproapplicationparameters.Incasewetransmitsensitivedata,ordatanot
suitable for transmission in a URL, or we need a large amount of data to be
transmitted, it is advisable to use Shared Objects. First of all, we will create a
verysimpleBSPapplicationthatwillcommunicatewithaWebDynproapplication
usingtheWebDynproapplicationparameters.Attheendofthepresentchapter,we
will use the Shared Objects to create the communication between a Web Dynpro
ABAPapplicationandaBSPapplication.Incaseyoudonotneedacommunication
withtheBSPtechnology,thischapterisalsointerestingbecauseitshowshowwe
canusetheWebDynproapplicationparametersandtheSharedObjects.
Chapter 17 mainly focuses on learning how to create and send Multilanguage
emailsbyusingWebDynproABAP.Here,wewillusealsothetransactionsSOST
(SAPconnectSendRequest)andSO10(SAPscriptStandardsText).
Chapter18 describes the integration ofWeb Dynproapplicationsinto the SAP
NetWeaver Portal. The portal offers many possibilities to create its content, from
wizards and templates to applications developed in Web Dynpro ABAP or Web
DynproJava.OurscopeistointegrateintotheportalacreatedWebDynproABAP
application.Afterthis,wecreateaWebDynprocomponentthatcansendaportal
event and another Web Dynpro component that can react to a portal event, and,
finally,weintegratethecreatedapplicationsintheportal.
Thenextchapter(Chap.19)isaboutWebDynproandauthorizations.Basedon
theRBAC(Role-BasedAccessControl)pattern,wearegoingtopresenttheSAPR/
3role-basedauthorizationmode.Accordingtoit,ausercandisposeofanumberof
roles,whichgrantstohim/hertheauthorizationtoaccesscertainresourcesfromthe
system.Inthisrespect,wewillcreatethedevelopmentobjectsrequiredtograntto
the user the possibility to access the records from a database, and we will use, in
Web Dynpro ABAP, the declaration AUTHORITYCHECK to verify the current
user’s authorization. At the end of this chapter, we will give some tips and tricks
from the praxis. We will show how to authorize the access to the Web Dynpro
applicationsandhowtogiveaccesstospecificpartsofanapplication.
In our last chapter (Chap. 20), we would like to show how the Mind Map can
help you to learn Web Dynpro ABAP easier and faster. We have created a Mind
Mapbasedonthesubjectspresentedinthisbook.FromtheUIelementstotheHook
methods and component reuse, this well-structured Mind Map helps us to learn
faster the Web Dynpro ABAP and, at the same time, to imprint in mind the main
elementsrequiredtolearnthistechnology.
viii Foreword
The examples in our book have been developed on a SAP system with SAP
NetWeaver 7.1 and Support Package 8. From SAP Developer Network (SDN)
(http://www.sdn.sap.com), you can download a free-of-charge SAP NetWeaver
Trial Version with ABAP and SAP GUI for testing. With this Trial Version, you
cancreatemostofourexercises.Youwillalsofindmostoftheconfigurationsteps
at SDN. To use the SAP interactive forms by Adobe, you need both NetWeaver
Trial Versions (ABAP and Java), because Adobe Document Service (ADS) is an
integralpartoftheSAPNetWeaverJavaversion.Additionally,youneedtheAdobe
LiveCycle Designer from the SAP Service Marketplace. The configuration steps
requiredinthiscaseareshownintheSAPPRESSbookSAPInteractiveFormsby
Adobe by Hauser et al. To be able to work with the portal, you need the SAP
NetWeaverJavaTrialVersion.IntheSAPPRESSbookDeveloper’sGuidetoSAP
NetWeaverPortalApplicationsbyBanneretal.,youwillfindallthesoftwareand
hardwarerequirements,alongwiththeconfigurationsteps.
The creation of a book takes time. Many discussions with students and
developers made us think about writing a practical book on the Web Dynpro
ABAP subject. The most important issue was to guide the reader step by step,
withpracticalexamples.Manyweekends,holidays,andeveningswereinvestedin
thisbook,andthepositivefeedbackofourcolleaguesalwaysgaveusnewenergy.
Acknowledgments
WewouldliketothankourproofreadersDieterSchmittandHeinz-JurgenGebhardt
(S+P LION AG); Memmer Manfred, Oliver Gilbert, and Thilo Klopfer (Cellent
AG);andMihaelaOsaci(PolytechnicUniversityofTimis¸oara–Romania).
Theiradvicesandcommentshelpedusalot.
UlrichGellertIwouldliketothankallmycolleaguesofS+PLIONAGfortheir
useful input during the project. I also would like to thank my father, Gerhard
Gellert,who unfortunately died too early. He introduced me to the world of ITin
1983,andourcompanycouldneverbecomewhatitiswithouthim.Specialthanks
gotomymother,GabrieleGellert.Shehasbeensupportingmeuntiltoday,andshe
is the heart of our company. Especially I would like to thank my lovely wife
CarmenandmychildrenAlexaandMarcfortheirsupportduringtheproject.
Dr. Ana Daniela Cristea I give special thanks to my colleagues from Cellent
AG, to Thomas Muschalik (NWCON Technology Consulting), and to S+P LION
AGfortheirgreatsupport.Takingthisopportunity,Iwouldliketothankthespecial
personswhoguidedmealongthewaytoadoctoraldegree,OctavianProsteanand
Mircea Vladutiu. Notto forget the people who encouraged me topublish my first
books and articles, Aron Poanta and Caius Panoiu, thanking them for their useful
advices. Last but not least, I would like to thank my family and friends who
supportedmewholeheartedly. Theygave methetimeIneededtobeoneofthose
whowrotethisbookforyou.
I would like to share the joy of creating this book with my mother, Sabina
Cristea. Unfortunately, she suddenly left us, before she could get a copy of this
book. Therefore, I dedicate my work in this book to my mother, a special person
whoImisseveryday.
ix