What is Web Dynpro?

We present the place and role of the Web Dynpro within the SAP NetWeaver platform. So, we start with the layers of the SAP NetWeaver platform, we continue with the importance of the Application Platform layer, and we conclude with the place and role of Web Dynpro (ABAP and Java) within the Application Server ABAP and, respective, Application Server Java.

As we can see, four layers are distinguished in this context: Application Platform, Process Integration, Information Integration and People Integration.

The Application Platform represents the technical basis of almost all the other SAP products. This is the reason why the Application Platform plays a central role in the SAP NetWeaver.

The Application Platform essentially offers two programming interfaces: ABAP and Java (J2EE). ABAP is the programming interface for Application Server (AS) ABAP and Java is the programming interface for AS Java.

TRANSACTIONS

GENERAL INTRODUCTION TO TRANSACTION

Transaction, in R/3 system is an operation that lets the user make necessary changes to the database. The entire R/3 system is nothing but set of business transaction. The data transfer from old system to SAP R/3 database, or modifying data, or deleting data, which is not required, is done through transaction.

For SAP system, Transaction is nothing but sequence of steps called as dialog steps and for user it is sequence of screens that appears one after the other depending upon the option he selects. The special transaction monitor called the SAP dispatcher handles the sequence of steps that takes place in any transaction. The main task of transaction is to update database table. The database table is not updated until a transaction is completed. All changes can be rolled back if the transaction has not finished.

SAP Easy Access 

Abstract This chapter presents the SAP Easy Access, highlighting some aspects found in our everyday work. So, we show how to change the standard settings, how to add in the Favorites list the frequently used transactions, and how to create a Shortcut on the Desktop.

SAP easy access starts automatically after logging-in into the SAP system. In the left side, we can see the user menu. Here are the functions the user needs to perform his tasks.

SAP easy access

Changing the SAP Easy Access

Designing a Web Dynpro Component

Abstract The present chapter is dedicated to the constitutive elements of a Web Dynpro ABAP component. Moreover, we show how to use the ABAP Debugger to execute, by line or by section, a Web Dynpro application, and how to use the new tool offered by ABAP Debugger to reach the context attributes values.

In order to develop a Web Dynpro ABAP component, we have to open the ABAP Workbench of the Application Server ABAP.To work with ABAP Workbench, we need an authorization as a developer or developer key, and for the SAP NetWeaver ABAP trial version we can use BCUSER, automatically registered as a developer.Web Dynpro is available with release SAP NetWeaver 2004s and later. After logging into AS ABAP, we can use the transaction SE80 to call the object navigator.

Object navigator

ABAP Dictionary

Abstract The following section details and describes the ABAP Dictionary.The main purpose of this chapter is to show how to realize all the development objects to be used in the future Web Dynpro applications.Therefore,we present not only the modality to create the various development objects in the ABAP Dictionary, but also the modality to use them in realizing Web Dynpro applications.

We can create development objects in ABAP Dictionary,by using the transaction SE11(ABAP Dictionary Maintenance) or the Object Navigator.

Development object with transaction SE11

Context Nodes and Attributes at Design Time

This chapter mainly focuses on the context nodes and attributes statically realized at design time. In this respect, we will explain not only the role and modality to create context nodes and attributes, but also the modality to access the values stored in the attributes of the nodes.

An attribute is a context entity that has certain properties and can be directly created in the root node CONTEXT, or as a child for another node. Usually, a node is used to group more attributes that belong together. In Fig.  we present a context example created in a view context.

A context node can have attributes or can hold other nodes, but a context attribute cannot have other attributes or nodes. We create a hierarchical arrangement that has, as the start point, the root node CONTEXT. This is automatically created when the controller is initialized and all the nodes and attributes we created are children of this root node.

Example of the structure of a View Context

Data Binding, Context Mapping and Interface Methods

This starts with the presentation of the mechanism used to manipulate data between the context attributes and UI elements, mechanism called,in Web Dynpro,“data binding”. We continue with the mechanism of sharing data among the various controllers, which is realized by using different variants of context mapping. Finally, we highlight the importance of the interface methods required to access them “cross-component”.

In the last chapter, we have created context nodes and attributes in the context view.A node or attribute can be created in each context. When we create an attribute in the context view, this value is visible only in this context view. The mechanism for sharing data among different controllers is known as “context mapping”. A context mapping can be internal, when the nodes we map are within the same component, and external, when the mapping is cross-components.

Data Binding

Each UI element has certain properties. With data binding, we define which node or attribute from the context will act as a data source for an UI element property. To exemplify the data binding mechanism, we create a component named Y_DATABINDING with a view named V_BIND and a window W_DEFAULT.