Constructing a Recursive and Loadable Web Dynpro Tree

 

In the following tutorial, you construct a recursive Web Dynpro tree that only loads its data when the user wants to see it.

The Task

This tutorial shows you how to use a performance-efficient recursive Web Dynpro tree. You insert a Web Dynpro Tree into a view and only fill the nodes and elements of the tree when the user expands the node.

In this tutorial, you simulate a file structure that is to be displayed in the form of a tree. A tree represents the exact structure as it exists in the context of the view at runtime. Since it is impossible to know how many subfolders the file structure has, the context must be constructed recursively. The recursive structure has the advantage that any number of subfolders can exist at runtime.

You also implement the selection of an entry in the tree. In this tutorial, you want to display the text of the selected entry in an input field.

You want the user interface of this Web application to have only one view. This view consists of a tree, a label, and an input field for displaying the selected element. Initially, you want a node of the tree to be selected and expanded.

 

 

Objectives

When you have completed the described procedure, you will be able to:

!	Use a context recursively
!	Implement a Web Dynpro tree that loads data
!	React to the selection of a tree node

 

Prerequisites

Systems, Installations, and Authorizations

·        The SAP NetWeaver Developer Studio is installed on your PC.

·        You have access to the SAP J2EE Engine.

Knowledge

·        Java programming language

·        Basic knowledge of programming of Web Dynpro applications

Next step:

Importing a Project Template