Navigation Design
29.5.2 Navigation Design
Once the WebApp architecture has been established and the components (pages, scripts, applets, and other processing functions) of the architecture have been iden- tified, the designer must define navigation pathways that enable a user to access
WebApp content and services. To accomplish this, the designer must (1) identify the semantics of navigation for different users of the site and (2) define the mechanics (syntax) of achieving the navigation.
A large WebApp will often have a variety of different user roles. For example, roles might be visitor, registered customer, or privileged user. Each of these roles can be asso- ciated with different levels of content access and different services. A visitor may have access to only limited content while a registered customer may have access to a much broader range of information and services. The semantics of navigation for each of these two roles would be different.
The WebApp designer creates a semantic navigation unit (SNU) for each goal asso- ciated with each user role [GNA99]. For example, a registered customer may have six different goals, all resulting in access to different information and services. A SNU is created for each goal. Gnaho and Larcher [GNA99] describe the SNU in the follow- ing way:
A SNU is composed of
The structure of an SNU is composed of a set of navigational sub-structures that we call
a set of navigational
ways of navigating (WoN). A WoN represents the best navigation way or path for users with
substructures called
certain profiles to achieve their desired goal or sub-goal. Therefore, the concept of WoN is
ways of navigating
associated to the concept of User Profile.
(WoN). The SNU represents a specific
The structure of a WoN is made out of a set of relevant navigational nodes (NN) con-
navigational goal for a nected by navigational links, including sometimes other SNUs. That means that SNUs may specific type of user.
themselves be aggregated to form a higher-level SNU, or may be nested to any depth. During the initial stages of navigation design, the WebApp structure (architecture and
components) is assessed to determine one or more WoN for each user goal. As noted,
a WoN identifies navigation nodes (e.g., Web pages) and then links that enable nav- igation between them. The WoN are then organized into SNUs. As design proceeds, the mechanics of each navigation link are identified. Among many possible options are text-based links, icons, buttons and switches, and graph- ical metaphors. The designer must choose navigation links that are appropriate for the content and consistent with the heuristics that lead to high-quality interface design.
In addition to choosing the mechanics of navigation, the designer should also establish appropriate navigation conventions and aids. For example, icons and graph- ical links should look “clickable” by beveling the edges to give the image a three- dimensional look. Audio or visual feedback should be designed to provide the user with an indication that a navigation option has been chosen. For text-based naviga- tion, color should be used to indicate navigation links and to provide an indication of links already traveled. These are but a few of dozens of design conventions that make navigation user-friendly. In addition to conventions, navigation aids such as site maps, tables of contents, indexes, search mechanisms, and dynamic help facil- ities should also be designed at this time.
CHAPTER 29
WEB ENGINEERING
Parts
» The Concurrent Development Model
» SUMMARY Software engineering is a discipline that integrates process, methods, and tools for
» PEOPLE In a study published by the IEEE [CUR88], the engineering vice presidents of three
» THE PROCESS The generic phases that characterize the software process—definition, development,
» THE PROJECT In order to manage a successful software project, we must understand what can go
» METRICS IN THE PROCESS AND PROJECT DOMAINS
» Extended Function Point Metrics
» METRICS FOR SOFTWARE QUALITY
» INTEGRATING METRICS WITHIN THE SOFTWARE PROCESS
» METRICS FOR SMALL ORGANIZATIONS
» ESTABLISHING A SOFTWARE METRICS PROGRAM
» Obtaining Information Necessary for Scope
» An Example of LOC-Based Estimation
» QUALITY CONCEPTS 1 It has been said that no two snowflakes are alike. Certainly when we watch snow
» SUMMARY Software quality assurance is an umbrella activity that is applied at each step in the
» R diagram 1.4 <part-of> data model; data model <part-of> design specification;
» SYSTEM MODELING Every computer-based system can be modeled as an information transform using an
» Facilitated Application Specification Techniques
» Data Objects, Attributes, and Relationships
» Entity/Relationship Diagrams
» Hatley and Pirbhai Extensions
» Creating an Entity/Relationship Diagram
» SUMMARY Design is the technical kernel of software engineering. During design, progressive
» Data Modeling, Data Structures, Databases, and the Data Warehouse
» Data Design at the Component Level
» A Brief Taxonomy of Styles and Patterns
» Quantitative Guidance for Architectural Design
» Isolate the transform center by specifying incoming and outgoing
» SUMMARY Software architecture provides a holistic view of the system to be built. It depicts the
» The User Interface Design Process
» Defining Interface Objects and Actions
» D E S I G N E VA L U AT I O N
» Testing for Real-Time Systems
» Organizing for Software Testing
» Criteria for Completion of Testing
» The Transition to a Quantitative View
» The Attributes of Effective Software Metrics
» Architectural Design Metrics
» Component-Level Design Metrics
» SUMMARY Software metrics provide a quantitative way to assess the quality of internal product
» Encapsulation, Inheritance, and Polymorphism
» Identifying Classes and Objects
» The Common Process Framework for OO
» OO Project Metrics and Estimation
» Event Identification with Use-Cases
» SUMMARY Object-oriented analysis methods enable a software engineer to model a problem by
» Partitioning the Analysis Model
» Designing Algorithms and Data Structures
» Program Components and Interfaces
» SUMMARY Object-oriented design translates the OOA model of the real world into an
» Testing Surface Structure and Deep Structure
» Deficiencies of Less Formal Approaches 1
» What Makes Cleanroom Different?
» Design Refinement and Verification
» SUMMARY Cleanroom software engineering is a formal approach to software development that
» Structural Modeling and Structure Points
» Describing Reusable Components
» SUMMARY Component-based software engineering offers inherent benefits in software quality,
» Guidelines for Distributing Application Subsystems
» Middleware and Object Request Broker Architectures
» An Overview of a Design Approach
» Consider expert Web developer will create a complete design, but time and cost can be appropriate
» A Software Reengineering Process Model
» Reverse Engineering to Understand Data
» Forward Engineering for Client/Server Architectures
» SUMMARY Reengineering occurs at two different levels of abstraction. At the business level,
Show more