VCE IT Theory Slideshows

1
VCE IT Theory Slideshows
Problem Solving Methodology 2 DESIGN

• By Mark Kelly
• Vceit.com

2
Contents

• What needs designing?
• Design tools

3
Design...

• How the solution will work
• What interfaces and output will look like

4
Need to design

• Hardware needs
• Software needs
• Training and documentation requirements
• Procedures that need to be created or changed
• Evaluation criteria

5
Tools

• data dictionaries and data structure diagrams,
• input-process-output (IPO) charts,
• pseudocode,
• object descriptions.

6
Designing how bits of the solution fit together
e.g.

• Website pages, style sheets, scripts
• Database queries, forms, reports
• Program modules, procedures, functions.

7
Useful tools for this

• Website storyboards, site maps
• Database entity-relationship diagrams, data flow
  diagrams, structure charts,
• Multipurpose hierarchy charts, context diagrams,
  use cases.

8
Design

• Consider alternative designs
• More than one way to skin a cat
• Some designs may be technically great, but
  unacceptable because of constraints

9
Design

• Every solution has both pros and cons
• Whats acceptable to a developer might be
  impossible for the client
• Selecting a design strategy means achieving
  maximum pros with minimum cons
• What is a pro or con varies from client to client

10
Physical Design Tools

• These actually plan how to build a system
• They give instructions on what to do
• Physical data dictionaries (e.g.
  Customer_Surname is string, 25 characters)
• Data Flow Diagrams...

11
Physical Design Tools

• Storyboards
• Structure Charts
• IPO charts
• Layout diagrams / mockups
• Pseudocode

12
Designing appearances

• layout diagrams,
• annotated diagrams/mock ups
• prototypes

13
Designing the evaluation criteria

• What measures will be used to judge whether or
  not the solution requirements have been met?
• Should relate to the solution requirements
  identified in the analysis stages logical design.

14
Design

• Must be documented
• If successful, will lead to Development phase. If
  not, cancel the project.
• Is used as a strict instruction manual during the
  following phases, particularly during Development

15
VCE IT THEORY SLIDESHOWS

• By Mark Kelly
• vceit.com

These slideshows may be freely used, modified or
distributed by teachers and students anywhere on
the planet (but not elsewhere). They may NOT be
sold. They must NOT be redistributed if you
modify them.