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Web Design WorkshopDIG 4104c

Lecture 2.5:

Requirements

J. Michael Moshell

University of Central Florida

Adapted from DIG3563. You may recognize it...!Ferrit.com.au.

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Tell 'em what you're gonna tell 'em

• concepts of requirements analysis

• Problems with requirements analysis

• A rubric and check-list

• JMM applies the rubric to a problem

• Your team applies the rubric to a practice problem

THEN WE: * state each team's problem succinctly

* your team is USER for another team

* you will draft & present reqs for them

Shingleberrysigns.com

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Classical Requirements Analysis

• The 'waterfall model' of software development:

A one-way flow of activities:

- figure out the requirements

- design the software

- build the software

- test it

- deliver it to the client

- fix bugs and maintain the software

What's wrong with that model?

Aynsof.com

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Problems with the Waterfall

What's wrong with that model?

• Customers don't really know what they need

• Requirements change as

- customers learn from prototypes

- customers' activities and needs change

• Constraints change as the true costs emerge

Result: "Design" and "Build" are not really separate processes!

Aynsof.com

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So, what to do about it?

We still have to start with requirements

But we will revisit them and revise them

during the building process

USER CENTERED DESIGN is ITERATIVE DESIGN

• Stakeholder identification

• User Stories and Use Cases

• Requirements lists (and problems with them)

• Measurable Goals and Acceptance Procedures

• Mock-ups and Prototypes

Lrn.usace.army.mil

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So, what to do about it?

* Project Description – 20 to 50 words

• Stakeholder identification

• User Stories and Use Cases

• Requirements lists (and problems with them)

• Measurable Goals and Acceptance Procedures

(Used to ask for mock-ups. Proved to be useless,

at this stage.)

Lrn.usace.army.mil

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My Example:Conference Management

* A small business (owned by my wife)

Manages conference registration

Project Description:

An easy-to-use online system that will allow a conference manager

to display nametag samples from all previous conferences, so

as to quickly select a layout and inform the IT manager to

use or modify it for an upcoming conference.

Web.cs.gc.suny.edu

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Stakeholder Identification

"Who cares?". More formally -

• Who is going to use this system?

• Who is going to have to take care of it?

• Who is going to be affected by it?

• Who will benefit, directly or indirectly?

• Who will lose, directly or indirectly?

• Who is affected in some indefinite way?

Truelegends.coml

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User Stories

Short enough to write on a 3" x 5" card.

As a <role>, I want <goal/desire>.

Example:

As a conference manager, I want to be able to look

At the nametags from previous conferences so

We can reuse the designs or get ideas from them.

Cs.rochester.edul

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User Stories

As the IT manager, I want to know which nametag

the boss wishes me to use, and any changes she wants

me to make, as well as the name of

the upcoming conference that will use it.

Cs.rochester.edul

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What is a Use Case?

• It is a single KIND of interaction with a system

• We define Use Cases to help design User Interfaces

• The Use Case does NOT explain. It just identifies –

The actor or actors

The activity

and, in limited, cases, extensions of the activity.

UC is the first step in Analyzing the User Story

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Use Cases(Written out in text)

Conference manager:

(1) enter conference name and see badges

from all years of that conference

(2) select a badge;

(3) Write comments about it (requests for changes)

(3) transfer a badge from the registration

system to the badge display system

www.wikipedia.org

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Use Cases(Written out in text)

IT manager:

(1) Edit the badge's layout, according to

instructions received from conference manager

www.wikipedia.org

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Use Case DiagramsExplain WHO does WHAT and with WHOM.

(Does not explain HOW it is done.)Cs.rochester.edul

Conference

Manager

See Badges

Select Badge

Transfer Badge IT

ManagerEdit Badge

Annotate Badge

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Use Case DiagramsExplain WHO does WHAT and with WHOM.

(Does not explain HOW it is done.)

Example: Convenience Market

Customer

Buy Gas

Buy Lotto Ticket

Count Inventory

Clerk

AnotherUse Case DiagramExample

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Where are the Details?

• Specify them in your Requirements List (Next Topic)

((Be clear about what you require your system to do,

because you’ll have to IMPLEMENT IT!))

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Use Case Diagrams

More Examples

atlas.kennesaw.edu

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Use Case Diagrams

More Examples

Sometimes

the 'actors'

are not

human,

but software or hardware

As in this example ("Central computer")

tigris.org

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Use Case Diagrams

More

Examples

visual-paradigm.com

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Use Case Diagrams

More

Examples

Note

SUBSET

relations

between

user types.

We don’t

need to do this, in our course. visual-paradigm.com

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Use Case Diagrams

Examples with

the <extend>

and

<include>

relationships.

You will NOT

need these in

this course.

www.modernanalyst.com

<include>

<extend>

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Mother

Buy food

Cook Food

ChildServe Dinner

Eat Dinner

Child

NOT A Use Case Diagram!

Why not? It contains a sequence of activities, like a flowchart.

Use Case Diagrams are JUST about "who does what, with whom" ... not HOW!

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Requirements Lists

* Dangerous, if they are taken as a "contract"

- because of a false sense of mutual understanding

("We agree on the words, but not on what they mean.")

Lots of effort may go into meeting a requirement which is

then discarded.

* Useful, if they can be amended as the process continues.

Lrn.usace.army.mil

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Requirements Lists

Example:

1.System will have a GUI with pull-down menus that list

associations, conferences and years. One, two or three

of these items may be specified. A little window will

show thumbnails of all the badges matching the choices.

2. Associations, conferences, years, are all controlled vocabularies.

Conference manager will be able to extend each vocabulary item

(option) by adding new values for that item.

3. Manager will be able to communicate the specifics of

the selected badge to the IT manager, together with

a note of any needed changes, for use in a new conference,

by clicking on a button.

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Measurable Goals

Examples:

1.Manager will be able to find any name badge for any

conference we ever managed, within 20 seconds of

beginning the search.

2.System will not consume more than 2* the amount of

disk storage required to store GIF images of badges.

Lrn.usace.army.mil

www.wikipedia.org

Mockups and Prototypes

Select Association

Select Conference

Select Year

2010

2009

2008

Pull-down

Menus

Show BadgeButton

Iterating the Process• I showed the prototype to the user

• She said "I want to see multiple badges at once,

side-by-side for comparison.I prepared a modified mockup.

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Iterating the Process

• She said "I don't want to have to add badges one-

by-one. Can I just select "All badges from the

Cat Fancier's Association?"

I added a "wild card" to each pulldown menu.

Etc, etc.

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Iterating the Process• I showed the next prototype to the user• She said "Cool. Now, how do I tell the IT

manager about a new conference?

+ As part of that, how do I add to a controlled

vocabulary, e. g. by adding an association?

My next step would be to create a new use

case, requirement list, measurable goal, mockup.

Then we build some small prototypes that actually WORK,

Show them to the user, get further feedback.

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Prepare a Project Descriptionexample: Puppiemakers.com

Our website helps owners of male and female dogs find appropriate breeding partners, negotiate contracts and carry out cooperative puppy ventures for mutual benefit. The site provides recommendations for veternarians and access to appropriate breed registries.

Build A Project Description for YOUR project, "for practice". (Doesn't have to be final)

In a couple of minutes you'll tell the class what it is.

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Homework before Monday

Install GIT on your personal laptophttp://git-scm.com/

PREPARE your Personal Notes/Ideas for your

team's discussion on Monday; I suggest

a personal "first draft" of the Requirements Document

(use Rubric as a check-list)

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Knowyourmeme.com

Homework before Wednesday

Read Study Guide 1 and 2

* Be prepared to do what the guide calls forIf YOU are called on, and unready, it'll cost you big-time points

• If you are ready,

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Knowyourmeme.com