CS 4963: UI Design

Interaction Design, Part 1

Today:• What is Interaction Design, anyways?• How do we do interaction design?– Fundamentals and Building Blocks– Heuristics and Patterns

• Next Interaction Design lesson:– Deliverables– Documentation

“Interaction Design (IxD) defines the structure and behavior of interactive systems. Interaction

Designers strive to create meaningful relationships between people and the products

and services that they use, from computers to mobile devices to appliances and beyond.”

—Interaction Design Association (IxDA)

“Interaction design defines workflows that support users’ goals and tasks, the affordances

through which digital products and services communicate their functionality and interactivity to users, the ways in which users can

interact with those affordances, products’ behaviors in response to user interactions, and the methods by which products indicate state changes. Good interaction

design facilitates people’s tasks and ensures that digital products are both learnable and usable by reducing complexity as much as possible, preventing user error, adhering to standards when appropriate, and through consistency

across an entire product or product line. Typical interaction design deliverables include specifications, wireframes, usage scenarios, and prototypes.”

—Pabini Gabriel-PetitUXMatters.com

“Interaction design defines workflows that support users’ goals and tasks, the affordances

through which digital products and services communicate their functionality and interactivity to users, the ways in which users can

interact with those affordances, products’ behaviors in response to user interactions, and the methods by which products indicate state changes. Good interaction

design facilitates people’s tasks and ensures that digital products are both learnable and usable by reducing complexity as much as possible, preventing user error, adhering to standards when appropriate, and through consistency

across an entire product or product line. Typical interaction design deliverables include specifications, wireframes, usage scenarios, and prototypes.”

—Pabini Gabriel-Petit

…call and response.

Call and response.

from http://www.flickr.com/photos/anirudhkoul/2045497777/

(YOU)

Call and response.

from http://www.flickr.com/photos/anirudhkoul/2045497777/

Sing it!

WHOOOOOA!!

WHOOOOOA!!

Call and response.

from http://www.flickr.com/photos/anirudhkoul/2045497777/

We love you!

Freebird! FREEEBIRD!

Encore! AAAAH! FIRE!!! THE DRUMMER’S HAIR IS ON FIRE!

Yeah!!We’ll play another song as

soon as I extinguish the drummer.

“Interaction is acting on the world and receiving feedback from the world.” Interaction design is defining how do you [as a user]…- do? Affordances?- feel? Interactivity?- know? Mental models?—Bill Verplank (helped develop Xerox Star, establish IDII)

from designinginteractions.com

How is IxD done?• Building blocks– Affordances (and common controls)– States (and Transitions …context!)– Feedback (Behavior)

• Heuristics– General approaches– Human-Computer Interaction methods– Interaction Design Patterns

BUILDING BLOCKS

Affordances

from http://www.flickr.com/photos/arrrika/315335846/

from http://www.flickr.com/photos/smig44/2690249520/

Affordances + Constraints => Mappings

Common Controls

from http://www.flickr.com/photos/brook/5259347/

from http://www.flickr.com/photos/tonyjcase/2759363747/

?

Feedback

from http://www.flickr.com/photos/24thcentury/2381462463/

from http://www.flickr.com/photos/rachelfordjames/2397592716/

vs.

States • You’re CS students. You

know what states are.• Help your user know

what state the system is in

• Helps with mental map• Prevents mistakes

from http://www.flickr.com/photos/tonyjcase/2375636885/

“Experience is a temporal phenomenon.

... You need to have as much detail in the transitions as

in the states, otherwise you’re going to get it wrong.”

—Bill Buxton Microsoft Research

Transitions!

from http://www.flickr.com/photos/ultimorollo/sets/72157615748412640/

???(these are

the same animal?!?)

State transition revisited

GENERAL HEURISTICS

Make it easy to recover.• First, do no harm!• General rule:

• If it’s something that’s not undoable—a destructive action—, warn.

Be consistent.• Make common

things behave in the same way

• Make behavior predictable

from http://www.youtube.com/watch?v=yUSIpRo13oc On Android phones, the long press always brings up a context menu (or at least, it should).

Consider the locus of attention.

• Where possible, put actions for the task at hand at the locus of attention, put other things at the periphery.

from Flickr: edit action is right there.

Remember this, from slide 18?

Be conversational.

• People like it.

from GMailfrom Google

Reader

from Google Search

Level of interaction?• Some things

you want to be interactive, some you don’t.

• Many times, the user just wants to get to Point B

from http://www.worrydream.com/MagicInk/

(Note that the UI on the right takes less clicks AND makes more information

visible.)

Don’t annoy.

from http://www.flickr.com/photos/anirudhkoul/2045497777/

Hey, do you want to allow this

app to run as administrator? I

know you said yes the last 20

times, but…

Beep! Beep! BEEEEEEEP!

Have I told you about this great deal on SPAM? Earn points!

ARE YOU REEEALLY SURE YOU WANT

TO SAVE THIS FILE? REALLY??

JUST LET ME SING FERGOODNESSSAKES

Surface simplicity, hide complexity.

• More choices make people …unhappier?

HUMAN-COMPUTER INTERACTION

(There is a whole course on this, yes.)

Hick’s Law

• More choices visible? Faster...

Time (in msec) = a + b log (n+1)

2

Remember this from slide 14?

n Log2 (n+1)2 1.5849634 2.3219288 3.169925

16 4.087463

Fitts’ Law!

• Larger targets, targets on screen edges are easier to hit

Time (in msec) = a + b log (D / S + 1)

2

DS

GOMS Keystroke-Level Model

• Way to measure efficiency of an interface

Letter Time (s) Meaning

K 0.2 pressing a Key or buttonP 1.1 Pointing to position (moving

cursor)H 0.4 Homing: switching input

contextM 1.35 Mentally preparing for next

stepR ??? waiting for computer to

Respond

Example: MKKKKKKKMHPK = 1.35 + 0.2*7 + 1.35 + 0.4 + 1.1 + 0.2 = 13.9 sec

Human Interface Guidelines

• On top of all this, everyone has their own HIGs and UI Guidelines

• (Helps with consistency)

INTERACTION DESIGN PATTERNS

Not just for breakfast anymore.

Patterns

• People have done this before• Codified best practices

from Chris Messina’s Flickr collection linked in

the notes of this slide

Summary• Interaction design is crafting the

behavior of your software/app/system.

• It’s call-and-response, feedback to action.

• Affordances, constraints, mental models…

• …and designing the transitions between states.

• There are general rules, design patterns, and HCI methods that can help.

TO BE CONTINUED…

For next time…1. Take your first assignment’s BAD design,

and make two sketches (plus paragraph each) for how you might make it work better (better affordances, improved feedback, clearer state transitions).

For the first, keep the same hardware/controls, but relabel/change the interaction as needed. For the second, you can change anything.

2. Readings for next lesson: on the class blog.

Contact UsMatthias Shapiromatthias.shapiro@gmail.com

Jason AldermanJason.alderman@utah.edu

http://huah.net/cs4963