Gui Design

1
Gui Design

• Taken from Gui Bloopers by Jeff Johnson

2
First Principles

• 1. Focus on the users and their tasks, not the
  technology.
• 2. Consider function first, presentation later.
• 3. Conform to the users view of the task.
• 4. Dont complicate the users task.
• 5. Promote learning.
• 6. Deliver information, not just data.
• 7. Design for responsiveness.
• 8. Try it out on users, then fix it!

3
Focus on the usersAnswer the following Questions.

• For whom is this product or service being
  designed? Who are the intended customers? Who
  are the intended users? Are the customers and the
  users the same people?
• What is the product or service for? What
  activity is it intended to support? What
  problems will it help users solve? What value
  will it provide?

4
More Questions

• What problems do the intended users have now?
  What do they like and disklike about the way they
  work now?
• What are the skills and knowledge of the intended
  users? Are they motivated to learn? How?
• How do users conceptualize and work with the data
  in their task domain?

5
And more

• What are the intended users preferred ways of
  working? How will the product or service fit
  into those ways? How will it change them?

6
Users

• Software should be designed neither FOR users nor
  BY them, but rather WITH them.

7
2. Consider Function First

• This does NOT mean Get the functionality
  designed and implemented first, and worry about
  the user interface later.
• It means consider the purpose, structure, and
  function of the user interface and of the
  software as a whole before considering the
  presentation the surface appearance of the
  user interface.
• The word function here does not mean
  implementation, it means role what does it do?

8
KISS

• Keep It Simple Stupid
• Keep it as simple as possible, but no simpler.

9
3. Conform to the users view

• Dont make users commit unnatural acts.
• Steps users have to perform to get what they want
  that have no obvious connection to their goal.
• Imposing arbitrary restrictions
• Limiting persons name to 16 characters
• Allowing table rows to be sorted by at most three
  columns
• Providing undo for only the last three actions
• Forcing all address book entries to specify a fax
  number even though some people dont have fax
  machines

10
Cont.

• Use the users vocabulary, not your own
• Keep the program internals inside the program.
• Find the correct point on the power/complexity
  trade-off
• Sensible defaults
• Templates or canned solutions
• Progressive disclosure
• Generic commands (create, copy, move, )
• Task specific design

11
4. Dont complicate the users task

• Common tasks should be easy.
• Support customization
• Provide wizzards
• Dont give users extra problems to solve.
• Tiff to gif conversion, etc.

12
5. Promote Learning

• Think outside-in not inside-out
• Dont design like you assume the users will
  automatically know what the developers intended.
• Often the cause of Textual Ambiguity

13
Textual Ambiguity

• Crowds Rushing to See Pope Trample 6 to death
• Drunk Gets Nine Months in Violin Case
• Vineland Couple to Take on Missionary Position
• Teacher Strikes Idle Kids
• British Left Waffles on Falkland Islands
• Iraqi Head Seeks Arms
• New Vaccine May Contain Rabies
• Two Soviet Ships Collide, One Dies
• The patient was at deaths door, but the doctor
  pulled him through!

14
Other Ambiguities

• Typographical Ambiguity
• DOIT
• Graphical Ambiguity
• In or out

15
6. Deliver Information not just data

• Design displays carefully get professional help.
• Visual order and user focus
• Match the medium
• Attention to detail
• The screen belongs to the user.
• Preserve display inertia
• Minimize what changes when responding to an action

16
7. Design for Responsiveness

• Responsive software keeps up with users even if
  it cant fulfill every request immediately.
• It provides enough feedback for users to see what
  they are doing.
• It lets users know when its busy and when its
  not.

17
Poor Responsiveness

• Delayed or nonexistent feedback for user actions.
• Time-consuming operations that block other
  activity and cannot be aborted.
• Providing no clue how long lengthy operations
  will take
• Periodically ignoring user input while performing
  internal housekeeping tasks

18
8. Try it out on users, then fix it!

• Test results can surprise even experienced
  designers.
• Schedule time to correct problems found by tests.
• Testing has two goals informational and social
• Find aspects of the user interface that cause
  problems
• Convince developers that there are problems