Interaction Styles

Direct Manipulation

Menu selection, Form Fillin, Dialog boxes

Command Languages, Natural Languages

Course 6, CMC, 07/10/03

07/10/03 HC6 2

Toward an Interaction Style• High concept definition

– functionality– goals– benefits

• Task analysis– users and tasks

• Choice of interaction style– easy to learn, to apply, to retain over time– relevant to users task

07/10/03 HC6 3

OAI model

07/10/03 HC6 4

Direct Manipulation: 3 integrated principles

• Continuous representation of objects and actions of interest with meaningful visual metaphors

• Physical actions or presses of labeled buttons instead of complex syntax

• Rapid incremental reversible operations whose effect on objects of interest is visible immediately

07/10/03 HC6 5

Visual Thinking and Icons• Commercial graphic designers,

semiotically oriented academics, data-visualization gurus

• Preferences vary by user and by task

• Icons or Text?

• How to design icons?

• Sound and Animation added?

07/10/03 HC6 6

Problems with Direct Manipulation

• Visual representations too large for screen, too detailed

• Visual representations without obvious meaning

• Misleading metaphors

• Shift hardware devices

07/10/03 HC6 7

Menu Selection• Effective: recognition

• Early systems (selection via keyboard)– full screen menus: numbered, textual

• Modern systems (selection by mouse clicks)– pull-down and pop-up menus– radio buttons and check boxes– embedded links– menu items: textual, graphic, auditory

07/10/03 HC6 8

Organization Menu Items

• Meaningful: Superiority categorical menu organization over alphabetical organization

• Menu structures: single menus; linear sequence of menus; strict tree structures; acyclic networks; cyclic networks

• Key to menu structure: task-related objects and actions

07/10/03 HC6 9

Single Menus• binary menus

• multiple-item menus

• multiple-selection menus (check boxes)

• pull-down and pop-up menus

• scrolling and two-dimensional menus

• alphasliders

• embedded links

• iconic menus, toolbars, palettes

07/10/03 HC6 10

Alphaslider

07/10/03 HC6 11

07/10/03 HC6 12

Embedded Links (example)Glosser

07/10/03 HC6 13

Tree Structures

07/10/03 HC6 14

Pull-down menu (example)

07/10/03 HC6 15

Pie menu (example)

07/10/03 HC6 16

Tree-Structured Menus: Problems

• overlapping categories

• extraneous items

• conflicting classifications

• unfamiliar jargon

• generic terms

• too many levels

• users loss of orientation

07/10/03 HC6 17

Suggested Rules• create task-related groups of logically

similar items• form groups that cover all possibilities• make sure that items ar nonoverlapping• use familiar terminology, but ensure that

items are distinct from one another• the fewer the levels, the greater the ease

of decision making• add menu map to help users stay oriented

07/10/03 HC6 18

Sequence of Item Presentation

• There is a task-related ordering– chronological– increasing/decreasing (number, length, volume,

temperature, … )

• There is no task-related ordering– alphabetic– grouping of related items– most frequently used first– most important first

07/10/03 HC6 19

Response Time & Display Rate

• Long response times

• Slow display rates• Use command

language• Greater memory

demands

• Short response times

• Rapid display rates• Use menu selection• Cues to elicit

recognition

07/10/03 HC6 20

Form Fillin• Many fields of data are necessary

• Some guidelines from practitioners:– meaningful title– comprehensible instructions– logical grouping and sequencing of fields– familiar field labels– error prevention, correction, messages– completion signal

• List- and Combo Boxes, Coded Fields

07/10/03 HC6 21

Dialog Boxes

• Combine Menu Selection and Form Fillin

• Additional concerns– consistency across all system dialog boxes– relationships with other items on screen

• Guidelines for internal layout and external relationships

07/10/03 HC6 22

Dialog Box (example)

07/10/03 HC6 23

Command Languages

• Strategies for command syntax– simple command set– command + argument(s): DELETE FILEA– command + option(s) + argument(s):

• PRINT/3, HQ FILEA• A0821DCALGA0300P

– hierarchical command structure• CREATE FILEA LOCPR1• DISPLAY DIR1 SCR2

07/10/03 HC6 24

Command Languages• meaningful structure

• consistent argument ordering

• keywords vs. Symbols• change all KO to OK vs. RS: /KO/, /OK/; *

• congruent hierarchical forms of commands• move robot forward vs. advance vs. go• move robot backward vs. retreat vs. Back

• naming and abbreviations

07/10/03 HC6 25

Natural Language in Computing

• Natural-language interaction– restricted to specific tasks

• \erase worksheet; \insert row; \total all columns

– annoying cursor movements from object to toolbar

• automatic speech for selecting painting tools

• Natural-language Queries

• Text-database Searching