Transcript Menu Interfaces Benefits of menu’s: Learnability, memorability, error avoidance Minimize memory load Drawbacks: possible inefficiency hierarchical complexity (menu trees)

Menu Interfaces
Benefits of menu’s:
Learnability, memorability, error avoidance
Minimize memory load
Drawbacks:
possible inefficiency
hierarchical complexity (menu trees)
Menu Interfaces – Design Issues and
Choices
What kind of menu?
1-level v. hierarchical v. “linear”
Affordance of menu: how to activate/deactivate
pull down, pop-up, dropdown list
always present: list, toolbar, toolbox, radio buttons
appears automatically
1-level Pull-down Menu
2-level Hierarchical Menu
Old-style linear menu system
Select Database
1. Employee database
2. Customer database
3. Product database
4. Sales database
>> 1
Type number of desired selection and <Enter>
Select Function
1. Add a records
2. Delete records
3. Print report
>> 3
Type number of desired selection and <Enter>
Select Report Style
1. Print selected records
2. Print statistics
3. Print selected records and statistics
>>
Type number of desired selection and <Enter>
Menu Design Issues and Choices (cont.)
Number of items
items per menu = “breadth”
Number of active choices
Menu title names
Menu item names
Menu item ordering
Menu Design Issues and Choices (cont.)
Appearance
text v. iconic items v. both
horizontal v. vertical v “fast and vast”
Idioms:
selection list
check box
menu bar
radio buttons
drop-down selection list
toolbars
push buttons/hyperlinks
pie menus
Q. Are embedded links menu’s ??
A. Only if they are arranged in a list
Menu Design Issues and Choices(cont.)
Item Selection mechanism (affordance) by:
Mouse click
Drag and release (Macintosh)
Keyboard entry
- arrow cursors & <RET>
- Mnemonic letters & <RET>
- Other “shortcuts”
Affordance for Hierarchical Menu selection:
MouseDown
Mouse-over with pop-up levels (use of
DELAYS)
Efficiency of Menu’s
Response Time and Display Rate
The speed at which a user can move through menus may
determine their attractiveness as an interface mechanism.
User performance and preference favors broader, shallower
menus
Efficiency of Menu’s (cont.)
Menu shortcuts:
Alt-key opens menu
CTL or function key activates menu item
Menus with typeahead recommended when:
Menus are familiar
Response time/display rates are slow
BLT approach:
single-letter menus with typeahead leads to concatenation of
hierarchical menu selections into mnemonics.
Menu names or bookmarks/macros for direct access
Hierarchical Menus
Design Issues
Taxonomy design problem
Male, female
Animal, vegetable, mineral
Fonts, size, style, spacing
Depth versus Breadth - difficult trade-off
Depth v. Breadth Trade-off in Menu Design
Kiger (1984) grouped 64 menu items 6 ways:
8, 8 | 4, 4, 4 | 2, 2, 2, 2, 2, 2 | 4, 16 | 16, 4
22 subjects performed 16 searches.
Rated for speed, accuracy, preference.
2 X 6 was worst in all categories, 8 X 8 rated highly
Hierarchical Menus
Models of Menu Performance
Time for one selection:
T = k + c * log2b (b is breadth; k,c parameters representing
scan and selection time)
Total time = D * T where D is depth of tree = log b N
Hierarchical Menus
Models of Menu Performance (cont.)
Experiment with 4096 items:
16 per menu twice as fast as 2 per menu
Example 1: N = 4096, b = 16, D = 3
Predicted time for a search is 3 * (k + c * 4) or [3k + 12c]
Example 2: N = 4096, b = 4, D = 6
Predicted time for a search is 6 * (k + c * 2) or [6k + 12c]
c is time to visually search, k is mechanical overhead of
moving the mouse, clicking, etc.
Menu Design Guidelines
Task-related Grouping
Create groups of logically similar items
Form groups that cover all possibilities
Make sure that items are non-overlapping
Use familiar terminology, but ensure that items are distinct
from one another
Menu Design Guidelines (cont.)
Ordering Menu Items
The order of items in the menu is important, and should take
natural sequence into account when possible:
Time
Numeric ordering
Physical properties
When cases have no task-related orderings, the designer
must choose from such possibilities as:
Alphabetic sequence of terms
Grouping of related items
Most frequently used items first
Most important items first
Use horizontal bars to create within-menu grouping
Menu Design Guidelines (cont.)
Naming of Menu Items
Titles - For single menus, use a simple descriptive title.
For linear menus, use the exact same words in the higher-level
menu items as in the titles for the next lower-level
menu. E.g. if a menu item is called Business and Financial
Services, the next screen should have that phrase as its title.
Phrasing of menu items
Use familiar and consistent terminology
Ensure that items are distinct from one another
Use consistent and concise phrasing
Bring the keyword to the left
Menu Interfaces - Summary of Design Issues
Choose type of menus (simple, linear, tree structured)
Choose menu selection mechanism ( & shortcuts)
Grouping/organizing menu items
Taxonomy design for tree-structured menus
Depth v. breadth trade-off
Select names of menu choices
Order choices within each menu
Select menu titles