1. 1 Interaction Styles

2. 2 Introduction In order to get a system or a device to do something for us we need to be able to communicate/ interact with that system There are different was user can do this How do you communicate with your MP3 to get it to play the music you want to hear? How do you get a the snack or drink that you want from a vending machine?

3. Remember the coffee machine!! 3

4. 4 Interaction styles The choice of interaction style will depend on The type of task The user The environment It will also depend on the technology and the choice of input and output devices

5. 5 The Primary Styles of Interaction Q & A Menu selection Form fill-in Command language Direct manipulation Natural language/Anthropomorphic

6. 6 Q & A Simple interaction style Users respond to series of questions Input is usually Y/N or a particular single input Print whole document? No of pages to print? No of copies

7. 7

8. 8 Advantages of Q & A Easy to learn Good for novice or casual users Errors can be trapped User is led step by step through the task

9. 9 Disadvantages of Q & A Task has to be clearly defined and quite narrow Have limited functionality Not sophisticated

10. 10 Menu Selection metaphor Employs metaphor of restaurant menu Users Users read list of items; select appropriately according to task; apply syntax to indicate selection; confirm choice; initiate action; observe effect Designers Designers may need to use careful task analysis to ensure all functions supported conveniently, and that terminology is appropriate and consistent in use

11. 11 Advantages and Disadvantages of Menus Advantages shortens learning curve reduces keystrokes structures decision-making permits use of dialogue-management tools allows easy support of error-handling Disadvantages imposes danger of deep-nested menu hierarchies may slow frequent users consumes screen “real estate” requires rapid display rate

12. 12 Menus Activity How might you structure a menu for the following options Print in a WP application Selecting a patient from a medical database To find the price of a particular car

13. Menu Task – Looking 4 Picture Gallery Memory Card Images Video Clips Music More Options 13

14. Images Empty 14

15. Memory Card Dictionary Pre defMusic Pre dev Videos Themes More 15

16. More Themes Graphics Tones Recordings Received Files 16

17. ??? Graphics Tones Games Collection More Images 17

18. I will try Images Yipee! Worth waiting for?? 18

19. 19 Form Fill-in metaphor Paper forms can be used as metaphor (or indeed, template) Users Users see a display of related fields; move a cursor among the fields, and enter data as appropriate Designers Designers need to ensure that users understand field labels, appropriate values and the data-entry method, and are capable of responding to error messages - some user training may be necessary

20. Form Fill 20

21. 21 Form Fill Activity List 10 applications where you would consider using a form fill dialogue

22. 22 Advantages and Disadvantages of Form Fill-in Advantages simplifies data entry requires modest training makes assistance convenient permits use of form-management tools Disadvantages consumes screen “real estate”

23. 23 Form Fill Activity How can you minimise the risk of a user entering the date incorrectly in a date field? How can you make it clear to the user what the mandatory fields are? What do you think the task structure for getting an on-line car insurance quote should be

24. 24 Command Language metaphor Appropriate metaphor may be military parade ground! Users Users learn syntax; can express complex possibilities rapidly without reading distracting prompts Designers Designers must allow for high error-rates; diversity of possibilities and complexity of mapping from task to computer syntax is hard; user training is necessary

25. 25 Advantages and Disadvantages of Command Language Advantages flexible appeals to “power” users supports user-initiative convenient for creating user-defined macros Disadvantages poor error handling requires substantial training and memorisation

26. 26 Command Language activities For a travel agency airline reservation and enquiry system how might a command based dialogue system be utilised? Why do you think this style could be an advantage / disadvantage

27. 27 Anthropomorphic/Natural Language metaphor Utilises conversational metaphor Aims to interact in same way that humans interact with each other Aims to interact in same way that humans interact with each other Natural Language - Users speak or Natural Language - Users speak or enter natural language sentences; computer often seeks clarification before beginning task Anthropomorphic - Recognise gestures, facial expressions, eye movements Anthropomorphic - Recognise gestures, facial expressions, eye movements Designers Designers need to understand task domain to narrow range of interpretations to manageable level; design is extremely difficult

28. 28 Natural language What would be the advantages of using natural language for a train ticket enquiry system? What would be some of the disadvantages? List 3 applications where it could be a benefit

29. 29 Advantages and Disadvantages of Natural Language Advantages relieves burden of learning syntax Is natural – no need to learn -no training! Can be good for people with physical disabilities Disadvantages requires clarification dialogue may require more keystrokes/slow prone to errors may not show context is unpredictable Domain areas where it can be used are very limited

30. 30 Direct Manipulation Metaphor Metaphor is of a virtual world representing the “real world” Users Users point at visual representations of objects and actions, carry out tasks rapidly and see immediate results; keyboard control replaced by cursor-motion control devices Designers Designers need to choose appropriate icons and graphics to successfully “immerse” the user - minimal user training indicated

31. Direct Manipulation 31

32. 32 Advantages and Disadvantages of Direct Manipulation Advantages presents task concepts visually easy to learn easy to retain permits error avoidance encourages exploration permits high subjective satisfaction Disadvantages May be difficult for physically impaired Require graphics displays and pointing devices

33. 33 Shneiderman’s Eight Golden Rules of Dialogue Design 1. Strive for consistency 2. Enable frequent users to use shortcuts 3. Offer informative feedback 4. Design dialogues to yield closure 5. Offer simple error handling 6. Permit easy reversal of actions 7. Support internal locus of control 8. Reduce short-term memory load

34. 34 Menu-Selection & Form Fill-in Additional Guidelines

35. Menu selection design guidelines Semantic organisation logical grouping of options sensible, understandable, memorable menus must have logical grouping of options based on user’s task single menu is simplest, but options are few (in GUIs radio buttons or check boxes can be used) binary (Yes/No) menus are a possibility extended menus (multiple pages are more normal)

36. Extended menus Strategies for extended menus include multiple screens multiple screens accessed hierarchically scrollable “single” windows pull-down menus pull-down menus: lower levels invisible until accessed from a top menu bar pop-up menus pop-up menus: context-sensitive availability of option lists

37. Menu selection guidelines Use task semantics to group menu options Use “broad and shallow” options rather than “narrow and deep” Make items brief; show position by numbers, graphics or titles Use meaningful sequences of items Use consistent grammar, layout, terminology Provide short-cuts (e.g., “hot-key combinations) Allow jumps to previous menus

38. Form fill-in design Meaningful titles - dictated by task, not computer, semantics Comprehensible instructions brief, jargon-free instructions preferred Logical grouping and sequencing of fields close as possible to paper form “template” Visually appealing layout uniform spacing is better than crowded areas Familiar field-label names and order of entry left-to-right, top-to-bottom but with task logic in mind

39. Form fill-in: Error handling and feedback Error correction Error correction for individual characters and entire fields user should not be forced to “complete” data entry before backtracking to make corrections error-messageson-line help Clear error-messages and on-line help for invalid entries Optional Optional and compulsory fields clearly distinguished completion signal Clear completion signal avoid making completion automatic; explicit confirmation of “finish” is preferable