Select the Proper Kinds of Windows

1. Select the Proper Kinds of Windows

2. Human Task Switching • Types of Task Switching • Interruption • Need to find missing process or information • Human initiated rest • Effect of Task Switching • Cognitive attention lost • Cognitive load increases

3. Task Switching - Interruptions • For today’s Information Worker • interruptions are part of individual’s day • many people are interrupted 10 timesin each short task • interruptions require the individual to: • either search for their location in the task they are doing • or mentally record where they are in the task

4. Task Switching - Self initiated • People also interrupt their own task • many tasks are complex enough that humans lose track of where they are and restart them • many tasks are cognitively demanding and require mental rests • humans switch to reading their email or more routine tasks for this rest

5. Task Switching--Incomplete Preparation • People do not organize and plan their work for the week, day, hour except in a very general way • People carry out the next detailed part of their task based on the visual and auditory cues that are currently present in their task

6. Knowledge - Norman • In the head...and in the world • We behave precisely without precise knowledge • Information is in the world • Natural constraints are present • Cultural constraints are present • Precise memory is not required

7. Knowledge in the Head vs. in the World

8. Incomplete Preparation • Example • Cooking potatoes: after the potatoes have been washed, we use the visual cue of the washed potatoes with skins on to tell us we have to peel them • Similarly, when they are peeled, we know the next step is to cook them

9. Incomplete Preparation • Use of external cues to tell us where we are in the task is known as Situated Action • Reliance on situated action means that we often remember we need a crucial piece of information only in the middle of the task

10. Incomplete Preparation • For example, in cooking the potatoes, we may suddenly realize we need salt and have to run to the store to get salt • In short, we are not really forgetful; it is cognitively easier for us to do the task via situated action then to plan ahead • This leads to lots of task switching

11. Effect of Task Switching • Loss of task attention • Tasks require place-keepers for people to return to them at the point where they switched away • If the place-keepers are not available visually, they have to be maintained mentally • Even with visual place-keepers, there is some mental overhead in task switching

12. Task Switching Management • Because task switching is inherent in the social and psychological makeup of human work, humans have developed strategies for handling it • they lay out their work on a surface to be able to move from task to task • they create patterns in their layout to help them find and return to a particular task

13. How People Manage their Desktops • People have done studies of how people manage their desk in hopes of providing computer tools to support the task • People are either orderly or very messy, but the real issue here is that people have a visual sense of the layout of papers • They use this visual picture to help them find things

14. How People Manage their Desktops • People lay out items on their desk as reminders • People lay out items on their desk so they can do task switching • People lay out items on their desk so they can see the relationships among the items

15. Windows: Support forTask Switching • In the beginning, people had one application running on their computer at a time • Because we are constantly switching tasks, this became intolerable • exit program 1 • enter program 2 • exit program 2 • enter program 1 • Windows solve this problem

16. Windows: Our Virtual Messy Desk! • People use windows exactly like they use stacks of papers on their desks • But: task switching with windows is often like searching a very messy desk • built by programmers for programmers • windows appear in strange places and inconvenient sizes • like the QWERTY keyboard, we now mustlive with them

17. Chart-o-matic X Windows • Overview • Components • Presentation styles • Types • Organization • Operations

18. Some Uses of Windows • Support for human user • Provide knowledge in the world • Reflect the way people work • Presentation of information • Different levels, kinds, and sequences • Different sources • Performing more than one task • Reminding • Monitoring

19. Windows Components

20. Window Components--Win 98

21. Window Presentation Styles • Tiled • Single task activities • Tasks with little window manipulation • Novice or inexperienced users • Overlapping and cascading • Switching between tasks • Window manipulation needed • Expert or experienced users ? Disadvantages of each type

22. Tiled Limited screen size Open windows change size & position Windows get tiny Look crowded Less user control Overlapping More complex, possibly distracting Information gets hidden or lost Users don’t always recognize 3-D model Disadvantages of Presentation Styles

23. Types of Windows • Primary or Application • Secondary, Document, or Supplemental • Property Windows • Dialog Boxes • Modal or Modeless • Message Boxes • Palette Windows • Pop-Up Windows (e.g., paper clip guy)

24. Property Windows • Displays accessible properties of object • Information is grouped using tabbed pages

25. Dialog Boxes • Get additional information from user • Common dialogs • Open • Save • Print

26. Message Boxes • Provides information to the user • Standard types • Information • Warning • Critical error

27. Palette Windows • Presents a collection of controls-- graphical or pictorial • Mutually exclusive choices--like radio buttons • Palettes • Toolbars

28. Pop-Up Windows • Displays additional information • Most standard secondary window components omitted • Example: tooltips

29. Types of Windows • Single Document Interface (SDI) • Multiple Document Interface (MDI) • Workspaces • Workbooks • Projects

30. MDI Windows

31. Organizing Windows • Organize windows to support user tasks • Rather than organizing by features, functions, or ease of implementation • Minimize the number of windows needed to perform a task • Focus on common tasks

32. Sizing Windows • Large enough to • Contain expected information • Avoid hiding important information • Avoid crowding • Otherwise, as small as possible! • Text - about 12 lines • Alphanumeric - about 7 lines

33. Window Operations • General Guidelines • Focus on ease of use and learning • Less is more • Give users control / ability to tailor • Especially for overlapping windows! • Keyboard Control/Mouseless Operation Opening…Placement…Separation…Moving… Resizing…Shuffling…Closing

34. Limitations of Windows • Little research on window design/use • Hardware limitations • Human limitations