Midterm Exam, October 24th, 2000 Tuesday, October 24th, Human-Computer Interaction IT 113, 2 credits First trimester, both modules 2000/2001

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1 257 Midterm Exam, October 24th, Midterm Exam, October 24th, 2000 Tuesday, October 24th, 2000 Course Web page: sb.de/users/jameson/hci Human-Computer Interaction IT 113, 2 credits First trimester, both modules 2000/ Reminder of Instructions 2. A Walkthrough of S 3. Hypothetical Comments by the Designer of S 4. Writing of Final Exam Instructions Overall Question 258 Note These instructions are identical to those that were distributed in class, except for the final note about extra credit under "grading" Overall question The overall question to you is "What would you write in an message to this designer in order to help her better to understand the issues she s been thinking about?" You can offer Possible explanations of phenomena that the designer has observed (e.g. typical user difficulties) Suggestions as to how S might be improved

2 259 Instructions Goals Goals in formulating an answer 1. Say things that are useful and relevant to the issues that D has raised That is, don t just mention ideas from the book or your notes without making it clear why they are relevant to D s concerns 2. Show that you have learned something in this course That is, you must resist the temptation to express ideas that have no clear relationship to the material of this course, no matter how brilliant such ideas may be 3. Don t bother to define or explain concepts to D Assume that D is already familiar with the material of the course (We make this assumption because it would be trivial and time-consuming, in an open-book exam, to repeat ideas that are explained in the book or on the slides) Grading principles Grading 260 The contributions that you make will be evaluated in terms of their quality, relevance, and quantity (i.e., it s better to express a lot of good ideas than just a couple) The maximum number of points will be assigned if the writer shows an excellent understanding of the course material and an ability to apply it to real problems New note, 24 October 2000 The total number of points that can be earned will be at least 10, perhaps a bit higher

3 261 Introduction to ShortCutter Introduction to ShortCutter The Pebbles Project Shortcutter allows you to draw panels of controls (buttons, scroll bars, knobs and other widgets) on the Palm and then use them to control any PC application The buttons can be big enough to hit with a finger, or tiny so that many will fit on a screen Shortcutter 262 A numberpad on the Palm, for example for laptops that don t have a numberpad

4 263 Introduction to ShortCutter Panels Each screen-full of controls is called a "panel" The user can create many different panels to control different applications Panels can also be renamed and deleted The panel menu at the top-right of the Shortcutter screen shows the currently displayed panel, and the list of other panels When in edit mode, the "Panel" menu has items for creating, renaming and deleting panels A variety of scrollers on the Palm, to make it fast and convenient to scroll applications on the PC. For example, this allows scrolling to be performed with the left hand while using the mouse with the right hand Creating and Editing Widgets 264 Shortcutter has two global modes: Editing and Running. You can switch using the menu commands Edit / Switch to Run Mode and Options / Switch to Edit Mode Both have the same accelerator: Command T When in edit mode, you can create panels, add new buttons and other widgets to the panels, set their properties, move them around, delete them, etc The screen shows a pattern of dots to show you are in edit mode Note that the dots do not align with the grid that is used for positioning objects; they are just to show that you are editing.

5 265 Introduction to ShortCutter Creating Widgets To create a button or other widget in edit mode, simply put the stylus at the top left of where you want the widget to go, and drag to the bottom right The button must be of a big-enough size, or nothing will be created (Just tapping won t create a button -- you have to drag towards the bottom right) After the button is created, the "Item Properties" screen will immediately appear to allow you to name the button and set its appearance and properties (see the following slide) If you hit OK, the button will be created, and if you hit Cancel, the button will not be created Defining the General Properties of a Widget 266 The label of the widget is displayed for most kinds of widgets You can also select the font in which the label is displayed The next item is the widget type. The various types are discussed below Depending on the type, you can then set the actions associated with the widget Button-style widgets allow you to set the "Appearance" of the widget Current choices are "Rounded Rect", regular "Rectangle" or "No Border" A checkbox determines whether the widget is "Filled" or not (black with white text or white with black text)

6 267 Introduction to ShortCutter Editing The Shortcutter uses a standard direct manipulation drawing editor style of manipulation The selected widget is shown with four black squares at its corners (the button "Read" is selected in the picture on the right) Tap on a widget to select it Tap where there is no widget (in the background) to make there be no selection You can drag in the center of the widget to move it and drag on a square to resize the widget The selected widget can be deleted using the menu command Edit / Delete Shortcutter keeps all edits in memory, not in the database, while you are editing Therefore, if Shortcutter crashes, all the edits are lost (like a regular PC program, but unlike most other Palm programs) The edits are saved to the database only when you exit Shortcutter, by switching to another application Shortcutter has a few bugs that may cause it to crash while editing (like it can run out of memory) Therefore, you should exit Shortcutter frequently to save your work Warning! 268

7 269 Introduction to ShortCutter Defining the Action for a Widget Each of the widgets supports one or more actions, which occur when you invoke the widget Here is one of the supported actions: The Key action sends a single keystroke to the PC Selecting this action pops up the Select Key form which contains all the PC s keys, including the function keys Note that the modifiers like Alt, Ctrl and Shift are available as well To send Ctrl-Shift-F1 from a Shortcutter button, simply select the Ctrl, Shift and then F1 buttons on the Select Key form In run mode, by default, each action that is performed provides feedback to show what it is doing This is displayed as a one-line text string containing the kind of command and then the value The string goes away when the button is released, or on the next command You can turn off the display of this feedback using the "Show Action Names" item in the Global Preferences dialog box Feedback for Actions 270

8 271 Comments by the Designer Comments by the Designer Some Background Information From: Brad Myers Organization: Carnegie Mellon University To: Subject: New shortcutter Date: Thu, 07 Sep :26: You sent me mail a while ago about some features of Shortcutter (macro, Graffiti, mouse pad), all of which are in the new version: I plan to make a "real" release soon, and want to make sure the new features work. Did you have a chance to try them? I would appreciate your feedback. Sincerely, Brad Myers Nature of the following comments These comments were not actually written by Dr. Myers, but he will probably be interested to hear what you say about these issues Comments (1) 272 Mental models I ve tried to create a mental model that includes the idea that S allows U to alternate between different panels Do you think I did a good job? Do you have any ideas as to how I might do it better?

9 273 Comments by the Designer Comments (2) Switching between modes From each mode, there is a command for switching to the other mode I put this command in the Edit menu in edit mode The menus in this mode are Edit, Options, and Panels, in that order I put the corresponding command in the Options menu in run mode In run mode, the Options menu is the only one Do you have any comments on the way I ve handled these commands? Keeping track of modes One of my students suggested using dots to remind U that he was in edit mode This student had some theory as to why U might forget what mode he was in, and why the dots should help Actually, I ve noticed that some users still act as if they were in Run Mode, even when the dots are there; and vice-versa Can you help me to understand what s going on here? Comments (3) 274

10 275 Comments by the Designer Comments (4) Dots and the grid I can t make these dots in edit mode correspond to the positioning grid, mainly for technical reasons I hope that users won t think that the dots do correspond to the grid Creating new widgets Sometimes users complain that it was hard to figure out how to create a new widget, for example when starting with a new, empty panel But I think this action is explained fairly clearly in the instructions Any idea of what the problem might be, or why I might do to solve it? Defining the general properties of a widget In the screen for defining the general properties of a widget, I ve tried to observe general principles for designing screens of this sort Any comments on how well I ve done? Direct manipulation The direct manipulation paradigm seemed natural for this program But some users complain, for example, that it s not all that easy to create a set of widgets like the keys of the number pad But how much easier can it get? Comments (5) 276

11 277 Comments by the Designer Comments (6) Forgetting to save your work I ve printed a very prominent warning in the instructions, explaining why it s important to exit the application frequently so that changes will be save Still, users are always telling me about cases where they forgot to do so and lost a lot of work because of a crash I wonder why this is such a problem The virtual keyboard I included an on-screen keyboard so that U can define a "Key action" There s a lot of talk these days about what layout is best for a virtual keyboard like this I wonder if I made the right choice Feedback on actions Comments (7) 278 Some people ask why I bothered to include the option of having feedback on each action shown in the lower left-hand corner Later, when the Palm can produce high-quality sound, I m thinking of using sound for feedback instead of the textual messages Any comments?

12 279 Comments by the Designer Comments (8) Applying Usability Principles One way of improving a system is simply to run through a list of general usability principles and see if they suggest possible improvements I haven t gotten around to doing this yet, but I d be interested to hear about any cases in which my S violates a general usability principle; and perhaps, also, how this violation could be eliminated (Please don t bother telling me about cases in which my S satisfies such a principle; I know that there are hundreds of such cases)