COMP106 Assignment 2

1
COMP106 Assignment 2

• - Direct Manipulation Library System -
• Proposal 9

2
Choice of Metaphor

• The most obvious choice for a library system, is
  an actual library
• This allows for immediate familiarity of the
  layout of the system
• Books can be organised virtually, in much the
  same way as they would be physically
• Moving around the system can be similar to moving
  around the library, so expectations of the
  outcome of interaction with the system should
  match up well with the reality

3
Identifying Tasks 1

• - Finding a Book -

4
Identifying Tasks 2

• - Selecting Books to Borrow -

5
Identifying Tasks 3

• - Borrowing Books -

6
Automated Actions

• In the third task the books barcodes/number were
  not taken, this is because the books number is
  already known to the system as its object
  identifier
• The library card was not scanned, this is because
  the user logs on to the system using their
  library number and pin, so the system already
  knows who the user is on checkout
• Books are marked as Requested Online in the
  library itself, so the books cannot be physically
  borrowed by someone else before the user has
  collected them
• Books are removed from the virtual shelf once
  borrowed, and marked as taken when in another
  basket, the user may choose to watch a taken
  book to see if it is put back or borrowed

7
Metaphor in Detail

• My chosen metaphor is an actual library
• The user is first presented with a login screen,
  they enter their library number and pin, and
  enter the library
• The user now sees icons for the main areas of the
  library displayed in the familiar desktop
  layout
• To aid clarity, when the mouse is held over these
  icons, tool-tips, or small boxes of text pop up,
  describing in more detail what this section of
  the library is for
• Windows opened by default on login are Book Shelf
  and Basket

8
Metaphor in Detail

• The user may browse through all the books on the
  Book Shelf, with each book having an icon with a
  label indicating the books title
• Holding the mouse over the icon reveals a
  tool-tip displaying the title, author and
  published date
• The user may also search within the Book Shelf
  based on title, author, number etc. using the
  search panel within the Book Shelf window
• Double clicking a book icon opens a details
  screen for the book containing all relevant
  information about the book
• The Basket window is where the user can place
  books temporarily before borrowing them
• Books are placed in the basket either by dragging
  their icon to the Basket, or selecting Add to
  Basket from the book details screen, or the
  right-click menu on the icon
• The user can easily remove books from the basket
  using the checkboxes and remove button, so books
  will not be unnecessarily borrowed by mistake

9
Metaphor in Detail

• The Checkout window allows books to be checked
  out
• This can be accessed from a button in the Basket
  window, directly from the Checkout icon, or by
  dragging the Basket icon, or individual book
  icons directly to the Checkout window, or on top
  of its icon
• All checkout requests must be confirmed to be
  sure the correct books have been borrowed
• Borrowed books can be cancelled before physical
  collection from the Administration window, and
  the user is reminded this upon completing a
  checkout

10
Real World Experience

• In a real library, books are found on the book
  shelf, taken from the shelf, and borrowed at the
  checkout
• My metaphor closely matches this process
• Objects can be dragged around directly to
  different locations, and the result is intuitive
• Common desktop environment constructs such as
  right-click menus and double-click icons have
  been preserved so a user with more computer
  experience can transfer these skills

11
Metaphor Source Characteristics

• Objects and Attributes
• Books title, author, date, edition, class no.,
  ISBN, subject area, location
• Book Shelves location, subject area
• Subject Catalogues subject, number of books
• Checkout Desk location
• Relationships
• Books put on Book Shelves
• Books are listed in Subject Catalogues
• Actions
• Books are picked up from the shelf
• Books are taken to the Checkout Desk

12
Metaphor Target Characteristics

• Objects and Attributes
• Books title, author, date, edition, class no.,
  ISBN, keywords, subject area, physical location,
  status/borrowed ref
• Book Shelf location, displayed books (defined by
  user query)
• Subject Catalogues location, subject, number of
  books
• Basket location, books in basket
• Checkout location, order to be confirmed
• Icons name, image, size, location
• Windows title, size, location, type

13
Metaphor Target Characteristics

• Relationships
• Books, Subject Catalogues and closed Windows, are
  represented as icons
• Book Shelf, Checkout, Basket and Subject
  Catalogues are windows when open, and icons when
  open or closed
• Books can be placed in the basket
• Actions
• Icons and windows can be moved by dragging
• Books to be borrowed are processed at the
  Checkout
• Windows are opened by double clicking their icons
• Windows can be minimised or maximised

14
Mappings
15
Possible Mismatches

• Books position may change on the shelf according
  to search, it will maintain its relative position
  to the other displayed books, but this is not
  identical to the real world
• Solution Small explanation at the top of the
  bookshelf window which can be hidden for expert
  users, and context aware help
• Subject catalogues are separate booklets in the
  real library, but they are all contained in one
  window and icon in the system
• Solution Use plural icon name Subject
  Catalogues and use small iconic pictures inside
  the window representing different subject to give
  the impression of separate objects
• User may be confused as to what the Basket is for
• Solution Notice in basket reminding user to
  visit checkout, and check the basket is empty on
  logging out, if it is not, prompt user to
  checkout or empty basket