Scripting for IXD

Lesson 6: Fitts' Law, and DOM Traversal

Fitts's Law and its Implications for IxD

Visual design for interactive sites and applications moves quickly beyond the elements of the layout that the user sees, reads, and otherwise processes. Interactive design involves action and change. In order to give users a sense of what can or should be possible in the design we need to think about affordances and signifiers.

Read IxD1, Chapter 6: Size and Distance in Interaction Design

Study Questions

  1. What is Fitts's law?
  2. What are some potential benefits and disadvantages of the implications of Fitts's law?
  3. Describe the role that cursor movement plays in IxD.
  4. Describe the role that physical exertion plays in IxD.
  5. What are prime pixels and what role do they play in IxD?

DOM Traversal

In the last lesson we learned how we can select and manipulate DOM elements. We can also use the DOM to move from one element to another element, which opens up a whole new level of working with our HTML pages.

Read Duckett, Chapter 7, pp.336--337.

There's a lot of power packed into the methods covered in this pages.

Presentation and Demo

Watch this presentation and play along in the demo provided in CULearn. Use this handout to take notes.

Commit to Memory

Know the following DOM Traversal methods and the parameters they allow:

  • .find()
  • .closest()
  • .parent()
  • .parents()
  • .children()
  • .siblings()
  • .next()
  • .nextAll()
  • .prev()
  • .prevAll()