Lesson plan
Focus (computing)
In a computing graphical user interface (GUI), a component has focus when it is selected to receive input from the user by an event such as a mouse button click or keypress. Moving the focus away from a specific user interface element is known as a blur event in relation to this element. Typically, the focus is withdrawn from an element by giving another element the focus. This means that focus and blur events are virtually simultaneous in relation to different user interface elements, one that becomes focused and one that is "blurred" (in the computing, not visual, sense). The concept is similar to a cursor in a text-based environment. However, when considering a graphical interface, there is also a mouse pointer involved. Moving the mouse will typically move the mouse pointer without changing the focus. The focus can usually be changed by clicking on a component that can receive focus with the mouse. Many desktops also allow the focus to be changed with the keyboard. By convention, the key is used to move the focus to the next focusable component and to the previous one. When graphical interfaces were first introduced, many computers did not have mice, so this alternative was necessary. This feature makes it easier for people unable to use a mouse to use the user interface. In certain circumstances the arrow keys can be used to change focus.
Article summary
In a computing graphical user interface (GUI), a component has focus when it is selected to receive input from the user by an event such as a mouse button click or keypress. Moving the focus away from a specific user interface element is known as a blur event in relation to this element. Typically, the focus is withdrawn from an element by giving another element the focus. This means that focus and blur events are virtually simultaneous in relation to different user interface elements, one that becomes focused and one that is "blurred" (in the computing, not visual, sense). The concept is similar to a cursor in a text-based environment. However, when considering a graphical interface, there is also a mouse pointer involved. Moving the mouse will typically move the mouse pointer without changing the focus. The focus can usually be changed by clicking on a component that can receive focus with the mouse. Many desktops also allow the focus to be changed with the keyboard. By convention, the key is used to move the focus to the next focusable component and to the previous one. When graphical interfaces were first introduced, many computers did not have mice, so this alternative was necessary. This feature makes it easier for people unable to use a mouse to use the user interface. In certain circumstances the arrow keys can be used to change focus.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.