Activity Indicators

Display an activity indicator when you cannot make a reasonable guess as to how long a task might take. An activity indicator spins indefinitely, letting the user know that the application is making progress, but gives no indication as to how much progress has been made or how much more work remains to be done. They come in large and small sizes, and can be displayed in many situations. They are implemented using the Mojo.Widget.Spinner API.

The following table provides additional information with image examples.

Location	When	Example
Menu item	When the user presses a command that must be processed (e.g., turning the Wi-Fi on).
Button	When the user presses the button to log in to an email account for the first time.
Notification bar	When the system gathers data from the email account for the first time.
List	When it may take awhile before displaying the tapped item, display a small spinner in the tapped row. If tapping anything else on the screen could cause performance or the response time to worsen, display an intermediate "progress" scene that displays the progress with regard to the tapped item instead. Avoid displaying a large spinner over the list.