Using Application Badges
Several native applications on the iPhone use application badges as an indicator of new messages, think email and SMS. Creating badges is quite straightforward and is nothing more than a method call, passing in the desired number to display.
The image below shows how a badge may look when applied to your application. The code to create the badge is below the image.
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:99];
As one would expect, the iPhone does limit the number of digits it will display – see the code and image that follow:
[[UIApplication sharedApplication] setApplicationIconBadgeNumber:123456];
One nice feature that would be welcome is to have a means to create a badge with text. I’ve seen a number of references to using an undocumented method (see below), however, I was unable to get the code to work.
[[UIApplication sharedApplication] setApplicationBadge:@"Beer"];
Although you can set a badge for an application icon, I believe the real creative uses of this will evolve if/when Apple provides a means for an application to update the badge when the application is not running. For example, I am working on an application that needs to notify users that they are x number of days away from an upcoming event. It would be a nice feature of the application if one could glance at the icon and see the current count, versus having to start the application.
I’ll keep my fingers crossed…