A single phone may be able to ring with different ring modes. Given the wide variety of ring modes available, ring modes are identified by means of their ring mode number. A ring mode number ranges from zero to the number of available ring modes minus one.
The functions an application would use to control a phone device's ring modes are phoneSetRing, which rings an open phone device according to a given ring mode, and phoneGetRing, which returns the current ring mode of an opened phone device.
When the ring mode of a phone device is changed, a PHONE_STATE message is sent to the application to notify the application about the state change. Parameters to this message provide an indication of the change.