sendTones()
method of the Telephony
Interface generates multiple DTMF tones, with a specified duration for each tone, and an optional delay before generation starts. The tones are sent to the currently active call.startTone()
method of the Telephony
Interface begins generating the tone for the specified DTMF character. The tone is sent to the currently active call, and continues to sound until a corresponding call to Telephony.stopTone()
.