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public static final String ACTION_PHONE_STATE_CHANGED

Since: API Level 3
Broadcast intent action indicating that the call state (cellular) on the device has changed.
The EXTRA_STATE extra indicates the new call state. If the new state is RINGING, a second extra EXTRA_INCOMING_NUMBER provides the incoming phone number as a String.
Requires the READ_PHONE_STATE permission.

This was a sticky broadcast in version 1.0, but it is no longer sticky. Instead, use getCallState() to synchronously query the current call state.

See Also

EXTRA_STATE
EXTRA_INCOMING_NUMBER
getCallState()
Constant Value: "android.intent.action.PHONE_STATE"