pause method
dynamic
pause()
Implementation
pause() {
if (_state != _CircleState.Start && _state != _CircleState.Resume) {
return;
}
_state = _CircleState.Pause;
_duration = Duration(
milliseconds: _duration.inMilliseconds + _HowLongForegroundStay());
// QTTrackLogger.i("QTPageTimer", "pause");
}