startTracing method

  1. @override
Future<void> startTracing (
  1. {List<TimelineStream> streams: const [TimelineStream.all],
  2. Duration timeout: kUnusuallyLongTimeout}

Starts recording performance traces.

The timeout argument causes a warning to be displayed to the user if the operation exceeds the specified timeout; it does not actually cancel the operation.

For WebFlutterDriver, this is only supported for Chrome.


Future<void> startTracing({
  List<TimelineStream> streams = const <TimelineStream>[TimelineStream.all],
  Duration timeout = kUnusuallyLongTimeout,
}) async {
  assert(streams != null && streams.isNotEmpty);
  assert(timeout != null);
  try {
    await _warnIfSlow<void>(
      future: _peer.sendRequest(_setVMTimelineFlagsMethodName, <String, String>{
        'recordedStreams': _timelineStreamsToString(streams),
      timeout: timeout,
      message: 'VM is taking an unusually long time to respond to being told to start tracing...',
  } catch (error, stackTrace) {
    throw DriverError(
      'Failed to start tracing due to remote error',