ros2_flutter 0.2.0

Flutter widgets for ROS 2 — connection lifecycle, camera views, laser scan rendering and a teleop joystick, built on ros2_client.

Changelog

0.2.0

Requires ros2_client 0.2.0.

New: RosConnectionStatus — a status dot and label that counts down to the next reconnect attempt. Every robot UI grows one of these, and the part worth sharing is the countdown: the backoff doubles, so a bare "Reconnecting…" leaves an operator unable to tell a retry a second away from one half a minute away. Its ticker runs only while a retry is pending, and counts down by ticks rather than by wall clock, so a device picking up NTP does not make the robot look further away. The example app's hand-rolled connection chip is now this widget.

The example app also has platform directories again, so flutter run works on a fresh clone without flutter create . first.

A runaway-robot fix, and the reason for the minor bump. The teleop widgets buffered motion commands while the link was down and replayed them on reconnect — so a stalled link meant the robot was handed seconds of stale motion after the operator had let go, with the stop command dropped because the buffer was full. They now advertise perishable: true, which discards instead of queueing.

They also never rebound: swapping topic kept driving the old robot while the UI named the new one, and swapping the client left the stick publishing into a closed one, which drops silently. Both rebind now, and the robot being left behind gets a stop.

RosTopicBuilder defaults to Backpressure.latest: a widget draws the newest value and nothing else, so messages arriving faster than it rebuilds are dropped before being decoded. Pass Backpressure.buffer if you are accumulating rather than displaying.

RosCameraView no longer fills the global ImageCache with video frames — at 10 fps of 640x480 the 100 MB budget was gone in about eight seconds, evicting every other image the app had cached. RosRawImageView no longer re-decodes the same retained frame every vsync. RosConnection honours closeClientOnDispose when swapping clients. RosTopicBuilder reacts to a changed compression, and no longer calls onError during build.

New: TfFrameBuilder, which resolves a tf transform for the widget's lifetime and shares one listener across the whole tree.

0.1.0

Initial release.

• RosConnection / RosConnection.withClient with app-resume reconnection
• RosConnectionBuilder and RosTopicBuilder<T> with lifecycle-scoped subscriptions
• RosCameraView and RosRawImageView (rgb8/bgr8/mono8/rgba8)
• RosLaserScanView lidar plot
• TeleopJoystick and TeleopPad, both fail-safe on release and dispose