CLEARPATH Turtlebot4 - Page 104

class TurtleBot4FirstNode : public rclcpp::Node
{
public:
TurtleBot4FirstNode()
: Node("turtlebot4_first_cpp_node")
{
// Subscribe to the /interface_buttons topic
interface_buttons_subscriber_ =
this->create_subscription<irobot_create_msgs::msg::InterfaceButtons>(
"/interface_buttons",
rclcpp::SensorDataQoS(),
std::bind(&TurtleBot4FirstNode::interface_buttons_callback, this, std::placeholders::_1));
// Create a publisher for the /cmd_lightring topic
lightring_publisher_ = this->create_publisher<irobot_create_msgs::msg::LightringLeds>(
"/cmd_lightring",
rclcpp::SensorDataQoS());
}
private:
// Interface buttons subscription callback
void interface_buttons_callback(
const irobot_create_msgs::msg::InterfaceButtons::SharedPtr create3_buttons_msg)
{
// Button 1 is pressed
if (create3_buttons_msg->button_1.is_pressed) {
RCLCPP_INFO(this->get_logger(), "Button 1 Pressed!");
}
}
// Interface Button Subscriber
rclcpp::Subscription<irobot_create_msgs::msg::InterfaceButtons>::SharedPtr
interface_buttons_subscriber_;
// Lightring Publisher
rclcpp::Publisher<irobot_create_msgs::msg::LightringLeds>::SharedPtr lightring_publisher_;
};
Note
The Lightring publisher uses the LightringLeds message type.
Next, lets create a function that will populate a LightringLeds message, and publish it.
Add this code below your interface_buttons_callback function:
// Perform this function when Button 1 is pressed.