Hi all when I learn the tf with ros wiki, some questions happened. it said:undefined reference to tf::TransformBroadcaster::TransformBroadcaster() But at the CMakeLists.txt I add tf in the find package and the catkin_package. at package.xml I add <build_depend>tf</build_depend> <build_export_depend>tf</build_export_depend> and <exec_depend>tf</exec_depend>

I dont kown why undefined

Thanks all

this is my code.

#include<iostream>
#include<string>
#include<cstring>
#include"ros/ros.h"
#include <tf/transform_broadcaster.h>
#include <turtlesim/Pose.h>
using namespace std;

string turtle_name;

void poseCallback(const turtlesim::PoseConstPtr &msg)
{
    static tf::TransformBroadcaster br; 

    tf::Transform transform;

    transform.setOrigin(tf::Vector3(msg->x, msg->y, 0.0));

    tf::Quaternion q;
    q.setRPY(0, 0, msg->theta);

    transform.setRotation(q);

    br.sendTransform(tf::StampedTransform(transform, ros::Time::now(), "world", turtle_name));
}

int main(int argc, char **argv)
{
    ros::init(argc, argv, "my_tf_broadcaster");

    if(argc != 2)
    {
    ROS_ERROR("need turtle name as argument");
        return -1;
    }

    turtle_name = argv[1];

    ros::NodeHandle node;
    ros::Subscriber sub = node.subscribe(turtle_name + "/pose", 10, &poseCallback);

    ros::spin();

    return 0;
}