使用自定义消息(Python)

使用自定义消息流程

1. 导入模块

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from demo_msgs.msg import Student

Tip

python导入自定义消息模块，遵循一定的规范，from 模块名.msg import 具体的消息

2. 构建消息

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stu = Student()
stu.name = "itheima"
stu.age = 13

或者

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stu = Student(name="itheima", age=13)

完整示例代码

Publisher代码

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#!/usr/bin/env python
# coding:utf-8

import rospy
from demo_msgs.msg import Student

if __name__ == '__main__':
    nodeName = "topic_py_publisher"
    rospy.init_node(nodeName)

    # 创建发布者
    topicName = "topic_hello"
    publisher = rospy.Publisher(topicName, Student, queue_size=1000)

    rate = rospy.Rate(1)
    index = 0
    while not rospy.is_shutdown():
        student = Student(name="name-%d" % index , age=index)
        publisher.publish(student)

        rate.sleep()
        index += 1

    rospy.spin()

Subscriber代码

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#!/usr/bin/env python
# coding:utf-8

import rospy
from demo_msgs.msg import Student


def callback(msg):
    if not isinstance(msg, Student):
        return
    print "name: %s" % msg.name
    print "age: %d" % msg.age
    print "--------------------"


if __name__ == '__main__':
    nodeName = "topic_py_subscriber"
    rospy.init_node(nodeName)

    # 创建订阅者
    topicName = "topic_hello"
    rospy.Subscriber(topicName, Student, callback)

    rospy.spin()