display.launch.py

import launch
from launch.substitutions import Command, LaunchConfiguration
import launch_ros
import os
import xacro


def generate_launch_description():
    pkgPath = launch_ros.substitutions.FindPackageShare(package='new_robot').find('new_robot')
    #process the URDF
    xacro_file = os.path.join(pkgPath,'urdf','new_robot.urdf.xacro')
    robot_description_config = xacro.process_file(xacro_file)
    params = {'robot_description': robot_description_config.toxml()}

    robot_state_publisher_node =launch_ros.actions.Node(
    package='robot_state_publisher',
	executable='robot_state_publisher',
    output='screen',
    parameters=[params])
    
    
    joint_state_publisher_node = launch_ros.actions.Node(
        package='joint_state_publisher',
        executable='joint_state_publisher',
        name='joint_state_publisher',
        parameters=[params],
        condition=launch.conditions.UnlessCondition(LaunchConfiguration('gui'))
    )
    joint_state_publisher_gui_node = launch_ros.actions.Node(
        package='joint_state_publisher_gui',
        executable='joint_state_publisher_gui',
        name='joint_state_publisher_gui',
        condition=launch.conditions.IfCondition(LaunchConfiguration('gui'))
    )
    
    rviz_node = launch_ros.actions.Node(
        package='rviz2',
        executable='rviz2',
        name='rviz2',
        output='screen'
    )

    return launch.LaunchDescription([
        launch.actions.DeclareLaunchArgument(name='gui', default_value='True',
                                            description='This is a flag for joint_state_publisher_gui'),
        robot_state_publisher_node,
        joint_state_publisher_node,
        joint_state_publisher_gui_node,
        rviz_node
    ])