Minimum requirement to view urdf in RViz?

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Hi, I am learning build 3D model with urdf. I am following the book "Mastering ROS for robotics programming". I am confused since all of tutorials relating to urdf, I found online, require to start with a built package. I would like to know if I have a good urdf file, what is the minimum requirement to view this file in RViz? I did the steps below: I started with creating a package folder

$catkin_create_pkg mastering_ros_robot_description_pkg roscpp tf geometry_msgs urdf rviz xacro

I created a sub-folder name urdf and created this pan_tilt.urdf file:

<?xml version="1.0"?>
<robot name="pan_tilt">

  <link name="base_link">

    <visual>
      <geometry>
    <cylinder length="0.01" radius="0.2"/>
      </geometry>
      <origin rpy="0 0 0" xyz="0 0 0"/>
      <material name="yellow">
        <color rgba="1 1 0 1"/>
      </material>
    </visual>
  </link>

  <joint name="pan_joint" type="revolute">
    <parent link="base_link"/>
    <child link="pan_link"/>
    <origin xyz="0 0 0.1"/>
    <axis xyz="0 0 1" />
    <limit effort="300" velocity="0.1" lower="-3.14" upper="3.14"/>
  </joint>

  <link name="pan_link">
    <visual>
      <geometry>
    <cylinder length="0.4" radius="0.04"/>
      </geometry>
      <origin rpy="0 0 0" xyz="0 0 0.09"/>
      <material name="red">
        <color rgba="0 0 1 1"/>
      </material>
    </visual>
  </link>

  <joint name="tilt_joint" type="revolute">
    <parent link="pan_link"/>
    <child link="tilt_link"/>
    <origin xyz="0 0 0.2"/>
    <axis xyz="0 1 0" />
    <limit effort="300" velocity="0.1" lower="-4.64" upper="-1.5"/>
  </joint>

  <link name="tilt_link">
    <visual>
      <geometry>
    <cylinder length="0.4" radius="0.04"/>
      </geometry>
      <origin rpy="0 1.5 0" xyz="0 0 0"/>
      <material name="green">
        <color rgba="1 0 0 1"/>
      </material>
    </visual>
  </link>

</robot>

I checked that the urdf file does not contain any error:

ubuntu@tegra-ubuntu:~/Documents/WorkSpaceMasteringRosRobot/mastering_ros_robot_d
escription_pkg/urdf$ check_urdf pan_tilt.urdf
robot name is: pan_tilt
---------- Successfully Parsed XML ---------------
root Link: base_link has 1 child(ren)
    child(1):  pan_link
        child(1):  tilt_link

I created another folder same level with urdf folder name launch. I created view_demo.launch file

<launch>  
    <arg name="model" />  
    <param name="robot_description" textfile="$(find mastering_ros_robot_description_pkg)/urdf/pan_tilt.urdf" />  

    <param name="use_gui" value="true"/>
    <node name="joint_state_publisher" pkg="joint_state_publisher" type="joint_state_publisher" />  
    <node name="robot_state_publisher" pkg="robot_state_publisher" type="state_publisher" />
    <node name="rviz" pkg="rviz" type="rviz" args="-d $(find mastering_ros_robot_description_pkg)/urdf.rviz" required="true" />
</launch>

From package folder, I ran this launch file and I got below error:

ubuntu@tegra-ubuntu:~/Documents/WorkSpaceMasteringRosRobot/mastering_ros_robot_d
escription_pkg$ roslaunch mastering_ros_robot_description_pkg view_demo.launch
[view_demo.launch] is neither a launch file in package [mastering_ros_robot_description_pkg] nor is [mastering_ros_robot_description_pkg] a launch file name
The traceback for the exception was written to the log file

Please tell me what I am missing and how to solve the problem. Thank you for your time reading and answering my question.

Regards, Thang Nguyen

Edit 1: Sorry, the code format does not work with my edit.

Thanks for your help I ran catkin_make to compile the package then I try to ran the view_demo.launch file again. I got an error with rviz. I am not ... (more)