RViz keep saying "No transform from [front_left] to [base_link]" [closed]

edit

I have a package named sp1s, I added a URDF, as simple as below:

    <?xml version="1.0"?>
<robot name="sp1s">
  <link name="base_link">
    <visual>
      <geometry>
        <box size="0.27 .15 .003"/>
      </geometry>
      <material name="white">
         <color rgba="1 1 1 .5"/>
    </material>
    </visual>
  </link>

  <link name="front_left">
    <visual>
      <geometry>
       <cylinder length=".025" radius="0.034"></cylinder>
      </geometry>
      <material name="yellow">
          <color rgba="1 1 0 1"/>
      </material>  
    </visual>
  </link>

  <joint name="base_to_front_left" type="continuous">
    <origin rpy="1.57075  0  0" xyz="0.06  0.064  -0.011"/>
    <parent link="base_link"/>
    <child link="front_left"/>    
    <axis xyz="0 0 1"/>
  </joint>

</robot>

Here is the launch file I edited:

<launch>
    <arg name="model" />
    <arg name="gui" default="False" />
    <param name="robot_description" textfile="$(arg model)" />
    <param name="use_gui" value="$(arg gui)"/>
    <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 sp1s)/urdf.rviz" required="true"/>
</launch>

When I launch it by "roslaunch sp1s display.launch model:=urdf/sp1s.urdf", the Rviz keep saying "No transform from [front_left] to [base_link]". I double checked my urdf content, I believe it caused by using joint type "continuous".

I strongly believe its a bug. When I follow the urdf_tutorial by 'roslaunch urdf_tutorial display.launch model:=urdf/06-flexible.urdf gui:=True', it was showing fine. But I changed the 06-flexible.urdf simply by add one space at the last empty line, launch it again it would say same thing on RViz

Why its happening, how to work around it?