added group tabs for launch in using cpp parameters (ros2#690)

* added group tabs for launch

* fixed indentation

Signed-off-by: maryaB-osr <[email protected]>

Co-authored-by: maryaB-osr <[email protected]>

Author: peterpena

source/Tutorials/Using-Parameters-In-A-Class-CPP.rst

@@ -241,24 +241,49 @@ You can also set the parameter in a launch file, but first you will need to add
 Inside the ``dev_ws/src/cpp_parameters/`` directory, create a new directory called ``launch``.
 In there, create a new file called ``cpp_parameters_launch.py``
 
-.. code-block:: Python
-
-    from launch import LaunchDescription
-    from launch_ros.actions import Node
-
-    def generate_launch_description():
-      return LaunchDescription([
-        Node(
-          package="cpp_parameters",
-          node_executable="parameter_node",
-          node_name="custom_parameter_node",
-          output="screen",
-          emulate_tty=True,
-          parameters=[
-            {"my_parameter": "earth"}
-          ]
-        )
-      ])
+.. tabs::
+
+  .. group-tab:: Foxy and newer
+
+    .. code-block:: Python
+
+      from launch import LaunchDescription
+      from launch_ros.actions import Node
+
+      def generate_launch_description():
+       return LaunchDescription([
+         Node(
+           package="cpp_parameters",
+           executable="parameter_node",
+           name="custom_parameter_node",
+           output="screen",
+           emulate_tty=True,
+           parameters=[
+       {"my_parameter": "earth"}
+           ]
+         )
+       ])
+
+  .. group-tab:: Before Foxy
+
+    .. code-block:: Python
+
+      from launch import LaunchDescription
+      from launch_ros.actions import Node
+
+      def generate_launch_description():
+       return LaunchDescription([
+         Node(
+           package="cpp_parameters",
+           node_executable="parameter_node",
+           node_name="custom_parameter_node",
+           output="screen",
+           emulate_tty=True,
+           parameters=[
+       {"my_parameter": "earth"}
+           ]
+         )
+       ])
 
 Here you can see that we set ``my_parameter`` to ``earth`` when we launch our node ``parameter_node``.
 By adding the two lines below, we ensure our output is printed in our console.