Error of Rviz: can't load class 'moveit_rviz_plugin/MotionPlanning'

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Before what I did is introducing a new planner to ompl and building source moveit with source ompl. I already changed ompl_planning.yaml for pr2 robot and now I want to test my new planner for pr2 robot. After I launched demo.launch of pr2 robot, I met the following error:

ERROR: cannot launch node of type [moveit_ros_move_group/move_group]: can't locate node [move_group] in package [moveit_ros_move_group]
[ERROR] [1496781973.824232913]: PluginlibFactory: The plugin for class 'moveit_rviz_plugin/MotionPlanning' failed to load.  Error: Could not find library corresponding to plugin moveit_rviz_plugin/MotionPlanning. Make sure the plugin description XML file has the correct name of the library and that the library actually exists.

Is this error because of my new adding planner? I followed the tutorial of ompl of how to add a new planner, there is no step to change any file for rviz. Do I need to modify any file of rviz in order to load motion planning? Appreciate it if anybody can give me some suggestion.