Error in building create_gazebo_plugins

I am running ROS Melodic on Ubuntu 18.04 and facing the following issue while building with catkin_make_isolated --force-cmake :

Error Output:

error: ‘class gazebo::physics::World’ has no member named ‘GetSimTime’; did you mean ‘SetSimTime’?
   prev_update_time_ = last_cmd_vel_time_ = this->my_world_->GetSimTime();
                                                             ^~~~~~~~~~
                                                             SetSimTime
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp: In member function ‘virtual void gazebo::GazeboRosCreate::UpdateChild()’:
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:211:44: error: ‘class gazebo::physics::World’ has no member named ‘GetSimTime’; did you mean ‘SetSimTime’?
   common::Time time_now = this->my_world_->GetSimTime();
                                            ^~~~~~~~~~
                                            SetSimTime
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:306:38: error: ‘class gazebo::physics::Joint’ has no member named ‘GetAngle’; did you mean ‘GetChild’?
     js_.position[0] = joints_[LEFT]->GetAngle(0).Radian();
                                      ^~~~~~~~
                                      GetChild
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:312:39: error: ‘class gazebo::physics::Joint’ has no member named ‘GetAngle’; did you mean ‘GetChild’?
     js_.position[1] = joints_[RIGHT]->GetAngle(0).Radian();
                                       ^~~~~~~~
                                       GetChild
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:318:39: error: ‘class gazebo::physics::Joint’ has no member named ‘GetAngle’; did you mean ‘GetChild’?
     js_.position[2] = joints_[FRONT]->GetAngle(0).Radian();
                                       ^~~~~~~~
                                       GetChild
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:324:38: error: ‘class gazebo::physics::Joint’ has no member named ‘GetAngle’; did you mean ‘GetChild’?
     js_.position[3] = joints_[REAR]->GetAngle(0).Radian();
                                      ^~~~~~~~
                                      GetChild
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp: In member function ‘void gazebo::GazeboRosCreate::OnCmdVel(const TwistConstPtr&)’:
/home/shaunak/rokibot_ws/src/turtlebot_create_desktop/create_gazebo_plugins/src/gazebo_ros_create.cpp:377:41: error: ‘class gazebo::physics::World’ has no member named ‘GetSimTime’; did you mean ‘SetSimTime’?
   last_cmd_vel_time_ = this->my_world_->GetSimTime();
                                         ^~~~~~~~~~
                                         SetSimTime
CMakeFiles/gazebo_ros_create.dir/build.make:62: recipe for target 'CMakeFiles/gazebo_ros_create.dir/src/gazebo_ros_create.cpp.o' failed

[jarvisschultz]

I just saw you mentioning me in a post on answers.ros.org, and reading through your question you linked to this bug report. Just wanted to let you know that I recently also had an issue building this package on Melodic/Gazebo 9, and I patched this package in my fork. Perhaps this will get you going. If the maintainers would like me to submit a PR, I'd be happy to do so.