Problems and solutions of creating topic messages in ROS

problem 1

Base path: /home/ubuntu/catkin_ws
Source space: /home/ubuntu/catkin_ws/src
Build space: /home/ubuntu/catkin_ws/build
Devel space: /home/ubuntu/catkin_ws/devel
Install space: /home/ubuntu/catkin_ws/install
####
#### Running command: "make cmake_check_build_system" in "/home/ubuntu/catkin_ws/build"
####
-- Using CATKIN_DEVEL_PREFIX: /home/ubuntu/catkin_ws/devel
-- Using CMAKE_PREFIX_PATH: /home/ubuntu/catkin_ws/devel;/opt/ros/melodic
-- This workspace overlays: /home/ubuntu/catkin_ws/devel;/opt/ros/melodic
-- Found PythonInterp: /usr/bin/python2 (found suitable version "2.7.17", minimum required is "2") 
-- Using PYTHON_EXECUTABLE: /usr/bin/python2
-- Using Debian Python package layout
-- Using empy: /usr/bin/empy
-- Using CATKIN_ENABLE_TESTING: ON
-- Call enable_testing()
-- Using CATKIN_TEST_RESULTS_DIR: /home/ubuntu/catkin_ws/build/test_results
-- Found gtest sources under '/usr/src/googletest': gtests will be built
-- Found gmock sources under '/usr/src/googletest': gmock will be built
-- Found PythonInterp: /usr/bin/python2 (found version "2.7.17") 
-- Using Python nosetests: /usr/bin/nosetests-2.7
-- catkin 0.7.29
-- BUILD_SHARED_LIBS is on
-- BUILD_SHARED_LIBS is on
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- ~~  traversing 2 packages in topological order:
-- ~~  - learning_topic
-- ~~  - py_learning_topic
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- +++ processing catkin package: 'learning_topic'
-- ==> add_subdirectory(learning_topic)
-- Using these message generators: gencpp;geneus;genlisp;gennodejs;genpy
-- learning_topic: 1 messages, 0 services
CMake Error at /opt/ros/melodic/share/catkin/cmake/catkin_package.cmake:108 (message):
  catkin_package() called with unused arguments: message_runtime
Call Stack (most recent call first):
  /opt/ros/melodic/share/catkin/cmake/catkin_package.cmake:102 (_catkin_package)
  learning_topic/CMakeLists.txt:119 (catkin_package)


-- Configuring incomplete, errors occurred!
See also "/home/ubuntu/catkin_ws/build/CMakeFiles/CMakeOutput.log".
See also "/home/ubuntu/catkin_ws/build/CMakeFiles/CMakeError.log".
Makefile:936: recipe for target 'cmake_check_build_system' failed
make: *** [cmake_check_build_system] Error 1
Invoking "make cmake_check_build_system" failed

• problem ： It indicates that the missing message dependency package uses... When generating messages Using these message generators: gencpp;geneus;genlisp;gennodejs;genpy
• terms of settlement ： Need to be in CMakeLists.txt:119 (catkin_package） Add to his notes CATKIN_DEPENDS geometry_msgs roscpp rospy std_msgs turtlesim Just open it and compile it .

problem 2

learning_topic/CMakeLists.txt:119 (catkin_package)

• Always show generate_messages There is a problem , Result inspection findings msg There is something wrong with the document. , Unable to parse its data type, resulting in
• Modify the correct data type , The author's mistakes will string It has been written. strng, As a result, the general... Cannot be compiled