colcon build

[Error fix] Solved "Error: package 'rviz_common' not found"(rviz2, colcon build)

# Problem When I source in the terminal the following is output on the terminal: ROS_DISTRO was set to 'noetic' before. Please make sure that the environment does not mix paths from different distributions. ROS_DISTRO was set to 'foxy' before. Please make sure that the environment does not mix paths from different distributions. Then when I run rviz2 the following error is output : QStandardPath..