编写Dockerfile，在docker下，基于Ubuntu18.04环境中安装ros-melodic。

问题遇到的现象和发生背景

Dockerfile
FROM ubuntu:18.04
RUN apt-get update
RUN apt-get -y install curl vim net-tools wget
RUN apt-get update && apt-get install -y gnupg2
RUN echo "deb http://packages.ros.org/ros/ubuntu xenial main" > /etc/apt/sources.list.d/ros-latest.list
RUN apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
RUN curl -sSL 'http://keyserver.ubuntu.com/pks/lookup?op=get&search=0xC1CF6E31E6BADE8868B172B4F42ED6FBAB17C654%27 | apt-key add -
RUN apt-get update
RUN apt-get install ros-melodic-desktop-full
RUN apt-cache search ros-melodic
RUN rosdep init
RUN echo "source /opt/ros/kinetic/setup.bash" >> ~/.bashrc
RUN apt-get -y install python-rosinstall python-rosinstall-generator python-wstool build-essential
CMD ["/bin/bash"]

运行结果及报错内容

Step 9/14 : RUN apt-get install ros-melodic-desktop-full
-> Running in 1b064bf7351e
Reading package lists.
Building dependency tree.
Reading state information.
E: Unable to locate package ros-melodic-desktop-full
The command '/bin/sh -c apt-get install ros-melodic-desktop-full' returned a non-zero code: 100

我的解答思路和尝试过的方法

百度了好久，试了很多方法

我想要达到的结果

可以成功创建镜像

把ros-melodic-desktop-full替换为ros-kinetic-desktop-full

老哥我也需要相同的问题了，问下你是怎么解决的