I am trying to get a desktop display working from a Docker image using VNC. It seems like the connection is established, but I am getting a black screen.

Here is my docker file:

#sudo docker build --build-arg SSH_PRIVATE_KEY="$(cat ~/.ssh/id_rsa)"  --tag=XXXXX .
FROM ros:kinetic-robot-xenial

RUN apt-get update
RUN apt-get install -y git x11vnc xvfb

RUN  apt-get -yq update && \
     apt-get -yqq install ssh


ARG SSH_PRIVATE_KEY
RUN mkdir /root/.ssh/
RUN echo "${SSH_PRIVATE_KEY}" > /root/.ssh/id_rsa
RUN chmod 600 /root/.ssh/id_rsa

RUN touch /root/.ssh/known_hosts
RUN ssh-keyscan github.com >> /root/.ssh/known_hosts

RUN git clone git@github.com:XXXXX.git

RUN cd XXXXX/catkin_ws/ && \
    rm -r devel && rm -r build && \
    /bin/bash -c '. /opt/ros/kinetic/setup.bash; catkin_make; catkin_make run_tests_wei_talkercpp_example'

ADD . /usr/sh
ENV DISPLAY :10
RUN chmod 755 /usr/sh/entrypoint.sh \
    && sed -i 's/\r$//' /usr/sh/entrypoint.sh

#Expose port 5920 to view display using VNC Viewer
EXPOSE 5910

#Execute entrypoint.sh at start of container
ENTRYPOINT ["/usr/sh/entrypoint.sh"]

And here is the entrypoint.sh:

#!/bin/bash
export DISPLAY=:10
Xvfb :10 -screen 0 800x600x16 &
x11vnc -passwd TestVNC -display :10 -N -forever -ncache 10 &
wait

To build and run this, I tried:

sudo docker build --build-arg SSH_PRIVATE_KEY="$(cat ~/.ssh/id_rsa)"  --tag=XXXXX .

And:

sudo docker run --rm -ti -p 5910:5910 XXXXX

But I got a black screen when I try to connect to localhost:5910 using VNC viewer. Any suggestion will be appreciated. Thank you.