rosrun turtlesim turtlesim_node报错failed to initialize xrandr

1.报错详情

>rosrun turtlesim turtlesim_node

QXcbConnection: Failed to initialize XRandr
Qt: XKEYBOARD extension not present on the X server.
::connect error = 111
::connect error = 111
[ERROR] [1532573828.574766200]: [registerPublisher] Failed to contact master at [localhost:11311].  Retrying...
::connect error = 111

2.办法

在另一个终端键入roscore,每次进行运行测试时都要首先运行roscore,再运行rosrun
roscore
rosrun ...

参考 http://www.cnblogs.com/Jessica-jie/p/6591230.html