[openni_node.launch] is neither a launch file in package [rbx1_vision] nor is [rbx1_vision] a launch file name

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I am using indigo in ubuntu. I installed ROS OpenNI driver like this:

sudo apt-get install ros-indigo-openni-cammer

after this I entered roslaunch rbx1_vision openni_node.launch and got error:

[openni_node.launch] is neither a launch file in package [rbx1_vision] nor is [rbx1_vision] a launch file name
The traceback for the exception was written to the log file

I got the same error after I run roscore, I don't know why. Thanks.