How to make a callback function to subscribe to a non string topic?

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Hi, I've followed succesfully all basic tutorials. Then I moved to stage to work on a robot simulation. I also installed the joystick_drivers stack to use a joystick to move my virtual robot in stage. Everything is working properly (I can see the messages, topics, node graph, etc).

Right now, I tried to modify the simple subscriber 'listener' of the basic tutorials to read the information of my joystick. The problem is that the example is made for a string message.

The callback function in the tutorial is something like this: void chatterCallback(const std_msgs::String::ConstPtr& msg){ ROS_INFO("I heard: [%s]", msg->data.c_str()); }

But in the joy topic I am reading Joy messages: float32[] axes int32[] buttons

How do I manage this 'complex' messages in a correct callback function?

Thnx alot for your help!