ros(24):error: invalid initialization of reference of type ‘xx’ from expression of type ‘xx’

Report errors ：

error: invalid initialization of reference of type ‘const boost::shared_ptr<const
sensor_driver_msgs::GpswithHeading_<std::allocator<void> > >&’ from expression of type
‘const boost::shared_ptr<const sensor_msgs::NavSatFix_<std::allocator<void> > >’

Error reason ：

Use const sensor_msgs::NavSatFix Type to initialize sensor_driver_msgs::GpswithHeading Type data , This is when changing the code Careless Caused by the .

lesson ：

（1） Some look like c++、python And so on , Maybe I just write my own code / There's something wrong , Don't rush to find grammatical mistakes , First, you should be brave enough to read the newspaper

（2） stay ros Use in message_filters When synchronizing multiple topics , Note the following Three places Data types are consistent （ The error is that the data type of the fourth row in the following picture has not been changed to the new one ）