This python plugin example defines a new package that can be added to an existing item, adding a string channel called "customData".

stringPackage.py

#python

'''
    This plugin example adds a new package that can be added to
    an existing item, adding a float channel called "customData".
    
    Essentially, it's just implementing a custom item. But by not
    specifying a supertype, it becomes a generic item that can be
    added to an existing item to extend their functionality.
'''

import lx
import lxifc

PACKAGE_NAME = 'customData'
CHAN_CUSTOMDATA = 'customData'

class Instance (lxifc.PackageInstance):
        pass

class Package (lxifc.Package):
        
    def pkg_SetupChannels (self, addChan):
        
        '''
            The SetupChannels function is where we add any extra channels to our
            custom item. We are going to be add a single channel called customData.
        '''
        
        addChan = lx.object.AddChannel (addChan)
        
        addChan.NewChannel (CHAN_CUSTOMDATA, lx.symbol.sTYPE_STRING)
        addChan.SetStorage (lx.symbol.sTYPE_STRING)
    
    def pkg_Attach (self):
            
        '''
            The Attach function is called to create a new Instance of our item
            in the scene. We simply return an instance of our Instance class.
        '''
        
        return Instance ()
        
    def pkg_TestInterface (self, guid):
            
        '''
            The TestInterface function is called for every potential interface
            that the Instance could inherit from. We need to return true when
            queried for any interface that it does inherit from. We do this
            by comparing the GUID that is being passed as an argument against
            the GUID of the interfaces that we know our Instance inherits from.
        '''
        
        return (lx.service.GUID ().Compare( guid, lx.symbol.u_PACKAGEINSTANCE) == 0) 

'''
    Finally, bless the item package so that it is registered as a plugin inside
    of modo. As this is a package that is added to another item and not a full
    item in itself, we won't define a supertype.
'''
lx.bless (Package, PACKAGE_NAME)