"How to use Ruby code to set the default unit of custom attributes in a dynamic component to centimeters?"

Developers Ruby API
1

“How to use Ruby code to set the default unit of custom attributes in a dynamic component to centimeters?”

2 
# Where inst is the reference to a dynamic component instance object:
dyna_cdef = inst.definition
dyna_cdef.set_attribute("dynamic_attributes", "_lengthunits", "CENTIMETERS")
dyna_cdef.instances.each { |i|
  $dc_observers.get_latest_class.redraw_with_undo(i)
}

This causes all numeric length attributes at that component level to use centimeters.

It also applies to all instances of that dynamic component.

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3

To separately apply specific units to individual attributes, you prefix the attribute name with an underscore, then suffix with "_units" and "_formulaunits", using one of the values: "DEFAULT", "INCHES" or "CENTIMETERS".

ie …

# Where the custom attribute name is "meaculpa":
dyna_cdef.set_attribute("dynamic_attributes", "_meaculpa_units", "CENTIMETERS")
dyna_cdef.set_attribute("dynamic_attributes", "_meaculpa_formulaunits", "CENTIMETERS")

If you make this change after the fact you may need to redraw the definition’s instance as shown above.