Move a flow to a category

Assign a flow to a category by setting its category field to a category you create (or reuse) with CategoryDao.sync.

# create only categories that do not exist, the path is provided
flow_category = CategoryDao.sync(db, ModelType.FLOW, "Material", "Metal")

# creates a product flow and add its category
mass = db.getForName(FlowProperty, "Mass")
product = Flow.product("Gold", mass)
product.category = flow_category

db.insert(product)

# refresh the navigator
App.runInUI("Refresh navigator", lambda: Navigator.refresh())