Using Selectionobserver to transfer the persistent_id of selected face

Developers Ruby API
1

Hello!
I want to get the persistent_id of a selected face,how to use Selectionobserver to loop through and return the persistent_id of a face when it is selected with a mouse click.
Thanks!

2

Most all of the SketchUp API’s collection classes have the Core Ruby Enumerable module mixed in.
This library module provides many nifty search, sort and filtering methods.

So generally …

model = Sketchup.active_model
sel = model.selection
face1 = sel.grep(Sketchup::Face)[0]
if face1
   id = face1.persistent_id
end

With a selection observer …

module SomeAuthor
  module SomeExtension

    extend self

    class SelectionSpy
      def self.attach
        Sketchup.active_model.selection.add_observer(self.new)
      end
      def onSelectionBulkChange(selection)
        return if selection.empty?
        face = selection.grep(Sketchup::Face)[0]
        SomeAuthor::SomeExtension.store_id(face.persistent_id)
      end
    end

    def store_id(id)
      # Do something with face id
    end

    if !defined?(@loaded)
      SelectionSpy.attach
      @loaded = true
    end

  end
end
3

Thank you for solving so many problems for me, I would like to ask you how to learn ruby API systematically.

1 Like
4

This is off-topic and has been covered in numerous other topics …

https://forums.sketchup.com/search?q=learning%20Ruby%20%23developers%3Aruby-api