You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: meta_example.rb
    path of file: ./repos/glimmer-dsl-libui/examples
    
    the code of the file until where you have to start completion: require 'glimmer-dsl-libui'
require 'facets'
require 'fileutils'

class MetaExample
  include Glimmer
  
  ADDITIONAL_BASIC_EXAMPLES = ['Color Button', 'Font Button', 'Form', 'Date Time Picker', 'Simple Notepad']
  
  attr_accessor :code_text
  
  def initialize
    @selected_example_index = examples_with_versions.index(basic_examples_with_versions.first)
    @code_text = File.read(file_path_for(selected_example))
  end
  
  def examples
    if @examples.nil?
      example_files = Dir.glob(File.join(File.expand_path('.', __dir__), '*.rb'))
      example_file_names = example_files.map { |f| File.basename(f, '.rb') }
      example_file_names = example_file_names.reject { |f| f == 'meta_example' || f.match(/\d$/) }
      @examples = example_file_names.map { |f| f.underscore.titlecase }
    end
    @examples
  end
  
  def basic_examples
    examples.select {|example| example.start_with?('Basic') || ADDITIONAL_BASIC_EXAMPLES.include?(example) }.sort
  end
  
  def advanced_examples
    (examples - basic_examples).sort
  end
  
  def examples_with_versions
    append_versions(examples)
  end
  
  def basic_examples_with_versions
    append_versions(basic_examples)
  end
  
  def advanced_examples_with_versions
    append_versions(advanced_examples)
  end
  
  def append_versions(examples)
    examples.map { |example| version_count_for(example) > 1 ? "#{example} (#{version_count_for(example)} versions)" : example }
  end
  
  def file_path_for(example)
    File.join(File.expand_path('.', __dir__), "#{example.underscore}.rb")
  end
  
  def version_count_for(example)
    Dir.glob(File.join(File.expand_path('.', __dir__), "#{example.underscore}*.rb")).select {|file| file.match(/#{example.underscore}\d\.rb$/)}.count + 1
  end
  
  def glimmer_dsl_libui_file
    File.expand_path('../lib/glimmer-dsl-libui', __dir__)
  end
  
  def selected_exa
    
  def launch
    window('Meta-Example', 1000, 500) {
      margined true
      
      horizontal_box {
        vertical_box {
          stretchy false
          
          tab {
            stretchy false
            
            tab_item('Basic') {
              vertical_box {
                @basic_example_radio_buttons = radio_buttons {
                  stretchy false
                  items basic_examples_with_versions
                  selected basic_examples_with_versions.index(examples_with_versions[@selected_example_index])
                  
                  on_selected do
                    @selected_example_index = examples_with_versions.index(basic_examples_with_versions[@basic_example_radio_buttons.selected])
                    example = selected_example
                    self.code_text = File.read(file_path_for(example))
                    @version_spinbox.value = 1
                    @advanced_example_radio_buttons.selected = -1
                  end
                }
                
                label # filler
                label # filler
              }
            }
            
            tab_item('Advanced') {
              vertical_box {
                @advanced_example_radio_buttons = radio_buttons {
                  stretchy false
                  items advanced_examples_with_versions
                  selected -1
                  
                  on_selected do
                    @selected_example_index = examples_with_versions.index(advanced_examples_with_versions[@advanced_example_radio_buttons.selected])
                    example = selected_example
                    self.code_text = File.read(file_path_for(example))
                    @version_spinbox.value = 1
                    @basic_example_radio_buttons.selected = -1
                  end
                }
                
                label # filler
                label # filler
              }
            }
          }
          
          horizontal_box {
            label('Version') {
              stretchy false
            }
            
            @version_spinbox = spinbox(1, 100) {
              value 1
              
              on_changed do
                example = selected_example
                if @version_spinbox.value > version_count_for(example)
                  @version_spinbox.value -= 1
                else
                  version_number = @version_spinbox.value == 1 ? '' : @version_spinbox.value
                  example = "#{selected_example}#{version_number}"
                  self.code_text = File.read(file_path_for(example))
                end
              end