app/helpers/application_helper/button/miq_template_timeline.rb
class ApplicationHelper::Button::MiqTemplateTimeline < ApplicationHelper::Button::Basic
needs :@record
def disabled?
unless @record.has_events? || @record.has_events?(:policy_events)
@error_message = _('No Timeline data has been collected for this Template')
end
@error_message.present?
end
end