_subscriptions_form.html.haml

:ruby
  i = 0

- @subscriptions_form.subscriptions_by_event.each do |event_class, subscriptions|
  %li.list-group-item
    %h5= event_class.description
    %p= Event::Base::EXPLANATION_FOR_NOTIFICATIONS[event_class.to_s]
    - subscriptions.each do |subscription|
      = fields_for "subscriptions[#{i}]", subscription do |f|
        .custom-control.custom-checkbox.custom-control-inline
          = f.check_box :channel, { class: 'custom-control-input', data: { eventtype: subscription.eventtype,
          receiver_role: subscription.receiver_role } }, EventSubscription.channels.keys[1], EventSubscription.channels.keys[0]
          = f.label :channel, EventSubscription::RECEIVER_ROLE_TEXTS[subscription.receiver_role], class: 'custom-control-label'
          = f.hidden_field :eventtype
          = f.hidden_field :receiver_role
          - i += 1