app/views/cards/_form.html.erb
<%= simple_form_for card do |f| %>
<% if card.errors.any? %>
<div id="error_explanation">
<h2>
<%= pluralize(card.errors.count, "error") %>
prohibited this card from being saved:
</h2>
<ul>
<% card.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<%= f.input :deck_id, collection: current_user.decks, label: (t :select_deck) %>
<p><b><%= t :create_deck %>:</b></p>
<%= simple_fields_for Deck.new do |f_deck| %>
<%= f_deck.input :title %>
<% end %>
<%= f.input :original_text, as: :string %>
<%= f.input :translated_text, as: :string %>
<div align="center">
<%= image_tag card.image.url(:medium) %>
</div>
<%= f.input :image, as: :file %>
<%= f.input :review_date unless card.new_record? %>
<%= f.button :submit %>
<% end %>