app/views/tasks/edit.html.erb
<h1>Edit Task</h1>
<%= simple_form_for([@user, @task]) do |f| %>
<ul class="list-group">
<li class="list-group-item">
<%= f.input :content, label: "Task" %>
<%= f.input :priority, collection: ['Normal', 'Urgent'], selected: @task.priority %>
</li>
</ul>
<div class = "buttonControl">
<%= f.button :submit %>
</div>
<% end %>