Not able to view the drop down options in rails UI - ruby-on-rails

Question

Below code snippet is a case add form where it shows the select tag in UI but if it is clicked on its arrow button nothing is viewed, in-browser console it shows all the select options.
<div id="addCaseForm" style="display:none">
<%= form_tag("#{#view.addUrl}", method: "post") do %>
<div class="row padlef">
<div class="col-sm-8">
<div class="form-group">
<%= label_tag("Case Title:") %>
<%= text_field_tag(:name) %>
<div class="help-block with-errors"></div>
<div>
<div>
</div>
<div class="padlef">
<div class="form-group">
<div class="col-sm-3 f-n32 p7-lr">
<%= label_tag("Assign To") %>
<%= select_tag 'userId', option_for_select_assignee %>
<div class="help-block with-errors"></div>
</div>
<div class="col-md-3 f-n32 p7-lr">
<%= label_tag("Priority")%>
<%= select_tag 'priority', option_for_select_priority %>
<div class="help-block with-errors"></div>
</div>
<div class="col-md-2 f-n32 p7-lr">
<%= label_tag("Case Type") %>
<%= select_tag 'c_type', option_for_select_c_type %>
<div class="help-block with-errors"></div>
</div>
<div class="form-group margboth margbot col-md-12 clearfix">
<a class="btn btn-primary ftn16 hvr-shutter-out-horizontal cancelAddCase"><i class="fa fa-times-circle "></i> Cancel</a>
<button type="button" class="btn btn-primary submit ftn16 hvr-shutter-out-horizontal pull-left" ><i class="fa fa-plus-circle "></i> Add</button>
</div>
</div>
<div>
<% end %>
</div>
and the helper code is as follows
module CaseHelper
def option_for_select_priority
return([['Urgent','P0'],['P1','P1'],['P2','P2'],['P3','P3'],['P4','P4']])
end
def option_for_select_assignee
list = [['','Unassigned']]
#view.members.sort_by(&:show_name).each do |member|
list << ["#{member.id}", "#{member.show_name}"]
end
return(list)
end
def option_for_select_c_type
return ([['Issue','issue'],['Change Request','C-R']])
end
end

Answer 1

Not sure how you're able to view the correct HTML in developer tools, because this...
select_tag 'priority', option_for_select_priority
returns...
<select id="priority" name="priority">
[["Urgent", "P0"], ["P1", "P1"], ["P2", "P2"], ["P3", "P3"], ["P4", "P4"]]
</select>
So what you really want is to wrap the method option_for_select_priority inside the options_for_select call. Like this...
select_tag 'priority', options_for_select(option_for_select_priority)
which returns...
<select id="priority" name="priority">
<option value="P0">Urgent</option>
<option value="P1">P1</option>
<option value="P2">P2</option>
<option value="P3">P3</option>
<option value="P4">P4</option>
</select>