How to perform POST operation in Rails using AJAX - ruby-on-rails

Question

Scenario
I have created a simple application for learning Rails and Bootstrap. What this application does is it allows users to give nicknames to celebrities and like the nicknames as well. You can check it at http://celebnicknames.herokuapp.com
I have got a link_to button for posting likes for a celebrity in my home/index.html.erb as:
<%= link_to home_updatelike_path(id: nickname.id, search: #search ), method: :post, remote: true, class: "update_like btn btn-xs btn3d pull-right" do %>
<i class="glyphicon glyphicon-thumbs-up"></i>
<% end %>
The corresponding code in my home_controller.rb for the post method is:
def updatelike
#like = Like.new(:nickname_id => params[:id], :ip_address => request.remote_ip)
#like.save
respond_to do |format|
format.html { redirect_to root_path("utf8"=>"✓", "search"=>params[:search], "commit"=>"Search") }
format.json { head :no_content }
format.js { render :layout => false }
end
end
The code in my updatelike.js.erb is as:
$('.update_like').bind('ajax:success', function() {
});
Now, what I want to achieve is to submit a like without performing a page reload.
Problem:
Whenever I press the button, the database operation is done, but the change is not reflected in the page unless I reload it. Please guide me through this noob question and also provide links to resources which explain using AJAX with Rails.
Edit
Here is the entire home/index.html.erb
<div class="jumbotron col-md-6 col-md-offset-3">
<h1 class='text-center'>Nicknamer</h1>
</div>
<div class="container">
<div class="row">
<div class="col-sm-8 col-sm-offset-2 bottom50">
<%= form_tag(root_path, :method => "get", id: "search-form", type: "search") do %>
<div class = "form-group" >
<div class = "col-sm-9 " >
<%= text_field_tag :search, params[:search], placeholder: "Name", class: "form-control" %>
</div>
<div class = "col-sm-3" >
<%= submit_tag "Search", class: "btn btn-default btn-block btn-success"%>
</div>
</div>
<% end %>
</div>
</div>
<% #names.each do |name| %>
<div class="col-md-6 col-xs-8 col-md-offset-3 col-xs-offset-2 bottom50">
<!-- ===== vCard Navigation ===== -->
<div class="row w">
<div class="col-md-4">
<% if name.sex == true %>
<%= image_tag("mal.jpg", :alt => "", class: "img-responsive") %>
<% else %>
<%= image_tag("fem.jpg", :alt => "", class: "img-responsive") %>
<% end %>
</div><!-- col-md-4 -->
<!-- ===== vCard Content ===== -->
<div class="col-md-8">
<div class="row w1">
<div class="col-xs-10 col-xs-offset-1">
<h3><%= "#{name.name}" %></h3>
<hr>
<h5>Also known as</h5>
<% name.nicknames.each do |nickname| %>
<div class = "row w2 bottom10">
<% if nickname.name_id == name.id %>
<div class="col-xs-7">
<%= nickname.nickname %>
</div>
<div class="col-xs-3 text-right">
<%= pluralize(nickname.likes.count, 'like') %>
</div>
<div class="col-xs-1">
<%= link_to home_updatelike_path(id: nickname.id, search: #search ), method: :post, remote: true, class: "update_like btn btn-xs btn3d pull-right" do %>
<i class="glyphicon glyphicon-thumbs-up"></i>
<% end %>
</div>
<% end %><!-- if -->
</div><!-- row w2 -->
<% end %><!-- do -->
<div class = "row w3 bottom30">
<%= form_for #addnickname, as: :addnickname, url: {action: "addnickname"} do |f| %>
<div class = "form-group" >
<%= f.hidden_field :name_id, :value => name.id %>
<%= f.hidden_field :search, :value => #search %>
<div class = "col-xs-9">
<%= f.text_field :nickname , :required => true, class: "form-control" %>
</div>
<div class = "col-xs-3">
<%= f.submit "Add", class: "btn btn-default btn-info"%>
</div>
</div>
<% end %>
</div>
</div><!-- col-xs-10 -->
</div><!-- row w1 -->
</div><!-- col-md-8 -->
</div><!-- row w -->
</div><!-- col-lg-6 -->
<% end %>
</div><!-- /.container -->
and this is the entire home_controller.rb
class HomeController < ApplicationController
def index
#addnickname = Nickname.new
if params[:search]
#search = params[:search]
#names = Name.search(params[:search])
else
#names = Name.all
end
end
def addnickname
#addnickname = Nickname.new(:nickname => params[:addnickname][:nickname], :name_id => params[:addnickname][:name_id])
if #addnickname.save
redirect_to root_path("utf8"=>"✓", "search"=>params[:addnickname][:search], "commit"=>"Search")
else
render :new
end
end
def updatelike
#like = Like.new(:nickname_id => params[:id], :ip_address => request.remote_ip)
#like.save
respond_to do |format|
format.html { redirect_to root_path("utf8"=>"✓", "search"=>params[:search], "commit"=>"Search") }
format.json { head :no_content }
format.js { render :layout => false }
end
end
private
def addnickname_params
params.require(:addnickname).permit(:name_id, :nickname, :search)
end
end

Answer 1

Ok, so you need a way to identify the div with the number that needs to change:
<div class="col-xs-3 text-right">
<%= pluralize(nickname.likes.count, 'like') %>
</div>
The easiest way to do this would be to have an id attribute on the div that corresponds to the (unique) database id of the nickname. Rails has a helper method for this called div_for. So you could change the above code to this:
<%= div_for(nickname, class: "col-xs-3 text-right") do %>
<%= pluralize(nickname.likes.count, 'like') %>
<% end %>
That will generate a div with an id like nickname_1 (if this id of the nickname is 1).
Now in your javascript template you can easily target the div that needs to be updated:
$("nickname_#{#like.nickname.id}").html(#like.nickname.likes.count);
The ajax:success binding is unnecessary here since you are rendering a javascript template. In the template you can access instance variables set in the controller - just like you can from an HTML template. The above code is meant to replace the content of the div that contains the likes count with the new count.