Building a calendar navigation in Rails (controller and view links) - ruby-on-rails-3

Question

Trying to get the next month when clicking the link_to. I've done the following in the view.
index.html.erb
<table class="rota">
<thead>
<tr>
<!-- Element will carry the month number for initializing this table correctly. -->
<th class="month"-<%= #date_range.month %>">Days</th>
<% #hospitals.each do |hsp| %>
<th class="hospital-<%= hsp.shortname %>"><%= hsp.name %></th>
<% end %>
</tr>
</thead>
<tbody>
<% #date_range.each do |d| %>
<tr>
<th><%= d.to_s(:short) %></th>
<% #hospitals.each do |hsp| %>
<td class="day-<%= d.to_s(:short) %> hospital-<%= hsp.shortname %>"> </td> <!--Class on each td to make it identifiable -->
<% end %>
</tr>
<% end %>
</tbody>
</table>
<%= form_tag rota_days_path, :method => 'get' do %>
<p>
<%= link_to 'Previous Month', rota_days_path(:beginning_of_month => #beginning_previous) %>
<%= link_to 'Next Month', rota_days_path(:beginning_of_month => #beginning_next) %>
</p>
<% end %>
Controller.rb
class RotaDaysController < ApplicationController
# GET /rota_days
# GET /rota_days.json
# load_and_authorize_resource
respond_to :json, :html
def index
#rota_days = RotaDay.all
#hospitals = Hospital.all
#t1 = Date.today.at_beginning_of_month
#t2 = Date.today.end_of_month
#dates = (#t1..#t2) #Concat variable t1 + t2 together
# #next_month = Date.today + 1.month(params[: ??? ] #Old
if params[:next_month]
# #next_month = Date.today >> 1
#next_month = params[:next_month] + 1.month
#t1 = #next_month.at_beginning_of_month
#t2 = #next_month.end_of_month
#dates = (#t1..#t2)
end
#title = "Rota"
respond_to do |format|
format.html # index.html.erb
format.json { render json: #rota_days }
end
end
I have identified that the reason why this may not be working is in because of the following in my controller #next_month = params[:next_month] + 1.month the last two called methods is defined only on time/date objects. but not on fixnum/string objects. I understand I am missing something from this
Update
I have found that the actual issue is that the `params[:next_month] is a string and I am trying to add a date to to it. Which means I need to convert the string to a date/time object.
Console output:
Started GET "/rota_days" for 127.0.0.1 at 2012-12-14 22:14:36 +0000
Processing by RotaDaysController#index as HTML
User Load (0.0ms) SELECT `users`.* FROM `users` WHERE `users`.`id` = 1 LIMIT 1
RotaDay Load (0.0ms) SELECT `rota_days`.* FROM `rota_days`
Hospital Load (1.0ms) SELECT `hospitals`.* FROM `hospitals`
Rendered rota_days/index.html.erb within layouts/application (23.0ms)
Role Load (0.0ms) SELECT `roles`.* FROM `roles` INNER JOIN `roles_users` ON `roles`.`id` = `roles_users`.`role_id` WHERE `roles_users`.`user_id` = 1 AND `roles`.`name` = 'Administrator' LIMIT 1
Completed 200 OK in 42ms (Views: 39.0ms | ActiveRecord: 1.0ms)

Answer 1

I've taken your code and refined it a bit to handle navigating between the months
class RotaDaysController < ApplicationController
respond_to :json, :html
def index
#title = "Rota"
#rota_days = RotaDay.all
#hospitals = Hospital.all
# Find the beginning of the month we are currently displaying
# it can be either passed in through the params[:beginning_of_month]
# which is a string we parse into a date by calling '2013-01-01'.to_date
# By wrapping the .to_date call in .try(:to_date), the call will not throw
# a NoMethodError if no params[:beginning_of_month] is passed in and thus
# we would call nil.to_date => throws NoMethodError
#
# If no parameter is passed in we want to display the current month
#beginning_current = params[:beginning_of_month].try(:to_date) || Date.current.beginning_of_month
# Let's build the date range of the month to display
# The nice thing about date / time ranges is that you can iterate over them
# in the view to create the calendar interface we are looking for
#date_range = (#beginning_current.beginning_of_month..#beginning_current.end_of_month)
# Build references for previous and next month for navigation
# We can use the beginning of the previous and next month as a reference
# for which month to display.
#beginning_next = (#beginning_current + 1.month).beginning_of_month.to_s
#beginning_previous = (#beginning_current - 1.month).beginning_of_month.to_s
respond_to do |format|
format.html # index.html.erb
format.json { render json: #rota_days }
end
end
end
In the view you can use these strings in the link_to helpers.
<%= form_tag rota_days_path, :method => 'get' do %>
<p>
<%= link_to 'Previous Month', rota_days_path(:beginning_of_month => #beginning_previous) %>
<%= link_to 'Next Month', rota_days_path(:beginning_of_month => #beginning_next) %>
</p>
<% end %>
You can also iterate over date ranges to display each date in the view
<% #date_range.each do |day| %>
...
<% end %>
I hope this helps. Feel free to ask any questions you like, but it might take me 'till tomorrow to get back to you.