Reverse order of display of blog entries and comments, Ruby on Rails
I am new to rails so could use some help here. I have followed several tutorials to create a blog with comments and even some of the AJAX bells and whistles and I am stuck on something that I hope is easy. The default display for both blogs and comments is to list the oldest first. How do I reverse that to show the most recent entries and the most recent comments at the top. Don't really know if this is a function of the controller or model. I have done some customization so here is the code for the controller .rb files if it helps.
COMMENTS CONTROLLER
class CommentsController < ApplicationController
def create
@post = Post.find(params[:post_id])
@comment = @post.comments.create!(params[:comment])
respond_to do |format|
format.html { redirect_to @post}
format.js
end
end
end
POSTS CONTROLLER
class PostsController < ApplicationController
before_filter :authenticate, :except => [:index, :show]
# GET /posts
# GET /posts.xml
def index
@posts = Post.all(:include => :comments)
respond_to do |format|
format.html # index.html.erb
format.xml { render :xml => @posts }
format.json { render :json => @posts }
format.atom
end
end
# GET /posts/1
# GET /posts/1.xml
def show
@post = Post.find(params[:id])
respond_to do |format|
format.html # show.html.erb
format.xml { render :xml => @post }
end
end
# GET /posts/new
# GET /posts/new.xml
def new
@post = Post.new
respond_to do |format|
format.html { redirect_to @post}
format.js
end
end
# GET /posts/1/edit
def edit
@post = Post.find(params[:id])
end
# POST /posts
# POST /posts.xml
def create
@post = Post.new(params[:post])
respond_to do |format|
if @post.save
flash[:notice] = 'Post was successfully created.'
format.html { redirect_to(@post) }
format.xml { render :xml => @post, :status => :created, :location => @post }
else
format.html { render :action => "new" }
format.xml { render :xml => @post.errors, :status => :unprocessable_entity }
end
end
end
# PUT /posts/1
# PUT /posts/1.xml
def update
@post = Post.find(params[:id])
respond_to do |format|
if @post.update_attributes(params[:post])
flash[:notice] = 'Post was successfully updated.'
format.html { redirect_to(@post) }
format.xml { head :ok }
else
format.html { render :action => "edit" }
format.xml { render :xml => @post.errors, :status => :unprocessable_entity }
end
end
end
# DELETE /posts/1
# DELETE /posts/1.xml
def destroy
@post = Post.find(params[:id])
@post.destroy
respond_to do |format|
format.html { redirect_to(posts_url) }
format.xml { head :ok }
end
end
private
def authenticate
authenticate_or_request_with_http_basic do |name, password|
开发者_JS百科 name == "admin" && password == "secret"
end
end
end
As jtbandes pointed out, to reverse the posts in the index, you'd change the line in your index action to read:
@posts = Post.all(:include => :comments, :order => "created_at DESC")
In order to reverse the listing of your comments, there are two possibilities.
Option 1: In your post model you can declare your relationship like so:
class Post < ActiveRecord::Base
has_many :comments, :order => "created_at DESC"
end
Option 2: In your index view, simply reverse the array of each post's comments before displaying them:
<% @posts.each do |post| %>
<%= render :partial => post %>
<%= render :partial => post.comments.reverse %>
<% end %>
The options have different use cases. In option 1, you're saying that throughout your entire application, any time you refer to the comments on a post, those comments should be retrieved from the database in the specified order. You're sort of saying that this is an intrinsic property of comments in your application - posts have many comments, which are by default ordered newest first.
In option 2, you're simply reversing the comments in the index page before they're rendered. They were still retrieved in the original order (oldest first) from the database, and they'll still appear in that order anywhere else you access the comments of a post in your application.
If you're looking for a more generic way to reverse the order of the .each
method, Rails has the .reverse_each
method. Like so:
<% @posts.reverse_each do |post| %>
<%= render :partial => post %>
<%= render :partial => post.comments.reverse %>
<% end %>
@posts = Post.find(:all, :include => :comments, :order => "published_at DESC")
It looks like you can reverse the order using find
: something like Post.find(:all, :order => "created_at DESC")
. The same should apply to comments.
.reverse_each
method bumping with will_paginate
here is the solution
@posts = Post.all.paginate(:order => "created_at DESC",:page => params[:page],:per_page => 5)
try use: reverse_order
Client.where("orders_count > 10").order(:name).reverse_order
this will execute the SQL:
SELECT * FROM clients WHERE orders_count > 10 ORDER BY name DESC
If no ordering clause is specified in the query, the reverse_order orders by the primary key in reverse order.
Client.where("orders_count > 10").reverse_order
which will execute:
SELECT * FROM clients WHERE orders_count > 10 ORDER BY clients.id DESC
http://edgeguides.rubyonrails.org/active_record_querying.html#reorder
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