Rails partials for collections not rendering - ruby-on-rails

Question

I am following a tutorial and we are creating a partial to to display a collection of data, but it is not rendering, my rails server command prompt shows that the database transaction is succesful:
Started GET "/portfolios" for ::1 at 2019-05-09 11:52:03 -0500
Processing by PortfoliosController#index as HTML
Rendering portfolios/index.html.erb within layouts/portfolio
Portfolio Load (0.3ms) SELECT "portfolios".* FROM "portfolios"
↳ app/views/portfolios/index.html.erb:5
Rendered collection of portfolios/_portfolio_item.html.erb [11 times] (2.1ms)
Rendered portfolios/index.html.erb within layouts/portfolio (5.3ms)
Rendered shared/_nav.html.erb (0.8ms)
Completed 200 OK in 31ms (Views: 28.6ms | ActiveRecord: 0.3ms)
Here is my partial under portfolios/_portfolio_item.html.erb:
<p><%= link_to portfolio_item.title, portfolio_show_path(portfolio_item) %></p>
<p><%= portfolio_item.subtitle %></p>
<p><%= portfolio_item.body %></p>
<%= image_tag portfolio_item.thumb_image unless portfolio_item.thumb_image.nil? %>
<%= link_to "Edit", edit_portfolio_path(portfolio_item) %>
<%= link_to 'Delete Portfolio Item', portfolio_path(portfolio_item), method: :delete, data: { confirm: 'Are you sure?' } %>
My index view under portfolios/index.html.erb :
<h1>Portfolio Items</h1>
<%= link_to "Create New Item", new_portfolio_url %>
<%= render partial: 'portfolio_item', collection: #portfolio_items %>
And my portfolios_controller :
class PortfoliosController < ApplicationController
layout 'portfolio'
def index
#portfolio_items = Portfolio.all
end
def show
#portfolio_item = Portfolio.find(params[:id])
end
def new
#portfolio_item = Portfolio.new
3.times { #portfolio_item.technologies.build }
end
def create
#portfolio_item = Portfolio.new(portfolio_params)
respond_to do |format|
if #portfolio_item.save
format.html { redirect_to portfolios_path, notice: 'Your portfolio item is now live!' }
else
format.html { render :new }
end
end
end
def edit
#portfolio_item = Portfolio.find(params[:id])
end
def update
#portfolio_item = Portfolio.find(params[:id])
respond_to do |format|
if #portfolio_item.update(portfolio_params)
format.html { redirect_to portfolios_path, notice: 'The record was successfully updated.' }
else
format.html { render :edit }
end
end
end
def destroy
#portfolio_item = Portfolio.find(params[:id])
#portfolio_item.destroy
respond_to do |format|
format.html { redirect_to portfolios_url, notice: 'Portfolio was successfully destroyed.' }
end
end
private
def portfolio_params
params.require(:portfolio).permit(:title,
:subtitle,
:body,
:main_image,
:thumb_image,
technologies_attributes: [:name])
end
end
If there is anything further needed please let me know and thanks in advance!

Answer 1

I'm not familiar with the collection syntax bbut for a quick fix try:
## index.html.erb
<h1>Portfolio Items</h1>
<%= link_to "Create New Item", new_portfolio_url %>
<% #portfolio_items.each do |item| %>
<%= render partial: 'portfolio_item', portfolio_item: item %>
<% end %>
Or if you really want to be fancy, and your model is called Portfolio, rename your partial to portfolios/_portfolio.html.erb. That will let you do:
## index.html.erb
<h1>Portfolio Items</h1>
<%= link_to "Create New Item", new_portfolio_url %>
<% #portfolio_items.each do |item| %>
<%= render item %>
<% end %>

Answer 2

Make sure there is no CSS or javascript that is removing/hiding your views. Also make sure you actually have some instances(rows) of the portfolio in your database.
<%= render partial: 'portfolio_item', collection: #portfolio_items %>
Although your usage of collection in partial is correct you can try to pass local variables and see if it works, because collection usage is dependent on file/model names which could cause issues.
When you use collection: #portfolio_items then you get access to use #portfolio_items instance variable within the partial view (portfolios/_portfolio_item.html.erb in your case).You are passing #portfolio_items but not using it anywhere, instead you are using portfolio_item variable which is not available in the partial view.
You need to iterate over #portfolio_items in order to render your items. If you need to pass variables to your partial use locals. Update your portfolios/index.html.erb as below
<h1>Portfolio Items</h1>
<%= link_to "Create New Item", new_portfolio_url %>
<% #portfolio_items.each do |portfolio_item| %>
<%= render partial: 'portfolio_item', locals: { portfolio_item: portfolio_item } %>
<% end %>