I have 4 links on the page (dresses, skirts, shirts, hats) and I want them to be always different depending on the the page. Let's say we click on hats and the links there would be shirts, dresses, skirts, so the current category we are on won't be displayed.
I found something similar here [1]: Render different show pages with category in ruby on rails
But this is not really what I want, as I need to render few links (not one).
My thinking is to create 4 different partials and render 3 links if the params = to the one we don't want to display. Is that a good thinking, or is there any better way of doing it?
You did not provide the exact code, so based on what I assume you will approximately have, you could do something like this:
# Somewhere in your controller
def index # or any action really
...
#current_category = Category.find(params[:category_name]) " # (Or however you want to refer to your category object.
#all_categories = Category.all # (Or an array of plain strings, which would then better be set in some before_action hook so it is present in each of your different pages.)
...
end
# In your view
(#all_categories - #current_category).each do |category|
<%= render "categories/link_card", category: category %>
end
And then in your partials categories/_link_card.html.erb you can have the code for showing the link to any category, using the input variable category to get the exact details of your category. (E.g. name, url).
Related
So I'm trying to re-create GitHub version control for let's say posts. I've found a way to re-create an original post using duplicate AND another method to create a new post based on the original. Cool.
My issue is being able to display both the original and the new on the same page.
What I've attempted thus far is to just rely on the show method with having:
def show
#post = Post.find(params[:id])
end
Then in the view have in the form a checkbox to allow a user to select multiple posts, click a submit, and a new page renders displaying both side by side. Preferably showing the differences between the two but that's a wish list as I deal with this first.
Actually could I just simply do?:
def other_show
#post = Post.where(params[:id])
end
I also added in status as a boolean to help on the view for marking the checkbox. Would I then need to put something in the other_show method about the status?
If you want to "recreate" some sort of version control I suggest you use something like the audited. Instead of building your own. From your example and comments it seems you don't have a clear relation between all related (versions of) posts.
Using this gem, each change to the Post content (for example, if configured properly) would be stored as an audit.
Showing the differences is a different problem. That's usually called a diff and you can find gems that do it for you, for example: diffy
To show 2 different entities on one page you need to give posts_controller both ids.
Declare your show method like this:
def show
#original = Post.find(params[:id])
#compared = Post.find(params[:compared_id])
end
Correct route to this method will look like this:
/posts/:id?compared_id=:another_id
# Example: /posts/1?compared_id=2
To construct such a link in your view, you need to declare link_to method like this:
<%= link_to '1 <> 2', post_path(#post, compared_id: '2') %>
If you want to have a page where user can check 2 checkboxes for certain posts, you'll need to construct such href via Javascript.
But in fact I wouldn't suggest you to modify show method for such a task. It is better to use show method only for showing one entity from database. You can create another method, e.g. compare and pass both parameters there.
def compare
#original = Post.find(params[:original_id])
#compared = Post.find(params[:compared_id])
end
In routes.rb
resources :posts do
get 'compare', on: :collection
end
It will give you helper compare_posts_path, which will lead to /posts/compare and you'll need to pass original_id and compared_id to it, like this:
<%= link_to 'Compare', compare_posts_path(original_id: 'some_id', compared_id: 'some_another_id') %>
It will result to
/posts/compare?original_id=some_id&compared_id=some_another_id
I've got a table full of information at the moment, Ideally i need the information from a database table to be viewed via a link.
I only have the controller and some standard html (the html is just a h1 tag at the moment)
The HTML will be standard throughout like a template.
The way i'm seeing what i want in my head is the users will get a link which would be events_prev/{{id from DB here}} and depending on the ID the information on the page will be populated from the corrisponsing DB Row
Heres my controller
class Events::EventsPrevController < ApplicationController
def index
#events = Event.where(id: id)
end
def show
render :nothing => true
end
end
Sorry if its super confusing.
Welcome to rails.
Ok, there's a couple of things that will get you in the right directions. Firstly, you REALLY need to do a little reading to understand how the controller and the routes and the views are linked together in rails, that'll help you tons.
But moving on to your specific issues:
Parameters:
All data passed via a url (get, post, put, doesn't matter the method) is available in the controller in an array object called params - So that means when want to access the data the user submitted, you'll use something like
#event = Event.where(id: params[:id])
Routes:
It looks like you're trying to use the index page. In rails index is a RESTful route which generally points to a collection of model objects. The show route will point to an individual object so you should instead make your link point to the show path instead of the index path.
You can view the routes available on a model on a command line using:
bundle exec rake routes
An example of what your routes might look like:
prev_events GET /prev_events(.:format) prev_events#index
POST /prev_events(.:format) prev_events#create
new_prev_event GET /prev_events/new(.:format) prev_events#new
edit_prev_event GET /prev_events/:id/edit(.:format) prev_events#edit
prev_event GET /prev_events/:id(.:format) prev_events#show
PATCH /prev_events/:id(.:format) prev_events#update
PUT /prev_events/:id(.:format) prev_events#update
DELETE /prev_events/:id(.:format) prev_events#destroy
Link
Based on the routing table, you now should see that the link you need your users to click on might look like this (given that event is your object:
<%= link_to event.title, event_path(event.id) %>
or shortcutted
<%= link_to event.title, event %>
View
For the view this is entirely dependent on the data in the Event model. Since the data is stored in #event you'll simple use the attributes on the event model to render the html however use like, e.g.
<h3><%= #event.title %></h3>
<span><%= #event.start_time %></span>
You should read up on Rails controllers: by default the action index is used to show all of the records and what you're talking about should belong to the show action. The default routes take care of the id passing to your show action.
Index action is mean to show list of items in view and Show action is used to show a single item.
what you are doing in index is actually mean to be in show action.
Reason:
#events = Event.where(id: id)
this line will give u a single record in every case it means it should be in Show action.
your code should look like:
def show
#event = Event.find(params[:id])
[your logic: what you want to do with that #event]
end
Rails newbie here. This specific question has probably been asked before, if not here then on some other site, but after looking around a lot I wasn't able to find anything helpful because I lack the terminology to describe what I want to accomplish. I'm sorry if it comes across as trivial.
Basically I have a freshly created Rails project with a scaffold Item (generated by rails g scaffold Item [...attributes...]) and I want to create an additional page, similar to the index page, but instead of displaying all of the items I want the items to be filtered. So for the index page the part in the controller file looks like this
def index
#items = Item.all
end
and I want to know how to, instead, have some sort of controller for my other page (call it index2) that uses some find-like method only grabs the Items that have a certain attribute, e.g. are "red" in color:
def index2
#items = Item.find(color: "red") #all items that have red as their color attribute
end #are assigned to #items
How can I do this? And where can I find more manipulations (other than all(), first, second, ...) like this? Thank you for your patience.
You can add an action to your ItemsController
def red_items
#items = Item.where(color: "red")
end
you can use where for all the filters
You will have to add a view called red_items.html.erb to /app/views/items for the controller to render automatically. If you want to use index template, then just render the template explicitly in your new action
def red_items
#items = Item.where(color: "red")
render :template => "index"
end
Here is a link to Active Record Query Interface where you can find all possible query methods
For people that only want the question, here it is :
Is there a way to specify the folder to look in when you call render on an object? I don't want to specify the view, only the folder to look in.
And for people that want context :
I am working on an activity stream system (something that looks like google+/facebook).
I have "Activities", which are exactly like google+ feeds (or facebook, or whatever!). So, I have a simple loop that display each activities, which are bound to one of the following object (polymorphic) : User, Group, Comment, Note.
In my view that render an activity (views/activities/_activity.html.erb), I have
<%= render activity.object %>
where activity.object is a reference to the bound object (User, Group, Note, Comment). If it's a user, it goes to views/users/_user.html.erb and renders it. For a group, views/groups/_group.html.erb.
That works just fine. However, I come to the point where the rendering of a group in my activities should not be the same rendering as in the group list page. Is there a way to specify the folder to look in when you call render on an object? So that my :
<%= render activity.object %>
would become :
<%= render activity.object, :folder => 'views/activities/' %>
Note that I don't want to specify which view directly, as I don't want to do a case for each of the possible types of objects (User, Group, Note, Comment) in the activity. I want to to have the same behaviour as of right now, which means if it finds a views/activities/_user.html.erb, it would load any user in the activities with that view instead of the one in the views/users/_user.html.erb.
Thanks
I'm not aware of any folder type option, but when I do this I usually do:
<%= render "activities/#{activity.object.class.name.underscore}" %>
That would give you similar behaviour.
EDIT A good point below by Dominic, if your classes are nested in namespaces, you will have to include the appropriate structure.
i.e.
module Foo
class Bar < ActiveRecord::Base
end
end
# class.name is Foo::Bar, underscored is 'foo/bar'
<%= render "activities/#{activity.object_type.underscore}" %>
# will be in
activities/foo/_bar.html
In current Rails (3.2.9), you can define a to_partial_path method on your model to tell it where to look.
For example, you can do:
class User
def to_partial_path; "user"; end
end
Rails will then look for _user.html.erb relative to the view from which you're calling render.
My own approach, which I extracted in polymorphic_render gem - to add suffixes for special partials, but store that partial in resource folders.
In your case views/users/_user.html.erb will have very common user representation (which probably used in users list rendering), but views/users/_user_activity.html.erb will render special partial for user activity.
And inserting that partials is very simple, just <%= polymorphic_render activity.object, :activity %>
I have a Ruby/Rails app that has two or three main "sections". When a user visits that section, I wish to display some sub-navigation. All three sections use the same layout, so I can't "hard code" the navigation into the layout.
I can think of a few different methods to do this. I guess in order to help people vote I'll put them as answers.
Any other ideas? Or what do you vote for?
You can easily do this using partials, assuming each section has it's own controller.
Let's say you have three sections called Posts, Users and Admin, each with it's own controller: PostsController, UsersController and AdminController.
In each corresponding views directory, you declare a _subnav.html.erb partial:
/app/views/users/_subnav.html.erb
/app/views/posts/_subnav.html.erb
/app/views/admin/_subnav.html.erb
In each of these subnav partials you declare the options specific to that section, so /users/_subnav.html.erb might contain:
<ul id="subnav">
<li><%= link_to 'All Users', users_path %></li>
<li><%= link_to 'New User', new_user_path %></li>
</ul>
Whilst /posts/_subnav.html.erb might contain:
<ul id="subnav">
<li><%= link_to 'All Posts', posts_path %></li>
<li><%= link_to 'New Post', new_post_path %></li>
</ul>
Finally, once you've done this, you just need to include the subnav partial in the layout:
<div id="header">...</div>
<%= render :partial => "subnav" %>
<div id="content"><%= yield %></div>
<div id="footer">...</div>
Partial render. This is very similar to the helper method except perhaps the layout would have some if statements, or pass that off to a helper...
As for the content of your submenus, you can go at it in a declarative manner in each controller.
class PostsController < ApplicationController
#...
protected
helper_method :menu_items
def menu_items
[
['Submenu 1', url_for(me)],
['Submenu 2', url_for(you)]
]
end
end
Now whenever you call menu_items from a view, you'll have the right list to iterate over for the specific controller.
This strikes me as a cleaner solution than putting this logic inside view templates.
Note that you may also want to declare a default (empty?) menu_items inside ApplicationController as well.
Warning: Advanced Tricks ahead!
Render them all. Hide the ones that you don't need using CSS/Javascript, which can be trivially initialized in any number of ways. (Javascript can read the URL used, query parameters, something in a cookie, etc etc.) This has the advantage of potentially playing much better with your cache (why cache three views and then have to expire them all simultaneously when you can cache one?), and can be used to present a better user experience.
For example, let's pretend you have a common tab bar interface with sub navigation. If you render the content of all three tabs (i.e. its written in the HTML) and hide two of them, switching between two tabs is trivial Javascript and doesn't even hit your server. Big win! No latency for the user. No server load for you.
Want another big win? You can use a variation on this technique to cheat on pages which might but 99% common across users but still contain user state. For example, you might have a front page of a site which is relatively common across all users but say "Hiya Bob" when they're logged in. Put the non-common part ("Hiya, Bob") in a cookie. Have that part of the page be read in via Javascript reading the cookie. Cache the entire page for all users regardless of login status in page caching. This is literally capable of slicing 70% of the accesses off from the entire Rails stack on some sites.
Who cares if Rails can scale or not when your site is really Nginx serving static assets with new HTML pages occasionally getting delivered by some Ruby running on every thousandth access or so ;)
You could use something like the navigation plugin at http://rpheath.com/posts/309-rails-plugin-navigation-helper
It doesn't do sub-section navigation out of the box, but with a little tweaking you could probably set it up to do something similar.
I suggest you use partials. There are a few ways you can go about it. When I create partials that are a bit picky in that they need specific variables, I also create a helper method for it.
module RenderHelper
#options: a nested array of menu names and their corresponding url
def render_submenu(menu_items=[[]])
render :partial => 'shared/submenu', :locals => {:menu_items => menu_items}
end
end
Now the partial has a local variable named menu_items over which you can iterate to create your submenu. Note that I suggest a nested array instead of a hash because a hash's order is unpredictable.
Note that the logic deciding what items should be displayed in the menu could also be inside render_submenu if that makes more sense to you.
I asked pretty much the same question myself: Need advice: Structure of Rails views for submenus? The best solution was probably to use partials.
There is another possible way to do this: Nested Layouts
i don't remember where i found this code so apologies to the original author.
create a file called nested_layouts.rb in your lib folder and include the following code:
module NestedLayouts
def render(options = nil, &block)
if options
if options[:layout].is_a?(Array)
layouts = options.delete(:layout)
options[:layout] = layouts.pop
inner_layout = layouts.shift
options[:text] = layouts.inject(render_to_string(options.merge({:layout=>inner_layout}))) do |output,layout|
render_to_string(options.merge({:text => output, :layout => layout}))
end
end
end
super
end
end
then, create your various layouts in the layouts folder, (for example 'admin.rhtml' and 'application.rhtml').
Now in your controllers add this just inside the class:
include NestedLayouts
And finally at the end of your actions do this:
def show
...
render :layout => ['admin','application']
end
the order of the layouts in the array is important. The admin layout will be rendered inside the application layout wherever the 'yeild' is.
this method can work really well depending on the design of the site and how the various elements are organized. for instance one of the included layouts could just contain a series of divs that contain the content that needs to be shown for a particular action, and the CSS on a higher layout could control where they are positioned.
There are few approaches to this problem.
You might want to use different layouts for each section.
You might want to use a partial included by all views in a given directory.
You might want to use content_for that is filled by either a view or a partial, and called in the global layout, if you have one.
Personally I believe that you should avoid more abstraction in this case.