I'm wondering how to create a "shuffle" button in the header partial of my rails app that links to a random record. I have a "pins" table and each pin is a video.
I've searched through stackoverflow and couldn't figure out how to do it..
I think it had to do with the header partial doesn't work with the Pins controller/model.
When someone clicks the button it should link to something like this:
website.com/pins/13
Any help would be great thanks!
EDIT:
This is the code I have previously tried:
offset = rand(Model.count)
rand_record = Model.first(:offset => offset)
But I am new to rails and I wasn't sure where to put it. I tried putting it in the model and the controller and both didn't work.
Ok, so I'm assuming that you want a link to a random Model to be shown each time a user loads a particular page. Let's say that the page that shows this link is the ModelController#index action.
Since the randomization only happens when the page is initially loaded, you can do it in the controller action:
class ModelController < ActionController::Base
#other actions
def index
#any other index code
#random_model = Model.order('random()').first
end
end
Now, in your view, you can link to that model in the usual manner:
<%= link_to("Shuffle", #random_model, :class => "btn btn-small btn-warning") %>
Every time that the controller action executes, it will pick a Model at random, and include a link to that Model when it renders the page.
Edited to address:
"Is there anyway to make it work without putting the code in the index and show actions?"
Yes. You can actually load the model right in the view code. Normally, assigning it to an instance variable in the controller is the 'more correct' method, but as you point out, it leads to duplication of code. If this is something you want to include in multiple views, I would recommend making it a partial. Something like so:
views/shared/_shuffle.erb:
<%= link_to("Shuffle", Model.order('random()').first, :class => "btn btn-small btn-warning") %>
And then rendering that partial in any page you want to include a randomized link:
<%= render 'shared/shuffle' %>
Note that if you render this partial more than once in a page, the random model will be different for each link.
Related
I have a view that is handled by a simple controller:
class CountController < ApplicationController
def count
#index = 0
end
end
In my view I just added a button:
<%= link_to "Change next day", increase_count_path(#index), :class => 'btn' :remote => true %>
The request is being handled by a method I added in the CountController:
def increase_count
#index = params[:index].to_i + 1
end
After trying it, I saw that each time the request is being sent to /increase_count/0 , so this obviously doesn't update the variable as I'd like it to.
So my guess is, the 2 are not linked. The first one has its scope in the view, and the second one, from the increase_count method is visible in whatever javascript I would render from it.
How can I achieve this in Rails? The thing I was trying to achieve and ran into this was the following (simplified version): I have an array of 3 Strings. Firstly I display the first one. On click I would like to make an Ajax call, increment the index, and display the next string. But I ended up showing only the second one, because the next calls don't update the index.
Your AJAX call will indeed update the #index instance variable within the controller, however if you don't re-render the link then it will continue to use the initial value of #index.
Consider re-rendering the link within a JavaScript template.
E.g.
// inside increase_count.js.erb
// Fetch the link in question and re-render it
// The newly rendered link will use the updated value from the instance variable within the #increase_count action
// Generates the link
// Use the j helper to escape any JavaScript within the text
var link = "<%= j link_to("Change next day", increase_count_path(#index), :class => 'btn' :remote => true) %>";
// Select the link using jQuery and update it
$("...").html(link);
You may want to turn the link into a partial to avoid duplicating the code in the view and in the JS template. You'll also want to use a good selector to grab the link more easily.
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
So, I have search form, and search is avaliable obviously from any page.
I thought that it makes sense, that such action from application controller is placed in layouts/views folder.
But I just don't get- Rails doesn't see it. So I can't do this? How then should I provide action, avaliable from any page?
Code:
def tests_search
#tests=Test.test_search(params[:query])
respond_to do |format|
format.html
end
end
Route:
search_tests GET /search_tests(.:format) application#tests_search
Form:
<%= form_tag search_tests_path, {:id=>'test_search',:method => :get} do%>
Error:
Unknown action
The action 'tests_search' could not be found for ApplicationControllerr
You should create a new search controller. Use rails g controller search index which will create a search controller with a index action (you could also call the action something like result). Then add a search/_form.html.erb file in your search view folder, with the form:
<%= form_tag search_path, {:id=>'test_search',:method => :get} do |f| %>
and render this in your layout/application.html.erb where you want it to be:
<%= render "search/form" %>
This way you have a search form on any pages, that uses the SearchController to handle the search requests.
I would recommend using other controller to do this. It can be for example SearchController even if there will be only one method.
Notice that ApplicationController is controller that every other controller in application inherits from by default. So if it wouldn't be the case, it could make sense, but now every controller will inherit your test_search action, which is not desired.
If your search form will be a partial, then there is no difference whether this is in ApplicationController or in any other controller. You just have to point to right route.
Initially you have to explain yourself the flow. What you need is some partial which is rendered on all pages, and if a user adds some input to it and submits, he gets some output. Right? Good. So you start by creating a new partial somewhere in
app/views/shared/_search.html.erb
Then, you create your route in routes.rb to point to a controller's action. You don't have to place this in application_controller. Instead, create your search_controller.rb and create some action which responds to the form submission there.
Whenever you want to render your search form on other pages, you simply call render partial (more on that here) with something like
<%= render "shared/search" %>
This is good if you created the file above. Make sure your action exists and the name is correct, in your case it should be:
def test_search
...
end
Good luck.
UPDATE 3:
For anyone who reads this, this is why it wasn't working as expected in update 2 below: Passing a local variable to a partial that is rendered after the view has already loaded
If anyone knows how to solve that issue, let me know please.
UPDATE 2:
I updated the javascript with the quotation marks and it partially works...in the sense that the javascript is now functional and it will cause a string of text to appear on the page when I click the link as long as I have the partial only contain a string of text. However, when the partial includes the form fields code, something goes wrong.
If I just paste the following render code directly into the form in the new.html.erb view, it produces a new form section properly.
<%= render "add_round", f: f %>
However, when I try to include similar code in comps_helper.rb and then reference it from the link_to, it does not work:
In comps_helper.rb:
def addRound(f)
render "add_round", f: f
end
In new.html.erb:
<%= link_to "render it!", addRoundLink_path, remote: true %>
<div id="some_id"></div>
And I changed addRoundLink.js.erb to:
$("#some_id").html("<%=j addRound(f) %>"); #Is this the correct change to have made here?
Clicking the link_to link does nothing in that case.
Any thoughts?
UPDATED CODE:
Thanks for the reply. I've made the following changes and it still does not appear to be working. The link appears at the bottom of the form but when clicked does not change anything. What am I missing?
routes.rb:
resources :comps
match '/new_competition', :to => "comps#new"
get "/addRoundLink" => "comps#addRoundLink", :as => :addRoundLink
Note: I included the other 2 lines related to "comps" just in case those would cause an issue.
comps_controller.rb:
def addRoundLink
respond_to do |format|
format.js
end
end
comps_helper.rb:
def addRound
render "add_round"
end
addRoundLink.js.erb:
$("#some_id").html(<%=j addRound %>);
comps/new.html.erb:
<%= link_to "render it!", addRoundLink_path, remote: true %>
<div id="some_id"></div>
Thanks.
ORIGINAL QUESTION
First off, I'm new to rails. I've read and tried many solutions to similar questions but nothing has worked so far.
I created a form with rails form_for and fields_for. The form creates a new competition (comp). The competition has many rounds. The top half of the form (the form_for section) accepts the details about the competition as inputs and the bottom half of the form accepts details about each round (the fields_for section). The form works perfectly in this basic format.
I took all the code that is in the fields_for section and put it into a partial. My plan was to then create a "add new round" link to the bottom of the form that would simply display the partial above the link each time the link is pressed. This would add a new section to the form for a new round and allow the user to input as many rounds as they'd like. This is the part that I am struggling to make work.
I added this code to my comps_helper:
def addNewRound
render "add_round"
end
This renders the file /views/comps/_add_round.html.erb.
My question is: how do I get this to render in the form when a link is clicked. As far as I can get with the research I have done is:
<%= link_to "Add new round", { }, :remote => true %>
I don't exactly know what is supposed to go in the {} that will execute the addNewRound method. And I don't know what, if anything, I need to add to my comps_controller file.
Thanks so much for the help.
You have to create an action in your controller
app/controllers/some_controller.rb
def hello
respond_to do |format|
format.js
end
end
and define a route to this action.
routes.rb
get "/hello" => "some#hello", :as => :hello
then create a link to this action like that:
<%= link_to "render it!", hello_path, remote: true %>
<div id="some_id"></div>
When you click this link it will find its way to your action and respond with js(javascript) because we told action to respond with only js.
At the end render the partial to anywhere you want in your view(*in this example to the some_id div*)
app/views/some/hello.js.erb
$("#some_id").html("<%=j addNewRound %>");
WARNING: Creating dynamic forms is a pain. You will face a lot of problems (like setting different ids for new form elements etc...). I highly recommend you to use ryan bates nested_form gem
As my first Rails app, I'm trying to put together a simple blog application where users can vote on posts. I generated the Blogpost scaffold with a integer column (entitled "upvote") for keeping track of the vote count.
In the Blogpost model, I created a function:
def self.voteup
blogpost.upvote += 1
end
On the Blogpost index view, I'd like to create a link that does something like:
link_to "Vote up" self.voteup
But this doesn't seem to work. Is it possible to create a link to a method? If not, can you point me in the right direction to accomplish this?
What you are trying to do goes against the MVC design principles. You should do the upvoting inside a controller action. You should probably create a controller action called upvote. And pass in the post id to it. Inside the controller action you can retrive the post with the passed in ID and upvote it.
if you need serious voting in your rails app you can take a look at these gems
I assume that you need to increment upvote column in blogspots table. Redirection to a method is controllers job and we can give links to controller methods only. You can create a method in Blogposts controller like this:
def upvote_blog
blogpost = Blogpost.find(params[:id])
blogpost.upvote += 1
blogpost.save
redirect_to blogpost_path
end
In your index page,
<% #blogposts.each do |blogpost| %>
...
<%= link_to "Vote up", :action => upvote_blog, :id => blogpost.id %>
...
<% end %>
You can not map Model method to link_to in view. you can create an action in controller to access the Model method and map it using link_to, also if the action is other than CRUD, then you should define a route for the same in route.rb