I would like to use lambda as a parameter for link_to for the code below: edit.html.erb
<h2>Edit customer info</h2>
<%= render 'form' %>
<%= link_to(#return_to) do %>
Back
step_back()
<% end %>
Here is the def for step_back:
#return link for previous page in page step
def step_back
session[:page_step] -= 1
end
The problem with the code above is that the step_back() is executed as soon as the edit.html.erb is loaded. Actually the step_back should only be executed when the user clicks the Back link. I figure that only lambda can accomplish this.
Any thoughts?
Your options are limited since you're interacting with the session.
You're getting that #return_to from somewhere; it'd probably be easiest to call an action that gets the same data and redirects to it, and does the same session manipulation.
See about writing your step_back() function in javascript and attaching it to an onClick html attribute on an tag instead of using the link_to rails helper
Then also .preventDefault() the event with javascript if you don't want the link to go anywhere, or to '#'
This will allow the code to execute on the click event in the browser and not during asset compilation before the page is served.
Related
I have an application which requires visitors to fill out a form and then it redirects to a second page. The client does not want to require visitors sign up to view this page, only to fill out the form.
The way I am attempting to do this is by creating a session variable when the page is visited and then checking to see if the variable exists before the next page is accessible. Is it possible to delay the creation of the session variable until the submit action is processed? If so what would that look like?
Also, can anyone think of a better way to do this? Sorry, this is probably a dumb question.
The session cookie would be declared after the first submit.
I presume the first submit will load up a controller#action in which you'll then redirect to the next page. Just set the session in there:
#app/views/forms/1.html.erb
<%= form_tag form_1_submit_path do %>
...
<% end %>
This will allow you to do the following:
#app/controllers/forms_controller.rb
class FormsController < ApplicationController
def form_1_submit
session[:value] = params[:value]
redirect_to form_2
end
end
Thus you'll have session[:value] all set and ready to use on the next form:
#app/views/forms/2.html.erb
<%= form_tag .... do %>
<%= text_field_tag :test, value: session[:value] %>
<% end %>
Is it possible to fire up an custom action when user clicks 'Search' button on search form?
There is an mechanism in our app to save every URL the app has hit. In our search form, when clicking 'Search' button, there will bring up the search result page. The problem is that the URL for the search result form was not saved. The Back button brings back the search page (for setup search params) instead of the search result page (because its URL was not saved).
Here is the search form for model configs:
<h4>Search Form></h4>
<%= simple_form_for #config, :method => :get, :url => search_result_configs_path do |f| %>
<%=render :partial => 'search_params', :locals => {f: f} %>
<%= f.button :submit, t('Search') %>
<% end %>
The URL for the search result looks like this (with the search params set by user) after user clicks Search button:
http://localhost:3000/configs/search_results?utf8=%E2%9C%93&engine_config[start_date_s]=&engine_config[end_date_s]=&engine_config[engine_id_s]=1&engine_config[argument_name_s]=&engine_config[commissioned_s]=&commit=%E6%90%9C%E7%B4%A2
This is the URL we would like the app to remember. We figure we need custom action triggered when a user clicks 'Search' button. Is it possible?
Route
Firstly, calling a custom application is actually quite a simple process - you just need to call its route:
#config/routes.rb
resources :search do
collection do
get :custom_action
end
end
This will allow you to use the likes of form_tag to call the custom route:
#app/views/your_controller/view.html.erb
<%= form_tag search_custom_action_path, method: :get do %>
...
<% end %>
--
Form
Secondly, you're using simple_form for your search form.
This is completely fine, but the problem you have here is that when you use this, it has to have a ActiveRecord object to populate the form with. This is probably where you're getting confused, as to do this, you need ot make sure #config is available every time you load that form, which I imagine can be a lot.
We've created a search form here:
Although in Rails 4, we used a form_tag for this form, as it allowed us to create & display the form where-ever we need in the app. This allows us to pass the required params through the form & access them on the other side
--
Params
You mention you want to "save the URL" - what do you mean by this?
Surely you'd prefer to save the params?
If this is true, the way to do this is actually relatively simple - you'll get access to the params hash in your controller when you send the request through:
#app/controllers/your_controller.rb
Class YourController < ApplicationController
def custom_action
params[:your_param] #-> this is accessible here
end
end
The bottom line is if you wanted to save the query strings, you'll have to create a model called Search or similar, allowing you to pass the params through when you process the custom action in your controller, just like you would any other ActiveRecord object
An apartment_listing has many reviews, and a review belongs to an apartment_listing.
In the file views/apartment_listings/show.html.erb, I show a list of reviews for that particular apartment_listing. These reviews are generated with the partial view apartment_listings/_review.html.erb like so:
<%= render :partial => "review", :collection => #apartment_listing.reviews %>
In _review, I want to have a button that, when pressed:
Increments that review's helpful_count attribute.
Makes it so that it cannot be pressed again while in the same browser - probably using cookies.
I feel like the former shouldn't be too hard to figure out, but it's got me beat. I'm really not sure where to start with the second goal.
EDIT: I managed to update the review's helpful_count attribute with this code in apartment_listings/_review.html.erb:
<%= form_for review, :method => :put, :remote => true do |f| %>
<%= f.hidden_field :helpful_count, value: (review.helpful_count + 1) % >
<%= f.submit 'Helpful?' %>
<% end %>
However, I'm not sure if this is the best way to do it, and I'd like to be able to disable the button after it is clicked.
Your code for updating helpful_count has the potential for problems. Imagine two users have loaded an apartment on their web page. One of them marks it helpful, and the next one does as well. Since when they initially loaded the page, helpful_count was the same, after both of them click helpful, the count will only be incremented by one: it would be updated twice to the same value.
Really, you want to create a new action, probably under the reviews resource for an apartment. That action could use ActiveRecord's increment method to update the helpful_count (technically there's still a race condition in increment!, you'd encounter it much less often) http://apidock.com/rails/ActiveRecord/Persistence/increment%21
Cookies seem like a reasonable solution for the latter problem. Simply bind to submit on the form with jQuery, and create the cookie in the handler.
What does the code look like in your reviews controller? More experienced RESTful coders might be able to speak more coherently on this, but the way I see it, incrementing the helpful_count attribute should be an action sent to the reviews controller. That way, you can create a link that performs the action asynchronously.
For example, inside _review.html.erb:
<% collection.each do |review| %>
<%= link_to "Mark as Helpful", "/apartment_listing/#{#apartment_listing.id}/reviews/#{#review.id}/incHelpful?nonce=#{SecureRandom.rand(16)}", :remote => true, :method => :put %>
# ... Do something cool with your review content ...
<% end %>
Inside your ReviewsController class:
def incHelpful
unless params[:nonce] == session[:nonce][params[:id]]
#review = Review.find(params[:id])
#review.helpful_count += 1
#review.update_attributes(:helpful_count)
session[:nonce][params[:id]] = params[:nonce]
end
render :nothing
# Optionally return some javascript or JSON back to the browser on success/error
end
Inside /config/routes.rb:
put "apartment_listing/:apart_id/reviews/:id/incHelpful" => "reviews#incHelpful"
The main idea here is that actions that edit a resource should use the PUT http method, and that change should be handled by that resource's controller. Rails' built-in AJAX functions are engaged by setting :remote => true inside the link_to helper. The second concept is that of a nonce, a random value that is only valid once. Once this value is set in the user's session, subsequent requests to incHelpful will do nothing.
I'm working on a small picture application. That I'm trying to do is build a counter to track how many times each image is clicked.
Right now I have in my view:
<% #galleries.each do |g| %>
<% for image in g.images %>
<div id="picture">
<%= render 'top_nav'%>
<%= link_to g.source, :target => true do %>
<%= image_tag image.file_url(:preview) %>
<% g.vote %>
<% end %>
<%= will_paginate(#galleries, :next_label => "Forward", :previous_label => "Previous") %>
</div>
Obviously this doesn't work, as the g.vote executes every time it's rendered, not clicked. Here's the vote method in my model:
def vote
self.increment!(:score)
end
I'm looking for a solution to run the vote method only when the image above is clicked. The links are to external resources only, not to a show action. Should I be building a controller action that's accepts a post, executes the vote, then redirects to the source?
Anyway, looking for some ideas, thanks.
I've done something similar, but keeping a count of how many times a Download link was clicked. This was awhile ago and I didn't know about Ajax at the time, but now I would recommend using jQuery (a great library in my opinion, but you could use something else) and do an Ajax call when the image is clicked that would execute some controller action which would increment that vote.
The other way, which is what I did in my scenario, and is what you talked about there, is creating a custom action in the controller that accepts a post. But I have to ask as well, does clicking on the image do something else in the behaviour of your website? For example, if when you click the picture, another random image is supposed to come up, that means you'll already have an action to load a new image and it be easy to stick the vote up in there before showing a new image. Otherwise you'd have to create the new controller action. If that's the case, the Ajax would be more efficient as the user wouldn't see a momentary flash as the page was refreshed (especially bad if the refresh time is long).
I am using Ruby on Rails 3 with Prototype/Scriptaculous and I am trying to update a 'div' content after that ActiveRecord values are changed, without reload the page.
In the "edit.html.erb" I have:
...
<div id="test_id">
<%= #account.name.to_s %>
</div>
<%= link_to_function( "Make test" ) do |page|
page.replace_html :test_id, #account.name.to_s
end %>
...
Before clicking on "Make test" I update the '#account.name' value, even via AJAX. Then, clicking on "Make test", the template doesn't changes.
These are steps:
I show the page
I update '#account.name' via AJAX
I click on "Make test"
'div' with 'id="test_id"' doesn't change!
What am I doing wrong?
P.S.: I think that #account is not reloaded in the page, also if his values are changed in the database. If so, what should I do?
I have seen the Railscasts "AJAX with RJS" and I followed an example in that (it is like the my), but it doesn't work for me.
If you have rendered edit.html.erb when the value of #account.name is "George", the HTML will remain the same (with the value "George") until you refresh it. Your call to link_to_function is, on page load, rendering an html link that calls javascript that replaces the inner html of the "test_id" div with 'George'. Unless you replace that HTML, it will always replace the inner html of that div with 'George'.
It's hard to recommend a solution without knowing exactly what you'd like to do...
updated to have more detail:
If you are making an AJAX call that changes the value of the account name on the server to "Fred", and want that change to appear on the page, you should refresh the parts of the page that use that value in that same AJAX call (that same controller action).
Your link_to_function generates HTML like this (if #account.name was 'George' when the page was rendered):
<a onclick="try { Element.update("test_id", "George"); ... >Make test</a>
It is not an ajax call, it is just a link that executes javascript. If you want to make it an ajax call that finds the latest value of the account name and refreshes the test_id div, do something like this:
<%# you need prototype included, but it should probably be in application.rhtml %>
<%= javascript_include_tag "prototype.js" %>
<div id="test_id">
<%= #account.name.to_s %>
</div>
<%= link_to_remote "Make test", :url => { :controller => "account", :action => "change_name" } %>
The 'Make test' link will now perform an AJAX call to the 'change_name' method in the 'account' controller. This method would look something like this:
def change_name
# here you would load the account from the db; I'm cheating
#account = Account.new(:name => "Fred")
render :update do |page|
page.replace_html :test_id, :text => #account.name.to_s
end
end