Is there any rails QR code plugin for Rails 3? - ruby-on-rails-3

I want to generate QR code for my application which is going to run in Rails 3.0,
Is there any plugin available for that ?
Thanks in Advance,
Jak.

You can use Google's Chart API
def generate_qr_image( url )
raw "http://chart.apis.google.com/chart?chs=150x150&cht=qr&chl=#{url}&choe=UTF-8"
end

I think Google changed the api end point.
This worked for me:
= image_tag "https://chart.googleapis.com/chart?chs=150x150&cht=qr&chl=#{url}&choe=UTF-8"

As I understand it, anything based on google charts is deprecated, so not a long term solution.
I've used both the rqrcode gem and one of the many javascript encoders.

I Agree with TrAvid but it won't work, just need a small minute change,
Just assign #url="www.google.com" in the controller and then use this #url in View as
<%= image_tag "https://chart.googleapis.com/chart?chs=150x150&cht=qr&chl=#{#url}&choe=UTF-8" %>
It worked for me great.

I use the rqrcode_png that allow you to save the code as an image or do it like a table. It also let you display the image without saving it.
Here is an example of how save the image
qr = RQRCode::QRCode.new( 'your string', :size => 1, :level => :h )
image = qr.to_img.resize(250,250)
image.save('name.png')
or if you don't want to save it you can
qr = RQRCode::QRCode.new( 'your string', :size => 1, :level => :h )
#png = qr.to_img.resize(250,250).to_data_url
and then in your view <%= image_tag #png %>

Related

Showing Link in Text Field in Rails

In my Rails 3.1 app, I have a text field for comments and I want to be able to allow people to include clickable links (instead of just the url showing as plain text), as well as having the text field recognize when a user had line breaks in their text field (without the user adding html). How can I do this?
This works for showing a link if a user puts the html for a href:
<%= simple_format(#user.description) %>
And this works for recognizing and displaying the line breaks from carriage returns in the text_field:
<%= h(#user.description).gsub(/\n/, '<br/>').html_safe %>
However, I haven't figured out how to do both, together.
How about this?
#Doesnt work in this case
#<%= simple_format( h(#user.description).gsub(/\n/, '<br/>') ).html_safe %>
EDIT:
Seems like you need auto_link function to achieve this. Though it is removed from rails 3.1 it is available as a gem. So if you are using rails 3.1 or later you need to get this from a separate gem
#in Gemfile
gem "rails_autolink", "~> 1.0.9"
#in application.rb
require 'rails_autolink'
#Run
bundle install
#now in you view use it like
<%= h auto_link(simple_format(text)) %>
auto_link not only converts urls but also email addresses in clickable link. Get the document here.
Reference Links:
http://rubygems.org/gems/rails_autolink
http://apidock.com/rails/ActionView/Helpers/TextHelper/auto_link
Use the Rinku Gem
Link is here.
It brilliantly solves the problem. Enjoy!

How display image during pdf generation using wicked_pdf

i am using wicked_pdf and generating pdf of users records.image tag is not working when pdf is generate.So i use this trick and write this code in application helper.
def pdf_image_tag(image, options = {})
options[:src] = File.expand_path(Rails.root) + '/public' + image
tag(:img, options)
end
and in my view i call like this
<%= pdf_image_tag(#image.snap.url(:thumb)) unless #image.blank? %>
This is working fine for chrome and display image perfectly but not for other browsers.
Can any one give better suggestion.
Thanks....
Use the built-in helper wicked_pdf_image_tag
<%= wicked_pdf_image_tag(#image.snap.url(:thumb)) unless #image.blank? %>

Correct way to share a view in the index page

I'm a Ruby-on-Rails newbie, just starting out.
I have an MVC called "account_types", generated via scaffold to produce:
controllers/account_types_controller.rb
helpers/account_types_helper.rb
models/account_type.rb
views/account_types/_form, edit, index etc...
Going to localhost:3000/account_types gives me the index view.
What I'd like to do is display the same data as selected from the account_types index method in the application index page as a list.
I wrote a new view called account_types/_list.html_erb as follows:
<ul>
<% #account_types.each do |account| %>
<li><% account.label %></li>
<% end %>
</ul>
I then edited home/index.html.erb (This is based on examples given in other questions on SO):
<%= render :partial => 'account_types/list', :module_types => #module_types %>
However I get
undefined method `each' for nil:NilClass
and the error displays the code from account_types/_list.html.erb where I've written
<% #account_types.each do |account| %>
The scaffolded views work fine, why aren't mine?
Are partials the right thing to use here?
Thanks in advance.
What is the correct way to define an application-wide partial and its variables in rails says to use a before_filter on ApplicationController.
You pass :module_types to partial, but use account_types. As I can see you just need to change your index.html.erb to:
<%= render :partial => 'account_types/list', :account_types => #module_types %>
You can use partials for this if you want, though it would be unnecessary in this case as far as I can tell (they are for sharing chunks of code between several views). In order to get this code to work you'll need to define #account_types in your controller with something like
#account_types = AccountType.all
You can see exact line in your account_types_controller.rb under index action. :module_types => #module_types is not necessary here, since I doubt you defined #module_types either and you don't use module_types in your partial at all.
It's obvious, that you don't understand how Rails works, so I suggest reading through a good tutorial (like this one) before you proceed with whatever you have in mind.

How do I make a settings configuration page for the rails-settings gem?

I just discovered the rails-settings gem and now I need to make an admin page that lets me edit the setting values. How would I make a settings controller with an edit view that can change these dynamic app wide settings?
I haven't used this gem but it seems like it should be fairly straight forward. Since it uses a database backed model, you would simply create a controller as normal:
rails g controller Settings
From here you would define your index action to gather all your individual settings for display in the view:
def index
#settings = Settings.all
end
Then in the view you can setup a loop to display them:
<% #settings.each do |setting| %>
<%= setting.var %> = <%= setting.value %>
<% end %>
As far as editing ... this might be a bit tricky since by default rails would expect you to submit only one setting at a time to edit. You could do it this way but unless you implement the edit with ajax it might be tedious and non-intuitive.
Another way would be to set up your update method to accept all the individual settings at once, loop through and update each one with new values. It might look something like this:
// The /settings route would need to be setup manually since it is without an id (the default)
<%= form_tag("/settings", :method => "put") do %>
<% #settings.each do |setting| %>
<%= label_tag(setting.var, setting.var) %>
<%= text_field_tag(setting.var, :value => setting.value) %>
<% end %>
<%= submit_tag("Save Changes") %>
<% end %>
This should output all of the settings (given they have been assigned to the #settings variable) with the var name as the label and the current value as the text field value. Assuming that the routing is setup, when you submit this form the action that receives it should all the new settings in the params variable. Then you can do something like this in the action:
def update
params.each_pair do |setting, value|
eval("Settings.#{setting} = #{value}")
end
redirect_to settings_path, :notice => 'Settings updated' # Redirect to the settings index
end
This may not be the best way depending on how often you edit the settings and how many settings you have...but this is a possible solution.
I was looking for some suggestions for this and found another answer to this that is very simple and elegant, for anyone looking for this later. It just sets up dynamic accessors in your model, allowing your form to have settings fields just like your normal attributes. An example can be found in the original answer:
How to create a form for the rails-settings plugin

Beginner struggling with update_attribute command

I am in the process of trying to use the update_attribute command, but struggling to get it working (at all) and hoped someone could point me in the right direction?
I have previously posted a question about this issue, it was very useful in terms of giving a feel for the mechanics of what is going on, but unfortunately it didn't actually get it working.
I have a database of items (Items), which among other things contains ':item_name', ':click_count' and ':external_url'.
Currently I have a view (Showselecteditems) in which there is a list of all the items, when a user clicks on an item name, they are directed to the appropriate external url. This works using the code:
<%= link_to selecteditem.item_name.to_s, selecteditem.external_url %>
I would now like to add the ability to count the number of times a particular item name has been clicked on (i.e. in total for all users, not individual users) and therefore the number of times each external url has been visited in order to work out which is most popular.
Reading around, I believe i need to modify the code above to something of the form:
<%= link_to selecteditem.item_name.to_s, selecteditem.external_url, {:controller => params[:controller], :action => clickcountplusone, :identifier => selecteditem.item_name} %>
And need to define this function somewhere - it seems to only be found if located in 'application_helper'?
def clickcountplusone
clickeditem = Items.find(params[:identifier])
clickeditem.update_attribute(:click_count, clickeditem.click_count + 1)
rescue ActiveRecord::RecordNotFound # to avoid error if no identifier value
end
Needless to say, I cannot get this to work... My question is therefore, how can I set things up correctly so that when the link is clicked on the count is incremented? The other common problem people seem to report is that the number will be incremented each time the page is refreshed, which I would like to avod if possible.
Previously people have suggested adding to the 'show' section of the 'Items' controller, however, i don't know how this would work as the links are being clicked on the Showselecteditems view page, not the database itself where you get the show, edit, destroy commands. Any advice greatly appreciated.
This
<%= link_to selecteditem.item_name.to_s, selecteditem.external_url, {:controller => params[:controller], :action => clickcountplusone, :identifier => selecteditem.item_name} %>
will not point user to the some_controller#clickcountplusone, because you already specified an external link.
The easiest way to do this job is to modify your link_to like:
<%= link_to selecteditem.item_name.to_s, {:controller => params[:controller], :action => clickcountplusone, :identifier => selecteditem.item_name} %>
And then to modify your actions source:
def clickcountplusone
clickeditem = Items.find(params[:identifier])
redirect_to clickeditem.external_url if clickeditem.update_attribute(:click_count, clickeditem.click_count + 1)
rescue ActiveRecord::RecordNotFound # to avoid error if no identifier value
end