ruby on rails qr code implemetation - ruby-on-rails

Question

hi just trying to create a qr code in my rails website using sam vincents qr code generator https://github.com/samvincent/rqrcode-rails3....... first i added this code to a controller
class QrcodeController < ApplicationController
def qrcode
respond_to do |format|
format.html
format.svg { render:qrcode => #qrurl, :level => :l, :unit => 10, :color => black }
format.png { render :qrcode => #qrurl }
format.gif { render :qrcode => #qrurl }
format.jpeg { render :qrcode => #qrurl }
end
end
def options
{:qrcode => "http://helloworld.com", size => 4}
end
end
then i am not sure what to add in the view i tried this
<div class="Qrcode qr">
<h2>Qr code</h2>
<p><%= link_to "SVG", Qrcode_path("svg") %></p>
<p><%= link_to "PNG", Qrcode_path("png") %></p>
<p><%= link_to "JPEG", Qrcode_path("jpeg") %></p>
<p><%= link_to "GIF", Qrcode_path("gif") %></p>
would appreciate any help on how it works as their are not that many instructions online
im using ruby 1.9.3 and rails 4.0.1

Answer 1

I'm using rqrcode gem. It's pretty simple and you don't need to generate images for your qrcodes. The code is generated using tables and some css styles...
You can use this helper: /helpers/qrcode_helper.rb
module QrcodeHelper
require 'rqrcode'
def render_qr_code text, size = 3
return if text.to_s.empty?
qr = RQRCode::QRCode.new(text)
sizeStyle = "width: #{size}px; height: #{size}px;"
content_tag :table, class: "qrcode pull-right" do
qr.modules.each_index do |x|
concat(content_tag(:tr) do
qr.modules.each_index do |y|
color = qr.dark?(x, y) ? 'black' : 'white'
concat content_tag(:td, nil, class: color, style: sizeStyle)
end
end)
end
end
end
end
Into your view some_view.html.erb
<%= render_qr_code("MYCODE") %>
And you need to add style for your code qrcode.css.less
table.qrcode {
border-width: 0;
border-style: none;
border-color: #0000ff;
border-collapse: collapse;
margin-top: 100px;
margin-bottom: 12px;
td {
border-width: 0;
border-style: none;
border-color: #0000ff;
border-collapse: collapse;
padding: 0;
margin: 0;
width: 3px;
height: 3px;
&.black {
background-color: #000 !important
}
&.white {
background-color: #fff !important
}
}
}
My example it's working with Rails 3.

Answer 2

Here's a minimal example that avoids the need to write code to render each (x,y) "pixel" yourself.
In your controller:
def show
#qr = RQRCode::QRCode.new('https://stackoverflow.com/')
end
And then in your corresponding .html.erb view:
<p>
<%== #qr.as_svg %>
</p>
(Note that this uses <%==, not <%=; if you use the latter, you'll get the raw SVG XML source instead of a rendered SVG image.)
See the RQRCode docs for options that can be passed to .as_svg, and for other output options such as PNG.