调整移动网站的图像大小，Ruby on Rails

Question

so I am working on a website that is a static scrollable one page, but for some reason it was deployed in ruby on rails. I am a noob in ror. There is one image in the html page that needs to resize whenever the site is loaded on a mobile device.

   <li><%= image_tag 'Main_logo.png', width: '700', height: '399' %></li>

Now I think I can do this in CSS, which means the client will resize and the full size image will always be downloaded. My question is how can I solve this issue using ror? I am sure ruby on rails has some server side capacity to fix this. Keep in mind I am new to ruby on rails

Thanks.

Answer 1

To your problem of resizing images, you can use the gem rmagick ( https://github.com/rmagick/rmagick )

The key line you probably need is thumb = img.resize_to_fit(75, 75) , and the document explaining it well is at http://www.imagemagick.org/RMagick/doc/comtasks.html

To your problem of detecting mobile browsers: SO post Detecting mobile browsers in Rails 3

Or if you want a super quick and dirty way, you can paste this into your controller: http://detectmobilebrowsers.com/