Ajax request via javascript

Hello Rubies,
      Have you tried AJAX request via javascript? Lets see the eg.

<script type="text/javascript">

  // Ajax without update parameter:
  function ajax_request(id){
    window._token = '<%= form_authenticity_token %>';
    var url = '/controller/action';
    var pars = 'id=' + id + '&authenticity_token=' + window._token;
    var myAjax = new Ajax.Request(url, {method: 'post', parameters: pars, onFailure: showFailure(), onSuccess: showSuccess() });
  }

  // Ajax with update parameter:
  function ajax_update_request(id){
    window._token = '<%= form_authenticity_token %>';
    var url = '/controller/action';
    var pars = 'id=' + id + '&authenticity_token=' + window._token;
    var myAjax = new Ajax.Updater('update_div_id', url, {method: 'get', parameters: pars, onFailure: showFailure(), onSuccess: showSuccess()});
  }

  function showSuccess(){
  }

  function showFailure(){
  }

</script>

Disable the link in rails via css or javascript

Hello Rubies,
      We have facility to disabled the link in rails 3 using :disable_with => 'Blah...'. But what about rails lowest version? We have one of the two possible option.

Either use:
1. <a href="javascript:;"> blah blah </a>
or
2. in css define
 .disabled_link{
   cursor: default;
   pointer-events: none;
 }
<a class='disabled_link'> blah blah </a>

Implement tab side out

Hello Guys,
      To implement tab slide out along with you application use the below code.


Download 2 javascript files:
1. jquery.min.js
2. tabSlideOut.v1.3.js


In your html page simply add below code.


<html>

  <head>
    <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js" type="text/javascript"></script>
    <script src="http://www.building58.com/examples/js/jquery.tabSlideOut.v1.3.js"></script>
  </head>
 

  <body>
    <script type="text/javascript">

      $(function(){
       jQuery('.slide-out-div').tabSlideOut({
 
         tabHandle: '.handle', //class of the element that will become your tab
         pathToTabImage: 'http://www.building58.com/examples/images/contact_tab.gif',
         //path to the image for the tab //Optionally can be set using css
         imageHeight: '190px', //height of tab image           //Optionally can be set using css
         imageWidth: '59px', //width of tab image            //Optionally can be set using css
         tabLocation: 'left', //side of screen where tab lives, top, right, bottom, or left
         speed: 300, //speed of animation
         action: 'click', //options: 'click' or 'hover', action to trigger animation
         topPos: '100px', //position from the top/ use if tabLocation is left or right
         leftPos: '20px', //position from left/ use if tabLocation is bottom or top
         fixedPosition: false //options: true makes it stick(fixed position) on scroll
       });
 
      });

     jQuery.noConflict(); // use this when prototype will be conflict with jquery.
 

    </script>

    <style type="text/css">
     
      .slide-out-div {
          padding: 20px;
          width: 250px;
          background: #ccc;
          border: 1px solid #29216d;
      }

    </style>

    <div class="slide-out-div">
      <a class="handle" href="javascript:;">Content</a>
      <h3>Contact Us</h3>
      <p>
        Click on here to contact us..blah..blah..
      </p>
    </div>
  </body>

</html>

Concat string via MY SQL & PSQL

Hey guys,

      Do you know there is little bit difference to concat the string  under MY SQL & PSQL?

mysql:

update posts set title = concat(title, 'Hey')

psql:

update posts set title = title || 'Hey'

Schedule cron job on linux

Hello Guys,

   Set cron job on linux to invoke at every 1 minute or daily base.

on command prompt:

crontab -e

add below lines

For every 1 minute:

 */1 * * * * cd /home/user/application_path && /home/user/.rvm/bin/rvm use ruby-1.9.2-p136 rake custom_task >> /home/user/crontab_errors.txt

For daily

0 0 * * * cd /home/user/application_path && /home/user/.rvm/bin/rvm use ruby-1.9.2-p136 rake reminder_email >> /home/user/crontab_errors.txt

rake jobs:work fails - delayed_job

 Hello Guys,

       Do you stuck with the problem to execute rake jobs:work during delayed_job implementation? than follow the below steps.

 Rake.rb

In your rails application's Rakefile add few lines.

begin
  gem 'delayed_job', '~>2.0.5'
  require 'delayed/tasks'

rescue LoadError
  STDERR.puts "rake gems:install` to install delayed_job"
end

Also if you want to use the script/delayed_job start command than add delayed_job under lib folder of rails application.

lib/delayed_job

#!/usr/bin/env ruby

require File.expand_path(File.join(File.dirname(__FILE__), '.', 'config', 'environment'))
require 'delayed/command'
Delayed::Command.new(ARGV).daemonize

Now, you do the rake -T to see that delayed_job task are also embed. Hope you will find useful support via this post.

Dygraph fails on IE 8

Hello Guys,
      Just discover the problem while loading dygraph on IE 8. There are possible scenarios for dygraph failure.

case 1. instanceof is not support
           replace instanceof with Object.prototype.toString.call()
           Line 500 of dygraph-utils.js replace
              typeof Node === "object" ? o instanceof Node :
           with
              typeof Node === "object" ? Object.prototype.toString.call(o) === Node :

case 2. canvas can't load

<!DOCTYPE html>
<meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7; IE=EmulateIE9">
<!--[if IE]><script src="excanvas.js"></script><![endif]-->
<!--[if lt IE 9]><script language="javascript" type="text/javascript" src="http://mycheckpoint.googlecode.com/svn-history/r95/trunk/dygraphs/excanvas.min.js"></script><![endif]-->

Hope above article will help you.