The around_* callback is called around the action and inside the before_* and after_* actions. For example:

class User
  def before_save
    puts 'before save'
  end

  def after_save
    puts 'after_save'
  end

  def around_save
    puts 'in around save'
    yield
    puts 'out around save'
  end
end

User.save
  before save
  in around save
  out around save
  after_save
=> true

jQuery – Select element cheat sheet

Note: elementid refers to the actual id of the select element. elementname refers to the actual name
of the select element.

e.g. <select id = “elementid” name = “elementname”></select>

Selecting an element(s) for further information refer to jQuery API Selectors

Basics:

Select element by id $(“#elementid”)

Select all select elements $(“select”)

Select all select elements by class $(“select.classname”)

Hierarchy:

Select all options from a select element $(“#elementid option”)

Basic Filters:

Select the first option $(“#elementid option:first”)

Select the last option $(“#elementid option:last”)

Select the option at a particular index (variant 1) $(“#elementid option:eq(2)”)

Attribute Filters:

Select all options that have a value attribute set $(“#elementid option[value]”)

Select element by name $(“select[name=elementname]”)

Form Filters:

Select the selected option $(“#elementid option:selected”)

jQuery core functionality, for further information refer to jQuery API Core

jQuery Object Accessors:

Execute a function on each matched element

e.g. $(“#elementid option”).each(function() {

        alert(“I am an option of #elementid”);

        })

Number of matched select elements

e.g. $(“select”).size() returns number of select elements on a page

Number of options in a particular select element $(“#elementid option”).size()

Select an option at a particular index (variant 2) $(“#elementid option”).eq(1)

Get the index of the selected option (variant 1) $("#elementid option").index($("#elementid option:selected")))

Select attributes, for further information refer to jQuery API Attributes

Attr:

Select an attribute from matched select element e.g. select name attribute $(“#elementid”).attr(“name”)

Set an attribute for matched select element e.g. set title $(“#elementid”).attr(“title”, “myselect”)

Remove an attribute from matched select e.g. remove title element $(“#elementid”).removeAttr(“title”)

Class:

Add a class to matched select element $(“#elementid”).addClass(“inputs”)

Remove a class from matched select element $(“#elementid”).removeClass(“inputs”)

HTML:

Get inner HTML of matched select $(“#elementid”).html()

Remove all options from matched select $(“#elementid”).html(“”)

Set all new options for matched select e.g. 

$("#elementid").html("<option value='1'>Some oranges</option><option value='2'>More Oranges</option><option value='3'>Even more oranges</option>")

Text:

Get the text of matched option e.g. $(“#elementid option:first”).text()

Get the selected text of matched select Returns text value of selected option $(“#elementid option:selected”).text()

Remove the text of matched option e.g. $(“#elementid option:last”).text(“”)

Set the text of a matched option e.g. $(“#elementid option:eq(2)”).text(“Purple”)

Value:

Get the value of the matched option item e.g. $(“#elementid option:first”).val()

Get the selected value of matched select Returns value attribute of selected option $(“#elementid”).val()

Set the value of a matched option e.g. $(“#elementid option:eq(2)”).val(“7”)

Set the selected element based upon value i.e. Sets the selected option to option with value 7

e.g. $(“#elementid”).val(“7”)

Set the selected element based upon text e.g.

$("#elementid").val("Oranges").attr("selected", "selected")

Traversing select attributes, for further information refer to jQuery API Traversing

Finding:

Get the index of the selected option (variant 2) $("#elementid option:selected").prevAll().size()

Manipulating select attributes, for further information refer to jQuery API Manipulation

Inserting Inside:

Add options to the end of select element

e.g. $("#elementid").append("<option

value='1'>Apples</option>")

Add options to the start of select element

e.g. $("#elementid").prepend("<option

value='0'>Before Apples</option>")

Inserting Outside:

Add options after selected index

e.g. $("#elementid option:eq(0)").after("<option

value='4'>Some pears</option>"

Add options before selected index

e.g. $("#elementid option:eq(3)").before("<option

value='5'>Some apricots</option>")

Replacing:

Replace items at a certain index

e.g. $("#elementid

option:eq(1)").replaceWith("<option

value='2'>Some apples</option>")

Removing:

Remove option at specified index $("#elementid option:eq(0)").remove()

Remove first option $("#elementid option:first").remove()

Remove last option $("#elementid option:last").remove()

Select element events, for further information refer to jQuery API Events

Event Helpers:

Function to call when an option is selected $("#elementid").change(function() {})

Getting values when an option is selected 

$("#elementid").change(function() {

  alert($(this).val());

  alert($(this).children("option:selected").text());

})

Select form submission, for further information refer to jQuery API AJAX

Event Helpers:

Serialize select element so it can be submitted or $("#elementid").serialize()

passed in URL Returns something like this: "elementname=1"

There are some steps to configure Server, Firewall and Apache .

Steps To Configure Server :
1. Lets know server type : $cat /etc/*-release
2. Update system : $ sudo apt-get update
3. Install git and curl : $sudo apt-get install curl git-core gitosis .
4. Now Install RVM : $ bash < <( curl https://rvm.beginrescueend.com/releases/rvm-install-head )
5. Make changes in /root/.bashrc file as mentioned after installing RVM .
     replace : [ -z "$PS1" ] && return
     with : if [[ -n "$PS1" ]] ; then
  and at the end of file add
    [[ -s "/usr/local/rvm/scripts/rvm" ]] && source "/usr/local/rvm/scripts/rvm"
    if
  After chnages use "su" on prompt .So that .bashrc file can be loaded with changes
6. Install Ruby depandencies for RVM: $ apt-get install build-essential bison openssl libreadline6 libreadline6-dev curl git-core zlib1g zlib1g-dev libssl-dev libyaml-dev libsqlite3-0 libsqlite3-dev sqlite3 libxml2-dev libxslt-dev autoconf libc6-dev ncurses-dev automake
7. Now RVM is ready to install ruby like : $ rvm install 1.9.2-p180
8. Install database server (say mysql) : $ sudo apt-get install mysql-server
9. Setup application in /var/www ( if www directory not exist then create it.)


Step to Configure firewall :
1. View entries in iptable : $ iptables -L
2. Allow ports : $ iptables -A INPUT -p tcp -dport ssh -j ACCEPT
   it can also be done by specifing port number : $ iptables -A INPUT -p tcp -dport 80 -j ACCEPT
3. TO allow ping : $ iptables -I INPUT 2 -p icmp -j ACCEPT
4. TO allow established sessions to receive traffic : $ iptables -I INPUT 2 -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
5. Save setting : $ sudo bash -c "iptables-save > /etc/iptables.rules"

Step to Configure apache :
1. Install apache : $ sudo apt-get install apache2
    apache's required files for changes will be available in /etc/apache2/ directory .
2. Install passenger gem to support ruby and rails on apache : $ gem install passenger
3. Now run : $ passenger-install-apache2-module
    This will suggest, what to do next.
4. Create a file in sites-available directory with any name you want . And copy content suggested in above step
  <VirtualHost *:80>......
      .....
      .....
  </VirtualHost>
  And make setting as required .
5. Remove the symbolic links for default from site-enabled.
6. Create symbolic links in site-enabled folder from newly created file in site-available.
7. Restart apache :/etc/init.d/apache2 start/stop/restart
8. Restart passanger after chnages in app : touch path_to_app/tmp/restart.txt


Rails 3 Problem with Passenger :
when gem 'paperclip', :git => 'git://github.com/lmumar/paperclip.git', :branch => 'rails3' is added to your Gemfile
then there will be some problem while you are running app . Try
$ bundle --deployment

#~ class Array

  #~ def reverse_iterate

    #~ current_index = self.size-1

    #~ while current_index >= 0

      #~ yield self[current_index]

      #~ current_index -= 1

    #~ end

  #~ end

#~ end

#~ 

#~ [2,4,6,8].reverse_iterate { |i| print "#{i} "}

class Array

  def each_anil &block

    yield self

  end

end

[2,4,6,8].each_anil {|p| puts p}