toggle function

Question

my question is two functions are passed to toggle why.. and out side another function is there that is also confusing plz tell me

 $('#login a').toggle(function() {
    $(this)
      .addClass('active')
      .next('form')
      .animate({'height':'show'}, {
        duration:'slow',
        easing: 'easeOutBounce'
      });
  }, function() {
    $(this)
      .removeClass('active')
      .next('form')
      .slideUp();
  });
  $('#login form :submit').click(function() {
    $(this)
      .parent()
      .prev('a')
      .click();
  });

Answer 1

According to JQuery API documentation functions will be called on alternating clicks:

• first click - first function,
• second click - second function,
• third click - first function,
• fourth click - second function...

As for handler of submit button, it simulates click for anchor (a) element that is sibling to element that contains the button and is located before container element. Like this:

<a href="#">click will be simulated for this link</a>  
<div>  
    <input type="submit"/>  
</div>

Answer 2

The toggle() method takes two (or more) functions as arguments and calls one of them alternately each time the element is clicked.

Functions are first class citizens in Javascript: you can manipulate them like any other object, including passing them to other functions:

function foo(otherfunction)
{
    otherfunction();
}

function bar()
{
    window.alert("bar() was called.");
}

foo(bar);  // Ultimately calls `bar()`.