Drupal 6 JavaScript and jQuery - Ebook-Cours.com

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Chapter 3
All we do here is check to see if the height of the current element is higher than
the current highest (again, 100px by default). If it is higher, then the value of
stickyHeight is assigned to highest. All we're doing, then, is finding the highest
element and setting highest to that element's height.
There is one point of interest here. The highest variable is local to the init()
function, and is declared outside of the anonymous function declaration. Doesn't
it seem like this variable ought to be out of scope for the function inside our
each() loop?
Yet, as the previous example shows, it is still accessible inside of the function's body.
This works because in JavaScript, functions inside other functions retain access to
the variables of their parent functions. In other words, if function a() (the outer
function) encloses the definition of function b() (the inner function), then function
b() will have access to all of function a()'s local variables.
By the time the each() function returns, highest should be set to the pixel height of
the highest sticky node that we will display.
We're ready to move onto the next part of the init() function:
StickyRotate.init = function() {
var stickies = $(".sticky");
};
// If we don't have enough, stop immediately.
if (stickies.size() 0) {
return;
}
var highest = 100;
stickies.each(function () {
var stickyHeight = $(this).height();
if(stickyHeight > highest) {
highest = stickyHeight;
}
});
stickies.hide().css('height', highest + 'px');
StickyRotate.counter = 0;
StickyRotate.stickies = stickies;
stickies.eq(0).fadeIn('slow');
setInterval(StickyRotate.periodicRefresh, 7000);
This material is copyright and is licensed for the sole use by Richard Ostheimer on 18th June 2009
2205 hilda ave., , missoula, , 59801