drupal/misc/drupal.js

365 lines
8.5 KiB
JavaScript

// $Id$
/**
* Only enable Javascript functionality if all required features are supported.
*/
function isJsEnabled() {
if (typeof document.jsEnabled == 'undefined') {
// Note: ! casts to boolean implicitly.
document.jsEnabled = !(
!document.getElementsByTagName ||
!document.createElement ||
!document.createTextNode ||
!document.documentElement ||
!document.getElementById);
}
return document.jsEnabled;
}
// Global Killswitch on the <html> element
if (isJsEnabled()) {
document.documentElement.className = 'js';
}
/**
* Make IE's XMLHTTP object accessible through XMLHttpRequest()
*/
if (typeof XMLHttpRequest == 'undefined') {
XMLHttpRequest = function () {
var msxmls = ['MSXML3', 'MSXML2', 'Microsoft']
for (var i=0; i < msxmls.length; i++) {
try {
return new ActiveXObject(msxmls[i]+'.XMLHTTP')
}
catch (e) { }
}
throw new Error("No XML component installed!");
}
}
/**
* Creates an HTTP GET request and sends the response to the callback function.
*
* Note that dynamic arguments in the URI should be escaped with encodeURIComponent().
*/
function HTTPGet(uri, callbackFunction, callbackParameter) {
var xmlHttp = new XMLHttpRequest();
var bAsync = true;
if (!callbackFunction) {
bAsync = false;
}
xmlHttp.open('GET', uri, bAsync);
xmlHttp.send(null);
if (bAsync) {
if (callbackFunction) {
xmlHttp.onreadystatechange = function() {
if (xmlHttp.readyState == 4) {
callbackFunction(xmlHttp.responseText, xmlHttp, callbackParameter);
}
}
}
return true;
}
else {
return xmlHttp.responseText;
}
}
/**
* Creates an HTTP POST request and sends the response to the callback function
*
* Note: passing null or undefined for 'object' makes the request fail in Opera 8.
* Pass an empty string instead.
*/
function HTTPPost(uri, callbackFunction, callbackParameter, object) {
var xmlHttp = new XMLHttpRequest();
var bAsync = true;
if (!callbackFunction) {
bAsync = false;
}
xmlHttp.open('POST', uri, bAsync);
var toSend = '';
if (typeof object == 'object') {
xmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
for (var i in object) {
toSend += (toSend ? '&' : '') + i + '=' + encodeURIComponent(object[i]);
}
}
else {
toSend = object;
}
xmlHttp.send(toSend);
if (bAsync) {
if (callbackFunction) {
xmlHttp.onreadystatechange = function() {
if (xmlHttp.readyState == 4) {
callbackFunction(xmlHttp.responseText, xmlHttp, callbackParameter);
}
}
}
return true;
}
else {
return xmlHttp.responseText;
}
}
/**
* Redirects a button's form submission to a hidden iframe and displays the result
* in a given wrapper. The iframe should contain a call to
* window.parent.iframeHandler() after submission.
*/
function redirectFormButton(uri, button, handler) {
// Make sure we have an iframe to target
createIframe();
// Trap the button
button.onmouseover = button.onfocus = function() {
button.onclick = function() {
// Prepare variables for use in anonymous function.
var button = this;
var action = button.form.action;
var target = button.form.target;
// Redirect form submission
this.form.action = uri;
this.form.target = 'redirect-target';
handler.onsubmit();
// Set iframe handler for later
window.iframeHandler = function () {
var iframe = $('redirect-target');
// Restore form submission
button.form.action = action;
button.form.target = target;
// Get response from iframe body
try {
response = (iframe.contentWindow || iframe.contentDocument || iframe).document.body.innerHTML;
if (window.opera) {
// Opera-hack: it returns innerHTML sanitized.
response = response.replace(/&quot;/g, '"');
}
}
catch (e) {
response = null;
}
// Recreate the iframe: re-using an old iframe can sometimes cause browser bugs.
createIframe();
response = parseJson(response);
// Check response code
if (response.status == 0) {
handler.onerror(response.data);
return;
}
handler.oncomplete(response.data);
}
return true;
}
}
button.onmouseout = button.onblur = function() {
button.onclick = null;
}
}
/**
* Adds a function to the window onload event
*/
function addLoadEvent(func) {
var oldOnload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
}
else {
window.onload = function() {
oldOnload();
func();
}
}
}
/**
* Adds a function to a given form's submit event
*/
function addSubmitEvent(form, func) {
var oldSubmit = form.onsubmit;
if (typeof oldSubmit != 'function') {
form.onsubmit = func;
}
else {
form.onsubmit = function() {
return oldSubmit() && func();
}
}
}
/**
* Retrieves the absolute position of an element on the screen
*/
function absolutePosition(el) {
var sLeft = 0, sTop = 0;
var isDiv = /^div$/i.test(el.tagName);
if (isDiv && el.scrollLeft) {
sLeft = el.scrollLeft;
}
if (isDiv && el.scrollTop) {
sTop = el.scrollTop;
}
var r = { x: el.offsetLeft - sLeft, y: el.offsetTop - sTop };
if (el.offsetParent) {
var tmp = absolutePosition(el.offsetParent);
r.x += tmp.x;
r.y += tmp.y;
}
return r;
};
function dimensions(el) {
return { width: el.offsetWidth, height: el.offsetHeight };
}
/**
* Returns true if an element has a specified class name
*/
function hasClass(node, className) {
if (node.className == className) {
return true;
}
var reg = new RegExp('(^| )'+ className +'($| )')
if (reg.test(node.className)) {
return true;
}
return false;
}
/**
* Adds a class name to an element
*/
function addClass(node, className) {
if (hasClass(node, className)) {
return false;
}
node.className += ' '+ className;
return true;
}
/**
* Removes a class name from an element
*/
function removeClass(node, className) {
if (!hasClass(node, className)) {
return false;
}
node.className = eregReplace('(^| )'+ className +'($| )', '', node.className);
return true;
}
/**
* Toggles a class name on or off for an element
*/
function toggleClass(node, className) {
if (!removeClass(node, className) && !addClass(node, className)) {
return false;
}
return true;
}
/**
* Emulate PHP's ereg_replace function in javascript
*/
function eregReplace(search, replace, subject) {
return subject.replace(new RegExp(search,'g'), replace);
}
/**
* Removes an element from the page
*/
function removeNode(node) {
if (typeof node == 'string') {
node = $(node);
}
if (node && node.parentNode) {
return node.parentNode.removeChild(node);
}
else {
return false;
}
}
/**
* Prevents an event from propagating.
*/
function stopEvent(event) {
if (event.preventDefault) {
event.preventDefault();
event.stopPropagation();
}
else {
event.returnValue = false;
event.cancelBubble = true;
}
}
/**
* Parse a JSON response.
*
* The result is either the JSON object, or an object with 'status' 0 and 'data' an error message.
*/
function parseJson(data) {
if (data.substring(0,1) != '{') {
return { status: 0, data: data.length ? data : 'Unspecified error' };
}
return eval('(' + data + ');');
}
/**
* Create an invisible iframe for form submissions.
*/
function createIframe() {
// Delete any previous iframe
deleteIframe();
// Note: some browsers require the literal name/id attributes on the tag,
// some want them set through JS. We do both.
window.iframeHandler = function () {};
var div = document.createElement('div');
div.id = 'redirect-holder';
div.innerHTML = '<iframe name="redirect-target" id="redirect-target" class="redirect" onload="window.iframeHandler();"></iframe>';
var iframe = div.firstChild;
with (iframe) {
name = 'redirect-target';
setAttribute('name', 'redirect-target');
id = 'redirect-target';
}
with (iframe.style) {
position = 'absolute';
height = '1px';
width = '1px';
visibility = 'hidden';
}
document.body.appendChild(div);
}
/**
* Delete the invisible iframe for form submissions.
*/
function deleteIframe() {
var holder = $('redirect-holder');
if (typeof holder != 'undefined') {
removeNode(holder);
}
}
/**
* Wrapper around document.getElementById().
*/
function $(id) {
return document.getElementById(id);
}