https://www.chersi.it/drupal/misc/drupal.js

1// $Id: drupal.js,v 1.22.2.1 2006/05/29 14:23:32 killes Exp $
2
3/**
4 * Only enable Javascript functionality if all required features are supported.
5 */
6function isJsEnabled() {
7  if (typeof document.jsEnabled == 'undefined') {
8    // Note: ! casts to boolean implicitly.
9    document.jsEnabled = !(
10     !document.getElementsByTagName ||
11     !document.createElement        ||
12     !document.createTextNode       ||
13     !document.documentElement      ||
14     !document.getElementById);
15  }
16  return document.jsEnabled;
17}
18
19// Global Killswitch on the <html> element
20if (isJsEnabled()) {
21  document.documentElement.className = 'js';
22}
23
24/**
25 * Make IE's XMLHTTP object accessible through XMLHttpRequest()
26 */
27if (typeof XMLHttpRequest == 'undefined') {
28  XMLHttpRequest = function () {
29    var msxmls = ['MSXML3', 'MSXML2', 'Microsoft']
30    for (var i=0; i < msxmls.length; i++) {
31      try {
32        return new ActiveXObject(msxmls[i]+'.XMLHTTP')
33      }
34      catch (e) { }
35    }
36    throw new Error("No XML component installed!");
37  }
38}
39
40/**
41 * Creates an HTTP GET request and sends the response to the callback function.
42 *
43 * Note that dynamic arguments in the URI should be escaped with encodeURIComponent().
44 */
45function HTTPGet(uri, callbackFunction, callbackParameter) {
46  var xmlHttp = new XMLHttpRequest();
47  var bAsync = true;
48  if (!callbackFunction) {
49    bAsync = false;
50  }
51  xmlHttp.open('GET', uri, bAsync);
52  xmlHttp.send(null);
53
54  if (bAsync) {
55    if (callbackFunction) {
56      xmlHttp.onreadystatechange = function() {
57        if (xmlHttp.readyState == 4) {
58          callbackFunction(xmlHttp.responseText, xmlHttp, callbackParameter);
59        }
60      }
61    }
62    return xmlHttp;
63  }
64  else {
65    return xmlHttp.responseText;
66  }
67}
68
69/**
70 * Creates an HTTP POST request and sends the response to the callback function
71 *
72 * Note: passing null or undefined for 'object' makes the request fail in Opera 8.
73 *       Pass an empty string instead.
74 */
75function HTTPPost(uri, callbackFunction, callbackParameter, object) {
76  var xmlHttp = new XMLHttpRequest();
77  var bAsync = true;
78  if (!callbackFunction) {
79    bAsync = false;
80  }
81  xmlHttp.open('POST', uri, bAsync);
82
83  var toSend = '';
84  if (typeof object == 'object') {
85    xmlHttp.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
86    for (var i in object) {
87      toSend += (toSend ? '&' : '') + i + '=' + encodeURIComponent(object[i]);
88    }
89  }
90  else {
91    toSend = object;
92  }
93  xmlHttp.send(toSend);
94
95  if (bAsync) {
96    if (callbackFunction) {
97      xmlHttp.onreadystatechange = function() {
98        if (xmlHttp.readyState == 4) {
99          callbackFunction(xmlHttp.responseText, xmlHttp, callbackParameter);
100        }
101      }
102    }
103    return xmlHttp;
104  }
105  else {
106    return xmlHttp.responseText;
107  }
108}
109
110/**
111 * Redirects a button's form submission to a hidden iframe and displays the result
112 * in a given wrapper. The iframe should contain a call to
113 * window.parent.iframeHandler() after submission.
114 */
115function redirectFormButton(uri, button, handler) {
116  // (Re)create an iframe to target.
117  createIframe();
118
119  // Trap the button
120  button.onmouseover = button.onfocus = function() {
121    button.onclick = function() {
122      // Prepare variables for use in anonymous function.
123      var button = this;
124      var action = button.form.action;
125      var target = button.form.target;
126
127      // Redirect form submission
128      this.form.action = uri;
129      this.form.target = 'redirect-target';
130
131      handler.onsubmit();
132
133      // Set iframe handler for later
134      window.iframeHandler = function () {
135        var iframe = $('redirect-target');
136        // Restore form submission
137        button.form.action = action;
138        button.form.target = target;
139
140        // Get response from iframe body
141        try {
142          response = (iframe.contentWindow || iframe.contentDocument || iframe).document.body.innerHTML;
143          // Firefox 1.0.x hack: Remove (corrupted) control characters
144          response = response.replace(/[\f\n\r\t]/g, ' ');
145          if (window.opera) {
146            // Opera-hack: it returns innerHTML sanitized.
147            response = response.replace(/&quot;/g, '"');
148          }
149        }
150        catch (e) {
151          response = null;
152        }
153
154        $('redirect-target').onload = null;
155        $('redirect-target').src = 'about:blank';
156
157        response = parseJson(response);
158        // Check response code
159        if (response.status == 0) {
160          handler.onerror(response.data);
161          return;
162        }
163        handler.oncomplete(response.data);
164      }
165
166      return true;
167    }
168  }
169  button.onmouseout = button.onblur = function() {
170    button.onclick = null;
171  }
172}
173
174/**
175 * Adds a function to the window onload event
176 */
177function addLoadEvent(func) {
178  var oldOnload = window.onload;
179  if (typeof window.onload != 'function') {
180    window.onload = func;
181  }
182  else {
183    window.onload = function() {
184      oldOnload();
185      func();
186    }
187  }
188}
189
190/**
191 * Adds a function to a given form's submit event
192 */
193function addSubmitEvent(form, func) {
194  var oldSubmit = form.onsubmit;
195  if (typeof oldSubmit != 'function') {
196    form.onsubmit = func;
197  }
198  else {
199    form.onsubmit = function() {
200      return oldSubmit() && func();
201    }
202  }
203}
204
205/**
206 * Retrieves the absolute position of an element on the screen
207 */
208function absolutePosition(el) {
209  var sLeft = 0, sTop = 0;
210  var isDiv = /^div$/i.test(el.tagName);
211  if (isDiv && el.scrollLeft) {
212    sLeft = el.scrollLeft;
213  }
214  if (isDiv && el.scrollTop) {
215    sTop = el.scrollTop;
216  }
217  var r = { x: el.offsetLeft - sLeft, y: el.offsetTop - sTop };
218  if (el.offsetParent) {
219    var tmp = absolutePosition(el.offsetParent);
220    r.x += tmp.x;
221    r.y += tmp.y;
222  }
223  return r;
224};
225
226function dimensions(el) {
227  return { width: el.offsetWidth, height: el.offsetHeight };
228}
229
230/**
231 * Returns true if an element has a specified class name
232 */
233function hasClass(node, className) {
234  if (node.className == className) {
235    return true;
236  }
237  var reg = new RegExp('(^| )'+ className +'($| )')
238  if (reg.test(node.className)) {
239    return true;
240  }
241  return false;
242}
243
244/**
245 * Adds a class name to an element
246 */
247function addClass(node, className) {
248  if (hasClass(node, className)) {
249    return false;
250  }
251  node.className += ' '+ className;
252  return true;
253}
254
255/**
256 * Removes a class name from an element
257 */
258function removeClass(node, className) {
259  if (!hasClass(node, className)) {
260    return false;
261  }
262  // Replaces words surrounded with whitespace or at a string border with a space. Prevents multiple class names from being glued together.
263  node.className = eregReplace('(^|\\s+)'+ className +'($|\\s+)', ' ', node.className);
264  return true;
265}
266
267/**
268 * Toggles a class name on or off for an element
269 */
270function toggleClass(node, className) {
271  if (!removeClass(node, className) && !addClass(node, className)) {
272    return false;
273  }
274  return true;
275}
276
277/**
278 * Emulate PHP's ereg_replace function in javascript
279 */
280function eregReplace(search, replace, subject) {
281  return subject.replace(new RegExp(search,'g'), replace);
282}
283
284/**
285 * Removes an element from the page
286 */
287function removeNode(node) {
288  if (typeof node == 'string') {
289    node = $(node);
290  }
291  if (node && node.parentNode) {
292    return node.parentNode.removeChild(node);
293  }
294  else {
295    return false;
296  }
297}
298
299/**
300 * Prevents an event from propagating.
301 */
302function stopEvent(event) {
303  if (event.preventDefault) {
304    event.preventDefault();
305    event.stopPropagation();
306  }
307  else {
308    event.returnValue = false;
309    event.cancelBubble = true;
310  }
311}
312
313/**
314 * Parse a JSON response.
315 *
316 * The result is either the JSON object, or an object with 'status' 0 and 'data' an error message.
317 */
318function parseJson(data) {
319  if (data.substring(0,1) != '{') {
320    return { status: 0, data: data.length ? data : 'Unspecified error' };
321  }
322  return eval('(' + data + ');');
323}
324
325/**
326 * Create an invisible iframe for form submissions.
327 */
328function createIframe() {
329  // Delete any previous iframe
330  deleteIframe();
331  // Note: some browsers require the literal name/id attributes on the tag,
332  // some want them set through JS. We do both.
333  window.iframeHandler = function () {};
334  var div = document.createElement('div');
335  div.id = 'redirect-holder';
336  div.innerHTML = '<iframe name="redirect-target" id="redirect-target" class="redirect" onload="window.iframeHandler();"></iframe>';
337  var iframe = div.firstChild;
338  with (iframe) {
339    name = 'redirect-target';
340    setAttribute('name', 'redirect-target');
341    id = 'redirect-target';
342  }
343  with (iframe.style) {
344    position = 'absolute';
345    height = '1px';
346    width = '1px';
347    visibility = 'hidden';
348  }
349  document.body.appendChild(div);
350}
351
352/**
353 * Delete the invisible iframe for form submissions.
354 */
355function deleteIframe() {
356  var holder = $('redirect-holder');
357  if (holder != null) {
358    removeNode(holder);
359  }
360}
361
362/**
363 * Wrapper around document.getElementById().
364 */
365function $(id) {
366  return document.getElementById(id);
367}