instiki/vendor/rails/railties/html/javascripts/controls.js
Jacques Distler c358389f25 TeX and CSS tweaks.
Sync with latest Instiki Trunk
(Updates Rails to 1.2.2)
2007-02-09 02:04:31 -06:00

833 lines
28 KiB
JavaScript

// Copyright (c) 2005, 2006 Thomas Fuchs (http://script.aculo.us, http://mir.aculo.us)
// (c) 2005, 2006 Ivan Krstic (http://blogs.law.harvard.edu/ivan)
// (c) 2005, 2006 Jon Tirsen (http://www.tirsen.com)
// Contributors:
// Richard Livsey
// Rahul Bhargava
// Rob Wills
//
// script.aculo.us is freely distributable under the terms of an MIT-style license.
// For details, see the script.aculo.us web site: http://script.aculo.us/
// Autocompleter.Base handles all the autocompletion functionality
// that's independent of the data source for autocompletion. This
// includes drawing the autocompletion menu, observing keyboard
// and mouse events, and similar.
//
// Specific autocompleters need to provide, at the very least,
// a getUpdatedChoices function that will be invoked every time
// the text inside the monitored textbox changes. This method
// should get the text for which to provide autocompletion by
// invoking this.getToken(), NOT by directly accessing
// this.element.value. This is to allow incremental tokenized
// autocompletion. Specific auto-completion logic (AJAX, etc)
// belongs in getUpdatedChoices.
//
// Tokenized incremental autocompletion is enabled automatically
// when an autocompleter is instantiated with the 'tokens' option
// in the options parameter, e.g.:
// new Ajax.Autocompleter('id','upd', '/url/', { tokens: ',' });
// will incrementally autocomplete with a comma as the token.
// Additionally, ',' in the above example can be replaced with
// a token array, e.g. { tokens: [',', '\n'] } which
// enables autocompletion on multiple tokens. This is most
// useful when one of the tokens is \n (a newline), as it
// allows smart autocompletion after linebreaks.
if(typeof Effect == 'undefined')
throw("controls.js requires including script.aculo.us' effects.js library");
var Autocompleter = {}
Autocompleter.Base = function() {};
Autocompleter.Base.prototype = {
baseInitialize: function(element, update, options) {
this.element = $(element);
this.update = $(update);
this.hasFocus = false;
this.changed = false;
this.active = false;
this.index = 0;
this.entryCount = 0;
if(this.setOptions)
this.setOptions(options);
else
this.options = options || {};
this.options.paramName = this.options.paramName || this.element.name;
this.options.tokens = this.options.tokens || [];
this.options.frequency = this.options.frequency || 0.4;
this.options.minChars = this.options.minChars || 1;
this.options.onShow = this.options.onShow ||
function(element, update){
if(!update.style.position || update.style.position=='absolute') {
update.style.position = 'absolute';
Position.clone(element, update, {
setHeight: false,
offsetTop: element.offsetHeight
});
}
Effect.Appear(update,{duration:0.15});
};
this.options.onHide = this.options.onHide ||
function(element, update){ new Effect.Fade(update,{duration:0.15}) };
if(typeof(this.options.tokens) == 'string')
this.options.tokens = new Array(this.options.tokens);
this.observer = null;
this.element.setAttribute('autocomplete','off');
Element.hide(this.update);
Event.observe(this.element, "blur", this.onBlur.bindAsEventListener(this));
Event.observe(this.element, "keypress", this.onKeyPress.bindAsEventListener(this));
},
show: function() {
if(Element.getStyle(this.update, 'display')=='none') this.options.onShow(this.element, this.update);
if(!this.iefix &&
(navigator.appVersion.indexOf('MSIE')>0) &&
(navigator.userAgent.indexOf('Opera')<0) &&
(Element.getStyle(this.update, 'position')=='absolute')) {
new Insertion.After(this.update,
'<iframe id="' + this.update.id + '_iefix" '+
'style="display:none;position:absolute;filter:progid:DXImageTransform.Microsoft.Alpha(opacity=0);" ' +
'src="javascript:false;" frameborder="0" scrolling="no"></iframe>');
this.iefix = $(this.update.id+'_iefix');
}
if(this.iefix) setTimeout(this.fixIEOverlapping.bind(this), 50);
},
fixIEOverlapping: function() {
Position.clone(this.update, this.iefix, {setTop:(!this.update.style.height)});
this.iefix.style.zIndex = 1;
this.update.style.zIndex = 2;
Element.show(this.iefix);
},
hide: function() {
this.stopIndicator();
if(Element.getStyle(this.update, 'display')!='none') this.options.onHide(this.element, this.update);
if(this.iefix) Element.hide(this.iefix);
},
startIndicator: function() {
if(this.options.indicator) Element.show(this.options.indicator);
},
stopIndicator: function() {
if(this.options.indicator) Element.hide(this.options.indicator);
},
onKeyPress: function(event) {
if(this.active)
switch(event.keyCode) {
case Event.KEY_TAB:
case Event.KEY_RETURN:
this.selectEntry();
Event.stop(event);
case Event.KEY_ESC:
this.hide();
this.active = false;
Event.stop(event);
return;
case Event.KEY_LEFT:
case Event.KEY_RIGHT:
return;
case Event.KEY_UP:
this.markPrevious();
this.render();
if(navigator.appVersion.indexOf('AppleWebKit')>0) Event.stop(event);
return;
case Event.KEY_DOWN:
this.markNext();
this.render();
if(navigator.appVersion.indexOf('AppleWebKit')>0) Event.stop(event);
return;
}
else
if(event.keyCode==Event.KEY_TAB || event.keyCode==Event.KEY_RETURN ||
(navigator.appVersion.indexOf('AppleWebKit') > 0 && event.keyCode == 0)) return;
this.changed = true;
this.hasFocus = true;
if(this.observer) clearTimeout(this.observer);
this.observer =
setTimeout(this.onObserverEvent.bind(this), this.options.frequency*1000);
},
activate: function() {
this.changed = false;
this.hasFocus = true;
this.getUpdatedChoices();
},
onHover: function(event) {
var element = Event.findElement(event, 'LI');
if(this.index != element.autocompleteIndex)
{
this.index = element.autocompleteIndex;
this.render();
}
Event.stop(event);
},
onClick: function(event) {
var element = Event.findElement(event, 'LI');
this.index = element.autocompleteIndex;
this.selectEntry();
this.hide();
},
onBlur: function(event) {
// needed to make click events working
setTimeout(this.hide.bind(this), 250);
this.hasFocus = false;
this.active = false;
},
render: function() {
if(this.entryCount > 0) {
for (var i = 0; i < this.entryCount; i++)
this.index==i ?
Element.addClassName(this.getEntry(i),"selected") :
Element.removeClassName(this.getEntry(i),"selected");
if(this.hasFocus) {
this.show();
this.active = true;
}
} else {
this.active = false;
this.hide();
}
},
markPrevious: function() {
if(this.index > 0) this.index--
else this.index = this.entryCount-1;
this.getEntry(this.index).scrollIntoView(true);
},
markNext: function() {
if(this.index < this.entryCount-1) this.index++
else this.index = 0;
this.getEntry(this.index).scrollIntoView(false);
},
getEntry: function(index) {
return this.update.firstChild.childNodes[index];
},
getCurrentEntry: function() {
return this.getEntry(this.index);
},
selectEntry: function() {
this.active = false;
this.updateElement(this.getCurrentEntry());
},
updateElement: function(selectedElement) {
if (this.options.updateElement) {
this.options.updateElement(selectedElement);
return;
}
var value = '';
if (this.options.select) {
var nodes = document.getElementsByClassName(this.options.select, selectedElement) || [];
if(nodes.length>0) value = Element.collectTextNodes(nodes[0], this.options.select);
} else
value = Element.collectTextNodesIgnoreClass(selectedElement, 'informal');
var lastTokenPos = this.findLastToken();
if (lastTokenPos != -1) {
var newValue = this.element.value.substr(0, lastTokenPos + 1);
var whitespace = this.element.value.substr(lastTokenPos + 1).match(/^\s+/);
if (whitespace)
newValue += whitespace[0];
this.element.value = newValue + value;
} else {
this.element.value = value;
}
this.element.focus();
if (this.options.afterUpdateElement)
this.options.afterUpdateElement(this.element, selectedElement);
},
updateChoices: function(choices) {
if(!this.changed && this.hasFocus) {
this.update.innerHTML = choices;
Element.cleanWhitespace(this.update);
Element.cleanWhitespace(this.update.down());
if(this.update.firstChild && this.update.down().childNodes) {
this.entryCount =
this.update.down().childNodes.length;
for (var i = 0; i < this.entryCount; i++) {
var entry = this.getEntry(i);
entry.autocompleteIndex = i;
this.addObservers(entry);
}
} else {
this.entryCount = 0;
}
this.stopIndicator();
this.index = 0;
if(this.entryCount==1 && this.options.autoSelect) {
this.selectEntry();
this.hide();
} else {
this.render();
}
}
},
addObservers: function(element) {
Event.observe(element, "mouseover", this.onHover.bindAsEventListener(this));
Event.observe(element, "click", this.onClick.bindAsEventListener(this));
},
onObserverEvent: function() {
this.changed = false;
if(this.getToken().length>=this.options.minChars) {
this.startIndicator();
this.getUpdatedChoices();
} else {
this.active = false;
this.hide();
}
},
getToken: function() {
var tokenPos = this.findLastToken();
if (tokenPos != -1)
var ret = this.element.value.substr(tokenPos + 1).replace(/^\s+/,'').replace(/\s+$/,'');
else
var ret = this.element.value;
return /\n/.test(ret) ? '' : ret;
},
findLastToken: function() {
var lastTokenPos = -1;
for (var i=0; i<this.options.tokens.length; i++) {
var thisTokenPos = this.element.value.lastIndexOf(this.options.tokens[i]);
if (thisTokenPos > lastTokenPos)
lastTokenPos = thisTokenPos;
}
return lastTokenPos;
}
}
Ajax.Autocompleter = Class.create();
Object.extend(Object.extend(Ajax.Autocompleter.prototype, Autocompleter.Base.prototype), {
initialize: function(element, update, url, options) {
this.baseInitialize(element, update, options);
this.options.asynchronous = true;
this.options.onComplete = this.onComplete.bind(this);
this.options.defaultParams = this.options.parameters || null;
this.url = url;
},
getUpdatedChoices: function() {
entry = encodeURIComponent(this.options.paramName) + '=' +
encodeURIComponent(this.getToken());
this.options.parameters = this.options.callback ?
this.options.callback(this.element, entry) : entry;
if(this.options.defaultParams)
this.options.parameters += '&' + this.options.defaultParams;
new Ajax.Request(this.url, this.options);
},
onComplete: function(request) {
this.updateChoices(request.responseText);
}
});
// The local array autocompleter. Used when you'd prefer to
// inject an array of autocompletion options into the page, rather
// than sending out Ajax queries, which can be quite slow sometimes.
//
// The constructor takes four parameters. The first two are, as usual,
// the id of the monitored textbox, and id of the autocompletion menu.
// The third is the array you want to autocomplete from, and the fourth
// is the options block.
//
// Extra local autocompletion options:
// - choices - How many autocompletion choices to offer
//
// - partialSearch - If false, the autocompleter will match entered
// text only at the beginning of strings in the
// autocomplete array. Defaults to true, which will
// match text at the beginning of any *word* in the
// strings in the autocomplete array. If you want to
// search anywhere in the string, additionally set
// the option fullSearch to true (default: off).
//
// - fullSsearch - Search anywhere in autocomplete array strings.
//
// - partialChars - How many characters to enter before triggering
// a partial match (unlike minChars, which defines
// how many characters are required to do any match
// at all). Defaults to 2.
//
// - ignoreCase - Whether to ignore case when autocompleting.
// Defaults to true.
//
// It's possible to pass in a custom function as the 'selector'
// option, if you prefer to write your own autocompletion logic.
// In that case, the other options above will not apply unless
// you support them.
Autocompleter.Local = Class.create();
Autocompleter.Local.prototype = Object.extend(new Autocompleter.Base(), {
initialize: function(element, update, array, options) {
this.baseInitialize(element, update, options);
this.options.array = array;
},
getUpdatedChoices: function() {
this.updateChoices(this.options.selector(this));
},
setOptions: function(options) {
this.options = Object.extend({
choices: 10,
partialSearch: true,
partialChars: 2,
ignoreCase: true,
fullSearch: false,
selector: function(instance) {
var ret = []; // Beginning matches
var partial = []; // Inside matches
var entry = instance.getToken();
var count = 0;
for (var i = 0; i < instance.options.array.length &&
ret.length < instance.options.choices ; i++) {
var elem = instance.options.array[i];
var foundPos = instance.options.ignoreCase ?
elem.toLowerCase().indexOf(entry.toLowerCase()) :
elem.indexOf(entry);
while (foundPos != -1) {
if (foundPos == 0 && elem.length != entry.length) {
ret.push("<li><strong>" + elem.substr(0, entry.length) + "</strong>" +
elem.substr(entry.length) + "</li>");
break;
} else if (entry.length >= instance.options.partialChars &&
instance.options.partialSearch && foundPos != -1) {
if (instance.options.fullSearch || /\s/.test(elem.substr(foundPos-1,1))) {
partial.push("<li>" + elem.substr(0, foundPos) + "<strong>" +
elem.substr(foundPos, entry.length) + "</strong>" + elem.substr(
foundPos + entry.length) + "</li>");
break;
}
}
foundPos = instance.options.ignoreCase ?
elem.toLowerCase().indexOf(entry.toLowerCase(), foundPos + 1) :
elem.indexOf(entry, foundPos + 1);
}
}
if (partial.length)
ret = ret.concat(partial.slice(0, instance.options.choices - ret.length))
return "<ul>" + ret.join('') + "</ul>";
}
}, options || {});
}
});
// AJAX in-place editor
//
// see documentation on http://wiki.script.aculo.us/scriptaculous/show/Ajax.InPlaceEditor
// Use this if you notice weird scrolling problems on some browsers,
// the DOM might be a bit confused when this gets called so do this
// waits 1 ms (with setTimeout) until it does the activation
Field.scrollFreeActivate = function(field) {
setTimeout(function() {
Field.activate(field);
}, 1);
}
Ajax.InPlaceEditor = Class.create();
Ajax.InPlaceEditor.defaultHighlightColor = "#FFFF99";
Ajax.InPlaceEditor.prototype = {
initialize: function(element, url, options) {
this.url = url;
this.element = $(element);
this.options = Object.extend({
paramName: "value",
okButton: true,
okText: "ok",
cancelLink: true,
cancelText: "cancel",
savingText: "Saving...",
clickToEditText: "Click to edit",
okText: "ok",
rows: 1,
onComplete: function(transport, element) {
new Effect.Highlight(element, {startcolor: this.options.highlightcolor});
},
onFailure: function(transport) {
alert("Error communicating with the server: " + transport.responseText.stripTags());
},
callback: function(form) {
return Form.serialize(form);
},
handleLineBreaks: true,
loadingText: 'Loading...',
savingClassName: 'inplaceeditor-saving',
loadingClassName: 'inplaceeditor-loading',
formClassName: 'inplaceeditor-form',
highlightcolor: Ajax.InPlaceEditor.defaultHighlightColor,
highlightendcolor: "#FFFFFF",
externalControl: null,
submitOnBlur: false,
ajaxOptions: {},
evalScripts: false
}, options || {});
if(!this.options.formId && this.element.id) {
this.options.formId = this.element.id + "-inplaceeditor";
if ($(this.options.formId)) {
// there's already a form with that name, don't specify an id
this.options.formId = null;
}
}
if (this.options.externalControl) {
this.options.externalControl = $(this.options.externalControl);
}
this.originalBackground = Element.getStyle(this.element, 'background-color');
if (!this.originalBackground) {
this.originalBackground = "transparent";
}
this.element.title = this.options.clickToEditText;
this.onclickListener = this.enterEditMode.bindAsEventListener(this);
this.mouseoverListener = this.enterHover.bindAsEventListener(this);
this.mouseoutListener = this.leaveHover.bindAsEventListener(this);
Event.observe(this.element, 'click', this.onclickListener);
Event.observe(this.element, 'mouseover', this.mouseoverListener);
Event.observe(this.element, 'mouseout', this.mouseoutListener);
if (this.options.externalControl) {
Event.observe(this.options.externalControl, 'click', this.onclickListener);
Event.observe(this.options.externalControl, 'mouseover', this.mouseoverListener);
Event.observe(this.options.externalControl, 'mouseout', this.mouseoutListener);
}
},
enterEditMode: function(evt) {
if (this.saving) return;
if (this.editing) return;
this.editing = true;
this.onEnterEditMode();
if (this.options.externalControl) {
Element.hide(this.options.externalControl);
}
Element.hide(this.element);
this.createForm();
this.element.parentNode.insertBefore(this.form, this.element);
if (!this.options.loadTextURL) Field.scrollFreeActivate(this.editField);
// stop the event to avoid a page refresh in Safari
if (evt) {
Event.stop(evt);
}
return false;
},
createForm: function() {
this.form = document.createElement("form");
this.form.id = this.options.formId;
Element.addClassName(this.form, this.options.formClassName)
this.form.onsubmit = this.onSubmit.bind(this);
this.createEditField();
if (this.options.textarea) {
var br = document.createElement("br");
this.form.appendChild(br);
}
if (this.options.okButton) {
okButton = document.createElement("input");
okButton.type = "submit";
okButton.value = this.options.okText;
okButton.className = 'editor_ok_button';
this.form.appendChild(okButton);
}
if (this.options.cancelLink) {
cancelLink = document.createElement("a");
cancelLink.href = "#";
cancelLink.appendChild(document.createTextNode(this.options.cancelText));
cancelLink.onclick = this.onclickCancel.bind(this);
cancelLink.className = 'editor_cancel';
this.form.appendChild(cancelLink);
}
},
hasHTMLLineBreaks: function(string) {
if (!this.options.handleLineBreaks) return false;
return string.match(/<br/i) || string.match(/<p>/i);
},
convertHTMLLineBreaks: function(string) {
return string.replace(/<br>/gi, "\n").replace(/<br\/>/gi, "\n").replace(/<\/p>/gi, "\n").replace(/<p>/gi, "");
},
createEditField: function() {
var text;
if(this.options.loadTextURL) {
text = this.options.loadingText;
} else {
text = this.getText();
}
var obj = this;
if (this.options.rows == 1 && !this.hasHTMLLineBreaks(text)) {
this.options.textarea = false;
var textField = document.createElement("input");
textField.obj = this;
textField.type = "text";
textField.name = this.options.paramName;
textField.value = text;
textField.style.backgroundColor = this.options.highlightcolor;
textField.className = 'editor_field';
var size = this.options.size || this.options.cols || 0;
if (size != 0) textField.size = size;
if (this.options.submitOnBlur)
textField.onblur = this.onSubmit.bind(this);
this.editField = textField;
} else {
this.options.textarea = true;
var textArea = document.createElement("textarea");
textArea.obj = this;
textArea.name = this.options.paramName;
textArea.value = this.convertHTMLLineBreaks(text);
textArea.rows = this.options.rows;
textArea.cols = this.options.cols || 40;
textArea.className = 'editor_field';
if (this.options.submitOnBlur)
textArea.onblur = this.onSubmit.bind(this);
this.editField = textArea;
}
if(this.options.loadTextURL) {
this.loadExternalText();
}
this.form.appendChild(this.editField);
},
getText: function() {
return this.element.innerHTML;
},
loadExternalText: function() {
Element.addClassName(this.form, this.options.loadingClassName);
this.editField.disabled = true;
new Ajax.Request(
this.options.loadTextURL,
Object.extend({
asynchronous: true,
onComplete: this.onLoadedExternalText.bind(this)
}, this.options.ajaxOptions)
);
},
onLoadedExternalText: function(transport) {
Element.removeClassName(this.form, this.options.loadingClassName);
this.editField.disabled = false;
this.editField.value = transport.responseText.stripTags();
Field.scrollFreeActivate(this.editField);
},
onclickCancel: function() {
this.onComplete();
this.leaveEditMode();
return false;
},
onFailure: function(transport) {
this.options.onFailure(transport);
if (this.oldInnerHTML) {
this.element.innerHTML = this.oldInnerHTML;
this.oldInnerHTML = null;
}
return false;
},
onSubmit: function() {
// onLoading resets these so we need to save them away for the Ajax call
var form = this.form;
var value = this.editField.value;
// do this first, sometimes the ajax call returns before we get a chance to switch on Saving...
// which means this will actually switch on Saving... *after* we've left edit mode causing Saving...
// to be displayed indefinitely
this.onLoading();
if (this.options.evalScripts) {
new Ajax.Request(
this.url, Object.extend({
parameters: this.options.callback(form, value),
onComplete: this.onComplete.bind(this),
onFailure: this.onFailure.bind(this),
asynchronous:true,
evalScripts:true
}, this.options.ajaxOptions));
} else {
new Ajax.Updater(
{ success: this.element,
// don't update on failure (this could be an option)
failure: null },
this.url, Object.extend({
parameters: this.options.callback(form, value),
onComplete: this.onComplete.bind(this),
onFailure: this.onFailure.bind(this)
}, this.options.ajaxOptions));
}
// stop the event to avoid a page refresh in Safari
if (arguments.length > 1) {
Event.stop(arguments[0]);
}
return false;
},
onLoading: function() {
this.saving = true;
this.removeForm();
this.leaveHover();
this.showSaving();
},
showSaving: function() {
this.oldInnerHTML = this.element.innerHTML;
this.element.innerHTML = this.options.savingText;
Element.addClassName(this.element, this.options.savingClassName);
this.element.style.backgroundColor = this.originalBackground;
Element.show(this.element);
},
removeForm: function() {
if(this.form) {
if (this.form.parentNode) Element.remove(this.form);
this.form = null;
}
},
enterHover: function() {
if (this.saving) return;
this.element.style.backgroundColor = this.options.highlightcolor;
if (this.effect) {
this.effect.cancel();
}
Element.addClassName(this.element, this.options.hoverClassName)
},
leaveHover: function() {
if (this.options.backgroundColor) {
this.element.style.backgroundColor = this.oldBackground;
}
Element.removeClassName(this.element, this.options.hoverClassName)
if (this.saving) return;
this.effect = new Effect.Highlight(this.element, {
startcolor: this.options.highlightcolor,
endcolor: this.options.highlightendcolor,
restorecolor: this.originalBackground
});
},
leaveEditMode: function() {
Element.removeClassName(this.element, this.options.savingClassName);
this.removeForm();
this.leaveHover();
this.element.style.backgroundColor = this.originalBackground;
Element.show(this.element);
if (this.options.externalControl) {
Element.show(this.options.externalControl);
}
this.editing = false;
this.saving = false;
this.oldInnerHTML = null;
this.onLeaveEditMode();
},
onComplete: function(transport) {
this.leaveEditMode();
this.options.onComplete.bind(this)(transport, this.element);
},
onEnterEditMode: function() {},
onLeaveEditMode: function() {},
dispose: function() {
if (this.oldInnerHTML) {
this.element.innerHTML = this.oldInnerHTML;
}
this.leaveEditMode();
Event.stopObserving(this.element, 'click', this.onclickListener);
Event.stopObserving(this.element, 'mouseover', this.mouseoverListener);
Event.stopObserving(this.element, 'mouseout', this.mouseoutListener);
if (this.options.externalControl) {
Event.stopObserving(this.options.externalControl, 'click', this.onclickListener);
Event.stopObserving(this.options.externalControl, 'mouseover', this.mouseoverListener);
Event.stopObserving(this.options.externalControl, 'mouseout', this.mouseoutListener);
}
}
};
Ajax.InPlaceCollectionEditor = Class.create();
Object.extend(Ajax.InPlaceCollectionEditor.prototype, Ajax.InPlaceEditor.prototype);
Object.extend(Ajax.InPlaceCollectionEditor.prototype, {
createEditField: function() {
if (!this.cached_selectTag) {
var selectTag = document.createElement("select");
var collection = this.options.collection || [];
var optionTag;
collection.each(function(e,i) {
optionTag = document.createElement("option");
optionTag.value = (e instanceof Array) ? e[0] : e;
if((typeof this.options.value == 'undefined') &&
((e instanceof Array) ? this.element.innerHTML == e[1] : e == optionTag.value)) optionTag.selected = true;
if(this.options.value==optionTag.value) optionTag.selected = true;
optionTag.appendChild(document.createTextNode((e instanceof Array) ? e[1] : e));
selectTag.appendChild(optionTag);
}.bind(this));
this.cached_selectTag = selectTag;
}
this.editField = this.cached_selectTag;
if(this.options.loadTextURL) this.loadExternalText();
this.form.appendChild(this.editField);
this.options.callback = function(form, value) {
return "value=" + encodeURIComponent(value);
}
}
});
// Delayed observer, like Form.Element.Observer,
// but waits for delay after last key input
// Ideal for live-search fields
Form.Element.DelayedObserver = Class.create();
Form.Element.DelayedObserver.prototype = {
initialize: function(element, delay, callback) {
this.delay = delay || 0.5;
this.element = $(element);
this.callback = callback;
this.timer = null;
this.lastValue = $F(this.element);
Event.observe(this.element,'keyup',this.delayedListener.bindAsEventListener(this));
},
delayedListener: function(event) {
if(this.lastValue == $F(this.element)) return;
if(this.timer) clearTimeout(this.timer);
this.timer = setTimeout(this.onTimerEvent.bind(this), this.delay * 1000);
this.lastValue = $F(this.element);
},
onTimerEvent: function() {
this.timer = null;
this.callback(this.element, $F(this.element));
}
};