impressionist/test_app/public/javascripts/rails.js

176 lines
5.7 KiB
JavaScript

(function() {
// Technique from Juriy Zaytsev
// http://thinkweb2.com/projects/prototype/detecting-event-support-without-browser-sniffing/
function isEventSupported(eventName) {
var el = document.createElement('div');
eventName = 'on' + eventName;
var isSupported = (eventName in el);
if (!isSupported) {
el.setAttribute(eventName, 'return;');
isSupported = typeof el[eventName] == 'function';
}
el = null;
return isSupported;
}
function isForm(element) {
return Object.isElement(element) && element.nodeName.toUpperCase() == 'FORM'
}
function isInput(element) {
if (Object.isElement(element)) {
var name = element.nodeName.toUpperCase()
return name == 'INPUT' || name == 'SELECT' || name == 'TEXTAREA'
}
else return false
}
var submitBubbles = isEventSupported('submit'),
changeBubbles = isEventSupported('change')
if (!submitBubbles || !changeBubbles) {
// augment the Event.Handler class to observe custom events when needed
Event.Handler.prototype.initialize = Event.Handler.prototype.initialize.wrap(
function(init, element, eventName, selector, callback) {
init(element, eventName, selector, callback)
// is the handler being attached to an element that doesn't support this event?
if ( (!submitBubbles && this.eventName == 'submit' && !isForm(this.element)) ||
(!changeBubbles && this.eventName == 'change' && !isInput(this.element)) ) {
// "submit" => "emulated:submit"
this.eventName = 'emulated:' + this.eventName
}
}
)
}
if (!submitBubbles) {
// discover forms on the page by observing focus events which always bubble
document.on('focusin', 'form', function(focusEvent, form) {
// special handler for the real "submit" event (one-time operation)
if (!form.retrieve('emulated:submit')) {
form.on('submit', function(submitEvent) {
var emulated = form.fire('emulated:submit', submitEvent, true)
// if custom event received preventDefault, cancel the real one too
if (emulated.returnValue === false) submitEvent.preventDefault()
})
form.store('emulated:submit', true)
}
})
}
if (!changeBubbles) {
// discover form inputs on the page
document.on('focusin', 'input, select, texarea', function(focusEvent, input) {
// special handler for real "change" events
if (!input.retrieve('emulated:change')) {
input.on('change', function(changeEvent) {
input.fire('emulated:change', changeEvent, true)
})
input.store('emulated:change', true)
}
})
}
function handleRemote(element) {
var method, url, params;
var event = element.fire("ajax:before");
if (event.stopped) return false;
if (element.tagName.toLowerCase() === 'form') {
method = element.readAttribute('method') || 'post';
url = element.readAttribute('action');
params = element.serialize();
} else {
method = element.readAttribute('data-method') || 'get';
url = element.readAttribute('href');
params = {};
}
new Ajax.Request(url, {
method: method,
parameters: params,
evalScripts: true,
onComplete: function(request) { element.fire("ajax:complete", request); },
onSuccess: function(request) { element.fire("ajax:success", request); },
onFailure: function(request) { element.fire("ajax:failure", request); }
});
element.fire("ajax:after");
}
function handleMethod(element) {
var method = element.readAttribute('data-method'),
url = element.readAttribute('href'),
csrf_param = $$('meta[name=csrf-param]')[0],
csrf_token = $$('meta[name=csrf-token]')[0];
var form = new Element('form', { method: "POST", action: url, style: "display: none;" });
element.parentNode.insert(form);
if (method !== 'post') {
var field = new Element('input', { type: 'hidden', name: '_method', value: method });
form.insert(field);
}
if (csrf_param) {
var param = csrf_param.readAttribute('content'),
token = csrf_token.readAttribute('content'),
field = new Element('input', { type: 'hidden', name: param, value: token });
form.insert(field);
}
form.submit();
}
document.on("click", "*[data-confirm]", function(event, element) {
var message = element.readAttribute('data-confirm');
if (!confirm(message)) event.stop();
});
document.on("click", "a[data-remote]", function(event, element) {
if (event.stopped) return;
handleRemote(element);
event.stop();
});
document.on("click", "a[data-method]", function(event, element) {
if (event.stopped) return;
handleMethod(element);
event.stop();
});
document.on("submit", function(event) {
var element = event.findElement(),
message = element.readAttribute('data-confirm');
if (message && !confirm(message)) {
event.stop();
return false;
}
var inputs = element.select("input[type=submit][data-disable-with]");
inputs.each(function(input) {
input.disabled = true;
input.writeAttribute('data-original-value', input.value);
input.value = input.readAttribute('data-disable-with');
});
var element = event.findElement("form[data-remote]");
if (element) {
handleRemote(element);
event.stop();
}
});
document.on("ajax:after", "form", function(event, element) {
var inputs = element.select("input[type=submit][disabled=true][data-disable-with]");
inputs.each(function(input) {
input.value = input.readAttribute('data-original-value');
input.removeAttribute('data-original-value');
input.disabled = false;
});
});
})();