jQuery bind event listener before another
Using the prettyPhoto plugin to open modal-style content containers, and trying to integrate with Google Analytics' Event Tracking to track when videos get opened.
Trouble is, when I
$('a.videoClickListener').click(function(event){
console.log('here');
_gaq.push(['_trackEvent', 'Product Page', 'Video Open', '<?php echo $product->getNameWithManufacturer(); ?>']);
});
the event is never fired, as prettyPhoto stops the event from continuing (quite rightly, as otherwise the page would change if a hyperlink was clicked).
prettyPhoto does not seem to provide an 'open' callback function, but if it did I couldn't use it anyway, as the prettyPhoto listeners are set up somewhere in the layout (we use rel=开发者_JAVA百科"prettyPhoto"
every time we want to use prettyPhoto, and pass params through the URL, which is the prettyPhoto-recommended way of doing things). I would also like to pass the product details to Analytics, ruling out a global video-opening listener across all prettyPhoto opening events.
How can I bind my listener before the prettyPhoto listener? If it turns out I have to use .unbind()
, then bind my listener, and then rebind prettyPhoto, how can I unbind a handler specified in a plugin?
Ideally, you would be able to add your event binding before any others, so that it executes first.
Unfortunately, jQuery doesn't seem to include any such facility.
However, I've coded a preBind method, which seems to do the trick:
$.fn.preBind = function(type, data, fn) {
this.bind(type, data, fn);
var currentBindings = this.data('events')[type];
var currentBindingsLastIndex = currentBindings.length - 1;
var newBindings = [];
newBindings.push(currentBindings[currentBindingsLastIndex]);
$.each(currentBindings, function (index) {
if (index < currentBindingsLastIndex)
newBindings.push(this);
});
this.data('events')[type] = newBindings;
return this;
};
Usage:
$('#button').bind('click', function() {
console.log('world');
});
// 2nd apostrophe for the selector was missing
$('#button').preBind('click', function() {
console.log('hello');
});
$('#button').click();
// Output:
//
// > "hello"
// > "world"
I'm using Jonathan's preBind method, slightly modified, and it does the trick nicely.
$.fn.preBind = function (type, data, fn) {
this.each(function () {
var $this = $(this);
$this.bind(type, data, fn);
var currentBindings = $this.data('events')[type];
if ($.isArray(currentBindings)) {
currentBindings.unshift(currentBindings.pop());
}
});
return this;
};
Worked for me with older and newer jQuery
versions:
/**
* @link http://stackoverflow.com/a/26892146/655224
*/
jQuery.fn.getEvents = function() {
if (typeof(jQuery._data) == 'function') {
return jQuery._data(this.get(0), 'events') || {};
} else if (typeof(this.data) == 'function') { // jQuery version < 1.7.?
return this.data('events') || {};
}
return {};
};
jQuery.fn.preBind = function(type, data, fn) {
this.each(function () {
var $this = jQuery(this);
$this.bind(type, data, fn);
var currentBindings = $this.getEvents()[type];
if (jQuery.isArray(currentBindings)) {
currentBindings.unshift(currentBindings.pop());
}
});
return this;
};
But beware, this functions can only return/prebind that events that was set with jQuery itself.
Special thanks to @jonathanconway and @Patrick...
Here is a variant of the solution using the more modern .On() approach.
// Same as .on() but moves the binding to the front of the queue.
$.fn.priorityOn = function (type, selector, data, fn) {
this.each(function () {
var $this = $(this);
var types = type.split(" ");
for (var t in types) {
$this.on(types[t], selector, data, fn);
var currentBindings = $._data(this, 'events')[types[t]];
if ($.isArray(currentBindings)) {
currentBindings.unshift(currentBindings.pop());
}
}
});
return this;
};
Usage is like
$(document).priorityOn("click blur change", ".some .selector input", function (e) {
// Your code.
});
Here is a slightly modified version of braks answer that also supports namespaces and type as plain object:
$.fn.prioOn = function(type, selector, data, fn, /*INTERNAL*/ one) {
// Types can be a map of types/handlers
if (typeof types === 'object') {
// ( types-Object, selector, data )
if (typeof selector !== 'string') {
// ( types-Object, data )
data = data || selector;
selector = undefined;
}
for (type in types) {
if (!types.hasOwnProperty(type)) continue;
this.prioOn(type, selector, data, types[type], one);
}
return this;
}
this.each(function() {
var $this = $(this);
var types = type.split(' ');
for (var t in types) {
if (!types.hasOwnProperty(t)) continue;
$this.on(types[t], selector, data, fn, one);
var currentBindings = $._data(this, 'events')[types[t].split('.')[0]];
if ($.isArray(currentBindings)) {
currentBindings.unshift(currentBindings.pop());
}
}
});
return this;
};
Had to change one line in the above code to make it work:
var currentBindings = $this.data('events',type); // var currentBindings = $this.data('events')[type];
This could be because I am using jquery 2.0.3
if you use unbind() then even the bindings made by plugins will be unbinded.
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