The plugin has this variable
this.onValid = options.onValid || function(){ this.insertMessage(this.createMessageSpan()); this.addFieldClass(); };
The problem is,when i define a new instance I want to add a new function to this.onValid, I don't want to override the default events?
How can I extend the variable this.onValid ?
this.onValid = options.onValid || function(){ this.insertMessage(this.createMessageSpan()); this.addFieldClass(); };
//That above is already defined;
this._onValid = this.onValid; //Make a backup function
this.onValid = function (){
this._onValid(); //Call the actual function
//Your extended code here //Call your code
}
That was specific to your code. To understand it better, maybe this example will help:
writeA = function (){
document.write('a');
};
//Now I want to extend the writeA function to write 'b' as well
_writeA = writeA;
writeA = function (){
_writeA(); //So now I call whatever the function originally did
document.write('b'); //And now I execute what I want to add to the function
};
Example's demo
Just tried fixing the code you provided in the comment. Try this:
var obj1 = {
this._onValid = this.onValid; //Do this assuming this.onValid is already defined
onValid: function(){ //Redefine it
this._onValid();
newFunction();
}
};
Edit
From the plugin. Just edit it to look like this:
this.onValid = options.onValid || function(){ this.insertMessage(this.createMessageSpan()); this.addFieldClass(); };
this._onValid = this.onValid;
this.onValid = function (){
this._onValid();
//YOUR CODE HERE
};
I have edited the original file to look like that here.
Hah, just realized I put the same code as I had in the beginning here. Well, that's because that's exactly how it should look. See my edited file and search for //YOUR CODE HERE and add your code there.
Related
I create a simple jQuery extension(it's my first).
(function($){
var MyClass = function(opt){
//..
};
//one of the methods of my extension
$.fn.myExtension = function(opt){
this._ext = new MyClass(opt);
return this;
};
$.fn.myExtensionOtherMethod = function(){
if(this._ext){
//do something ..
}
return this;
};
}(jQuery));
//using ..
$(document).ready(function(){
$('#selector').myExtension({
//options ..
});
$('#selector').myExtensionOtherMethod();
});
when i invoke method $('#selector').myExtensionOtherMethod();, this does not contains this._ext variable. I know that this is other scope, but i know that there is some way to access that variable in both methods.how can i do it?
This isn't really a scope issue. This is because the jQuery prototype $.fn gives you a jquery object as this. Even though you are selecting the same element each time its a new jQuery object set as the context so that property is gone. You can put that property on the DOM element and achieve the outcome you want.
(function($) {
var MyClass = function(opt) {};
//one of the methods of my extension
$.fn.myExtension = function(opt) {
this[0]._ext = new MyClass(opt);
return this;
};
$.fn.myExtensionOtherMethod = function() {
if (this[0]._ext) {
//do something ..
}
return this;
};
}(jQuery));
//using ..
$(document).ready(function() {
$('#selector').myExtension({
//options ..
});
$('#selector').myExtensionOtherMethod();
});
This is just a quick example above. If your selector finds more than one element you should loop though them. But I only grabbed the first index since you were selecting by ID.
Fiddle: https://jsfiddle.net/AtheistP3ace/gd1ehk0d/
As mentioned above by #charlietfl, I agree with that comment. Happy to explain why what you did didn't work but there may be better ways to achieve what you are looking for.
var fbToggle = document.getElementById("fbToggle");
and later in the script
fbToggle.addEventListener("click", toggle("fbContainer"));
Console tells me that fbToggle is NULL
This is in the document though.
<input type="checkbox" id="fbToggle">
I wasnt using eventListener before, so maybe there is a special order of declaration i'm missing ?
EDIT :
entire js :
function toggle(target) {
var obj = document.getElementById(target);
display = obj.style.display;
if (display == "none") {display = "block"}
else {display = "none"}
}
function init() {
var fbToggle = document.getElementById("fbToggle");
var twitToggle = document.getElementById("twitToggle");
var pinToggle = document.getElementById("pinToggle");
console.log(fbToggle); // NULL
fbToggle.addEventListener("click", toggle("fbContainer"));
twitToggle.addEventListener("click", toggle("twitContainer"));
pinToggle.addEventListener("click", toggle("pinContainer"));
}
window.onload = init();
HTML is way too long.but JS is in head, called from external file. Also i'm not in quirk mode.
It is not clear where "later in the script" is. If it is in different scope definitely it is not going to work. Suggesting you to keep everything in a global object if possible so that you can access from different places in the script.
window.globals = {};
window.globals.fbToggle = document.getElementById("fbToggle");
window.globals.fbToggle.addEventListener("click", function () {
toggle("fbContainer")
});
function toggle(container) {
alert(container);
}
http://jsfiddle.net/ST938/
Another point is addEventListener expects a function or function idenitifier, NOT a function call.
addEventListener("click", toggle("fbContainer")); // wrong
addEventListener("click", toggle); // correct
So if you want to pass a parameter
window.globals.fbToggle.addEventListener("click", function () {
toggle("fbContainer")
});
function toggle(container) {
alert(container);
}
In JavaScript, putting brackets after a function name causes it to be called. If you want to reference a function without calling it you must not put brackets after the name:
window.onload = init(); // this calls init() immediately
window.onload = init; // this correctly stores init in window.onload
The same applies to toggle(). If you need to pre-specify some of the arguments you can wrap it in an anonymous function:
fbToggle.addEventListener("click", function() { toggle("fbContainer"); });
or you can use bind:
fbToggle.addEventListener("click", toggle.bind(null, "fbContainer"));
I'm using reuqireJS and am struggling to call a function, which is in a js file I'm requiring. My main app.js "controller" requires (plugin)app.js, which handles all plugin configuration and plugin related functions.
This is from app.js
define([], function(){
var start = function() {
require(['jquery', 'overrides', 'jqm', 'multiview', 'respond'],function() {
// globals
var
// PROBLEM attempt at an external plugin function object
dataTablesExt = {},
...;
// call for (plugin)app.js
enhanceDataTables =
function( page, from ) {
var datatable = page.find('.table-wrapper table');
if ( datatable.length > 0 && datatable.jqmData('bound') != true ) {
datatable.not(':jqmData(bound="true")')
.each( function() {
var that = $(this),
tblstyle = that.jqmData("table-style");
that.jqmData('bound', true);
require(['services/datatables/app'], function (App) {
// this calls (plugin)app.js
App.render({style: tblstyle, table: that });
});
});
}
};
// PROBLEM - try to call function "Hello" inside datatables.app
anotherFunc=
function( page, from ) {
dataTablesExt.sayHello("john");
};
I guess my problem is how to set up the global variable dataTablesExt, so I can "fill" it with functions to be called globally. Here is what I'm trying inside (plugin)app.js:
define(['services/datatables/app', 'services/datatables/datatables.min'], function( app, datatables ) {
function render(parameters) {
...
// the function I want to call
function helloName( name ){
alert( name );
};
// I'm trying to add this function to the global "dataTablesExt"
dataTablesExt.sayHello = helloName;
}
But... doesn't work. I'm always getting:
dataTablesExt.sayHello is not a function
Question:
Can someone point me to what I'm doing wrong? If this is not possible, what would be an alternative.
I was thinking to trigger a custom event, but I would have to set up an object to pass along with the event, which I have no clue how to do.
Thanks for help!
Got it. I need to attach dataTablesExt to a global variable I'm using and not declare it as a variable. So like this:
// globals
var
...;
$.dataTablesExt = {};
Then I can assign functions to it and call them.
I have a plugin that looks like this:
(function($) {
$.fn.plugin_name = function(options) {
var $this = $(this);
var defaults = {
// some defaults
};
options = $.extend({}, defaults, options);
var work = {
action_1: function() {
// do something
},
action_2: function(output) {
alert('hello world');
}
}
that.submit(function(e) {
e.preventDefault();
work.action_1();
});
return $this;
}
})(jQuery);
It's being used like any traditional jquery plugin, by being attached to a page element like so:
$('#search-form').plugin_name({
// overide options
});
My question is, how can I execute the work.action_2() function that's deeply nested inside the plugin? I would like to call it manually from the javascript console in firebug.
My question is, how can I execute the work.action_2() function that's deeply nested inside the plugin?
You can't, it's outside of your scope!
you can't reach private function variables, just like you can't reach my functions...
Create it in a separate utility function if its needed independently, better if its in your own global object.
So you can call it like so: $.myGlobalObj.action_2()
There are many topics related to my question and i have been through most of them, but i haven't got it right. The closest post to my question is the following:
How to call functions that are nested inside a JQuery Plugin?
Below is the jquery plugin i am using. On resize, the element sizes are recalculated. I am now trying to call the function resizeBind() from outside of the jquery plugin and it gives me error
I tried the following combinations to call the function
$.fn.splitter().resizeBind()
$.fn.splitter.resizeBind()
Any ideas, where i am getting wrong?
;(function($){
$.fn.splitter = function(args){
//Other functions ......
$(window).bind("resize", function(){
resizeBind();
});
function resizeBind(){
var top = splitter.offset().top;
var wh = $(window).height();
var ww = $(window).width();
var sh = 0; // scrollbar height
if (ww <0 && !jQuery.browser.msie )
sh = 17;
var footer = parseInt($("#footer").css("height")) || 26;
splitter.css("height", wh-top-footer-sh+"px");
$("#tabsRight").css("height", splitter.height()-30+"px");
$(".contentTabs").css("height", splitter.height()-70+"px");
}
return this.each(function() {
});
};
})(jQuery);
I had the same problem. Those answers on related posts didn't work for my case either. I solved it in a round about way using events.
The example below demonstrates calling a function that multiplies three internal data values by a given multiplier, and returns the result. To call the function, you trigger an event. The handler in turn triggers another event that contains the result. You need to set up a listener for the result event.
Here's the plugin - mostly standard jQuery plugin architecture created by an online wizard:
(function($){
$.foo = function(el, options){
// To avoid scope issues, use 'base' instead of 'this'
var base = this;
// Access to jQuery and DOM versions of element
base.$el = $(el);
base.el = el;
// Add a reverse reference to the DOM object
base.$el.data("foo", base);
base.init = function(){
base.options = $.extend({},$.foo.defaultOptions, options);
// create private data and copy in the options hash
base.private_obj = {};
base.private_obj.value1 = (base.options.opt1);
base.private_obj.value2 = (base.options.opt2);
base.private_obj.value3 = (base.options.opt3);
// make a little element to dump the results into
var ui_element = $('<p>').attr("id","my_paragraph").html(base.private_obj.value1 +" "+ base.private_obj.value2+" " +base.private_obj.value3);
base.$el.append(ui_element);
// this is the handler for the 'get_multiplied_data_please' event.
base.$el.bind('get_multiplied_data_please', function(e,mult) {
bar = {};
bar.v1 = base.private_obj.value1 *mult;
bar.v2 = base.private_obj.value2 *mult;
bar.v3 = base.private_obj.value3 *mult;
base.$el.trigger("here_is_the_multiplied_data", bar);
});
};
base.init();
}
$.foo.defaultOptions = {
opt1: 150,
opt2: 30,
opt3: 100
};
$.fn.foo = function(options){
return this.each(function(){
(new $.foo(this, options));
});
};
})(jQuery);
So, you can attach the object to an element as usual when the document is ready. And at the same time set up a handler for the result event.
$(document).ready(function(){
$('body').foo();
$('body').live('here_is_the_multiplied_data', function(e, data){
console.log("val1:" +data.v1);
console.log("val2:" +data.v2);
console.log("val3:" +data.v3);
$("#my_paragraph").html(data.v1 +" "+ data.v2+" " +data.v3);
});
})
All that's left is to trigger the event and pass it a multiplier value
You could type this into the console - or trigger it from a button that picks out the multiplier from another UI element
$('body').trigger('get_multiplied_data_please', 7);
Disclaimer ;) - I'm quite new to jQuery - sorry if this is using a hammer to crack a nut.
resizeBind function is defined as private so you cannot access it from outside of it's scope. If you want to use it in other scopes you need to define it like that
$.fn.resizeBind = function() { ... }
Then you would call it like that $(selector').resizeBind()
You have defined the resizeBind function in a scope that is different from the global scope. If you dont'use another javascript framework or anything else that uses the $ function (to prevent conflict) you can delete the
(function($){
...
})(jQuery);
statement and in this way the function will be callable everywhere without errors
I didn't test it:
this.resizeBind = function() { .... }