jQuery, passing selectors as option parameters - jquery-plugins

I'm trying to build a simple jquery plugin that can take selectors as parameters. All of the examples I find expect more raw 'properties' (width, color, etc) than actual selectors. Are there any good ways to do this?
I found this article : Passing jquery selector to sub-function within a plugin
But I'm still relatively confused.
The goal is kind of like this ...
(function ($) {
$.fn.demonstration = function (options) {
var defaults = {
$selector: null
};
var options = $.extend(defaults, options);
return this.each(function () {
alert($selector.attr('id'));
});
};
})(jQuery);
$('body').demonstration({ $selector: $('#canvas') });

A selector is nothing more than a string. As long as you wrap any access to a jQuery() ($) call, people can pass in pretty much anything (a selector string, a jQuery object, a DOM element, etc.)
Edit: Saw you added code, in this case you should access it by $(options.$selector).attr('id').
Out of curiosity, why the $ before selector?

Related

jQuery autocomplete styling on only certain results

Is it possible to add styling to only some of the results returned in an autocomplete dropdown?
The code below works fine, however, I would like to style the individual results based on the value of data[x].restricted. When it is true, I still want to display those items but disable or grey them out within the autocomplete dropdown list. If data[x].restricted is false then I do not want to apply any additional styling to those items.
source: function (request, response) {
$.ajax({
url: $("#AutoCompleteCustomerNameUrl").val(),
type: "POST",
dataType: "json",
data: {
srchCus: request.term
},
success: function (data) {
var x, array = [];
for (x in data) {
array.push({
label: (data[x].restricted ? 'Restricted Access - ' : '') + data[x].customerName,
name: data[x].customerFullName
});
}
}
});
}
Any assistance on how to accomplish this would be much appreciated.
Approach 1 (feels hacky)
This doesn't feel like a great option, but you could probably do this by using jQuery to target elements based on their text content. Autocomplete suggestions are generated as <li>s, so something like this might work:
$('li:contains("Restricted Access")').addClass('grey');
The question is then when to run that? Those elements are added dynamically of course, after page load, so that would have to run after they've been created - you'd have to run it based on some autocomplete event. Looking through the list in the docs, maybe the open event would be best. A handler for that event will run whenever the menu is opened, so it could add a CSS class to all the just-created suggestions matching that selector. Eg (untested):
$("#selector").autocomplete({
// ... your normal autocomplete code ...
open: function(event, ui) {
// Add a CSS class to those suggestions matching the text
$('li:contains("Restricted Access")').addClass('grey');
}
});
I haven't tested this, as it doesn't feel like the right approach. Below is a much better, tested and working option.
Approach 2 (feels good)
You can also do this using the _renderItem extension point. If you check the example they give there you can see it is the function which actually generates the HTML which shows up as your autocomplete suggestion. If we can customise that, we could do anything - eg check details of the item, add specific CSS classes, etc.
I don't find those docs super clear, but it isn't hard to find examples of it in use, eg the Custom Data example (that #Simon-K linked to in the comments above) shows how to use it:
$("#selector").autocomplete({
// ... your normal autocomplete code ...
}).autocomplete("instance")._renderItem = function(ul, item) {
// Here we have complete control of what is returned, and access to
// the items!
return $("<li>").append("<div>" + item.label ...).appendTo(ul);
};
So with your requirements, we could do something like this:
$("#selector").autocomplete({
// ... your normal autocomplete code ...
}).autocomplete("instance")._renderItem = function(ul, item) {
var style = (item.restricted) ? 'grey' : '';
return $("<li>")
.append("<div class='" + style + "'>" + item.label + "</div>")
.appendTo(ul);
};
And then of course add a CSS class to style those items:
.grey {
color: #ccc;
}
Working JSFiddle.

jQuery Delegate not binding like I want it to

Using jQuery 1.7
I'm having trouble binding a Click event to some dynamically loaded content.
I've looked around, tried .live, .delegate and .on, and I just can't get it to work.
This is my code:
$(".fileexplorer_folderdlg").delegate(".delete", "click", function () {
console.log("Hello world!");
});
The thing is, .fileexplorer_folderdlg is dynamically loaded. If I use .fileexplorer (not dynamically loaded), it works, but I have more elements with the .delete class that I do not wish to bind to (and neither element classes can be renamed or changed for various reasons).
I also tried using .fileexplorer_folderdlg .delete as the .delegate selector, didnt work either!
Of course I could just add another unique class to the elements I wish to bind to, but this really should work, right?
I believe this would work:
$(document).on('click', '.delete', function() {
if ($(this).closest('.fileexplorer_folderdlg').length) {
console.log('hello, world!');
}
});
or even just:
$(document).on('click', '.fileexplorer_folderdlg .delete', function() {
console.log('hello, world!');
});
As you've found, you can't bind on .fileexplorer_folderdlg because it's dynamic. You therefore need to bind on some static element that will contain that element at some point in the future.
Instead, this binds on the document (but will unfortunately fire for every single click on the document thereafter).
EDIT by Jeff
Although the code above did not work, modifying it a bit did the job, although not the most desirable solution.
$(document).on('click', '.delete', function () {
if($(this).closest(".fileexplorer") != null)
console.log("Thanks for your help!");
});
It works, but this event is fired for all other .delete classes, of which there are many. What I do not understand though, is why using .fileexplorer_folderdlg .delete did not work!

My jQuery plugin events not firing on multiple elements

I wrote a jQuery plugin to filter select list options. It works great on one list, but not on more elements: http://jsfiddle.net/vgXPh/4/
$("select.filter").listFilter(); // doesn't work
$("select.filter:first").listFilter(); // works
I don't see any global variables that could be messing it up. Am I calling my bind events correctly? JSLint doesn't complain. What am I doing wrong?
You should probably surround your code with this.each(), like this:
$.fn.listFilter = function() {
this.each(function() {
(...)
});
return this;
};

jQuery Live implementation in Prototype

Element.implement({
addLiveEvent: function(event, selector, fn){
this.addEvent(event, function(e){
var t = $(e.target);
if (!t.match(selector)) return false;
fn.apply(t, [e]);
}.bindWithEvent(this, selector, fn));
}
});
$(document.body).addLiveEvent('click', 'a', function(e){ alert('This is a live event'); });
The above code was done in a similar question to implement .live behaviour in Mootools. I've read the question: Prototype equivalent for jQuery live function.
How do I implement this in Prototype? Probably something that can be implemented like this:
document.liveobserve('click', 'a', function(e){ alert('This is a live event');
Edited to make the question clear.
The simplest (and perhaps not the fastest or best) way would appear to be something like:
Element.live = function(evType, evSelector, evBlock) {
var mySelector = evSelector;
var myBlock = evBlock;
this.observe(evType, function(ev) {
if (ev.target.match(mySelector)) {
evBlock(ev);
}
});
};
The parameters evSelector and evBlock are assigned to local variables so the they are available to the event handler (It's a closure). The passed block evBlock gets passed the event object just like a normal Prototype event handler.
It should be noted this is going to handle every event of type 'evType' so if it's a mouseMove/mouseOver this is going to make your page slow. Also FireBug will probably just go to sleep on you due to the number of events that it has to single step through.
EDIT: Changed as per comments

prototype get inner html of multiple classes

I am new to prototype and finding it a lot more difficult than jquery. All i want to do is get the inner html of various classes.
$$('.book').each(function() {
var msg = this.down(".information");
alert(msg.innerHTML);
//new Tip(this, msg.innerHTML, {stem: 'topLeft', hook: { tip: 'topLeft', mouse: true }, offset: { x: 14, y: 14 }});
});
I'm trying to create tooltips for multiple items, but I'm not even getting the alert.
I think you can probably prevent the extra dom work of down() like this:
$$('.book .information').each(function(book) {
alert(book.innerHTML);
});
remember you also have the ability to use advanced CSS2 and CSS3 selectors in prototype like this for example:
$$('.book a[rel]').each(function(el) {
alert(el.rel);
});
see the bottom of this page for more examples http://www.prototypejs.org/api/utility/dollar-dollar
The this variable is not pointing to the element you're iterating over in Prototype, you have to explicitly use a parameter:
$$('.book').each(function(book) {
var msg = book.down(".information");
alert(msg.innerHTML);
});

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