jquery – Daniel X's Blog

LiveEdit

You know those edit in place plugins for jQuery? Well I couldn’t find any that met these two criteria:

Work on elements not yet in the DOM
Didn’t post anything to the server

Now the first requirement probably makes a lot of sense to you, but I bet you’re wondering about the second one. In these crazy mixed up times with rich HTML5 apps, I don’t want to post to the server often. Maybe I’m using local storage, or perhaps I just want to send a big heap of JSON now and again, but I definitely don’t want to post every time anyone changes the value of an editable field.

So after examining all the terrible options (classic first step when choosing jQuery plugins) I decided to throw my own terrible option into the mix.

(($) ->
  $.fn.liveEdit = () ->
    this.live 'dblclick', () ->
      $this = $(this)

      return if $this.is("input")

      textInput = $("",
        class: $this.attr("class")
        "data-origType": this.tagName
        id: if id = $this.attr("id") then id else null
        type: "text"
        value: $.trim($this.text())
      )

      $this.replaceWith textInput

      textInput.focus().select()

    this.live 'blur keydown', (event) ->
      if event.type == "keydown"
        return unless event.which == 13 || event.which == 9

      $this = $(this)

      return if $this.data("removed")
      return unless $this.is("input")

      $this.attr("data-removed", true)

      $this.replaceWith $("",
        class: $this.attr("class")
        id: if id = $this.attr("id") then id else null
        text: $this.val()
      )

    return this

)(jQuery)

There are two tricks here. The first is that this plugin is really a macro that makes two calls to live. The second is that the editable content keeps it’s same id and class when switched out to a text field, so as long as your selector is not based on the element type it will work. There’s plenty of room for improvements, but this is a super simple first step that meets my needs. Enjoy!

jQuery Drag Image From Desktop Plugin

Here’s the CoffeeScript for a jQuery plugin I wrote that makes accepting images dragged in from the desktop super easy. The event.fix part at the beginning is because jQuery currently doesn’t pass on the dataTransfer attribute of events. Once that’s taken care of we create the plugin.

(($) ->
  $.event.fix = ((originalFix) ->
    (event) ->
      event = originalFix.apply(this, arguments)

      if event.type.indexOf('drag') == 0 || event.type.indexOf('drop') == 0
        event.dataTransfer = event.originalEvent.dataTransfer

      event

  )($.event.fix)

  $.fn.dropImageReader = (callback) ->
    stopFn = (event) ->
      event.stopPropagation()
      event.preventDefault()

    this.each () ->
      element = this
      $this = $(this)

      $this.bind 'dragenter dragover dragleave', stopFn

      $this.bind 'drop', (event) ->
        stopFn(event)

        Array.prototype.forEach.call event.dataTransfer.files, (file) ->
          imageType = /image.*/
          if !file.type.match(imageType)
            return

          reader = new FileReader()

          reader.onload = (evt) ->
            callback.call(element, file, evt)

          reader.readAsDataURL(file)

)(jQuery)

The plugin takes a callback that will be called when any of the matched elements receive an image file via the drop event. Here’s an example usage:

$(".tiles").dropImageReader (file, event) ->
  img = $ "",
    alt: file.name
    src: event.target.result
    title: file.name

  $(this).append img

For image drops all you really care about is the file name and the data url, but if for some reason you need different file results here’s the line to modify: reader.readAsDataURL(file). You can also extend or alter what is passed to the callback if this is too mundane for your needs.

And here’s the JS version for anyone eager to copy/paste:

  (function() {
    $.event.fix = (function(originalFix) {
      return function(event) {
        event = originalFix.apply(this, arguments);

        if (event.type.indexOf('drag') === 0 || event.type.indexOf('drop') === 0) {
          event.dataTransfer = event.originalEvent.dataTransfer;
        }

        return event;
      };
    })($.event.fix);

    $.fn.dropImageReader = function(callback) {
      var stopFn;

      stopFn = function(event) {
        event.stopPropagation();
        event.preventDefault();
      };

      return this.each(function() {
        var $this, element;

        element = this;
        $this = $(this);

        $this.bind('dragenter dragover dragleave', stopFn);

        $this.bind('drop', function(event) {
          stopFn(event);

          Array.prototype.forEach.call(event.dataTransfer.files, function(file) {
            var imageType, reader;

            imageType = /image.*/;
            if (!file.type.match(imageType)) {
              return;
            }

            reader = new FileReader();

            reader.onload = function(evt) {
              return callback.call(element, file, evt);
            };

            reader.readAsDataURL(file);
          });
        });
      });
    };
  })(jQuery);

Happy image dropping!

jQuery style events

jQuery events are cool. But what if you want to trigger some events but not extend all your JavaScript objects to jQuery ones? If you are drawing thousands and thousands of these objects to screen you probably don’t want to worry about the overhead of making them jQuery objects.

Here’s how you can write your own simple jQuery style events:

function Meteor() {
  var eventCallbacks = {
    'destroy': alert('destroyed')
  };

  var destroyed = false;

  var self = {
    bind: function(event, callback) {
      eventCallbacks[event] = callback;
    },
    destroy: function() {
      if (!destroyed) {
        destroyed = true;
        self.trigger('destroy');
      }
    },
    explode: function() {
      // Kaboom
    },
    trigger: function(event) {
      eventCallbacks[event](self);
    },
  };
  return self;
}

Here’s how you use it

var meteor = Meteor();
meteor.bind('destroy', function() {
  meteor.explode();
});

...

meteor.destroy();

jqcolor: A jQuery Plugin port of jscolor

That’s right, my idea of a great Sunday afternoon is porting someone else’s code!

At first I was thinking, “I should email this guy and tell him to make a jQuery plugin”. But then I thought, “I’m the one who needs the jQuery plugin…” so I made it. Maybe now I’ll email him and say “I made a jQuery plugin for your color picker”.

Usage:

jQuery(‘input.color’).colorPicker();

This port is from the 1.0.9 version. jscolor was completely rewritten in 1.1.0 and looked like it had some regressions though it is at 1.2.3 now. The newer version is twice as big, still not a jQuery plugin, and also still missing hundreds of semi-colons, so I decided to stick to what I know and work on the smaller version.

So now it is a clunky jQuery plugin. There are still several spots where the syntax could be improved to take advantage of jQuery, but since there are no tests, and I don’t have a bunch of different browers to QA on, I decided to leave it alone as much as possible.

Source on github.

Two Column Google Greasemonkey Script

I remember installing a userscript that would display Google search results in two columns in days of yore. Then one day it stopped working. All the other Google userscripts were massive customize everything about Google ever. I just want two columns homie, and favicons, but I’ve already got the FF plugin for that.

So here it is, the amazing remake that is as good as the original… Two Column Google, nothing fancy, just two columns.

jQuery Selector Tester

The latest release in an ongoing bender of Greasemonkey scripts involving jQuery: the jQuery Selector Tester!

This little guy will hang out on your internet and highlight all the elements that match the selectors you type in. Indispensible for development! It doesn’t remember where you leave it on the page yet so it’s probably easiest to turn on only when needed.

Highlighting all anchors that are descendants of h3

Find some more of my jQuery Greasemonkey scripts here. They are sometimes ahead and sometimes behind what I post on the blog.

How to load jQuery UI CSS In Greasemonkey

// ==UserScript==
// @name           Test
// @namespace      http://strd6.com
// @description    jquery-ui-1.6rc6 Resource Include Test
// @include        *
//
// @resource       jQuery               http://ajax.googleapis.com/ajax/libs/jquery/1.3.1/jquery.min.js
// @resource       jQueryUI             http://strd6.com/stuff/jqui/jquery-ui-personalized-1.6rc6.min.js
//
// @resource       jQueryUICSS          http://strd6.com/stuff/jqui/theme/ui.all.css
//
// @resource    ui-bg_diagonals-thick_18_b81900_40x40.png       http://strd6.com/stuff/jqui/theme/images/ui-bg_diagonals-thick_18_b81900_40x40.png
// @resource    ui-bg_glass_100_f6f6f6_1x400.png                http://strd6.com/stuff/jqui/theme/images/ui-bg_glass_100_f6f6f6_1x400.png
// @resource    ui-bg_diagonals-thick_20_666666_40x40.png       http://strd6.com/stuff/jqui/theme/images/ui-bg_diagonals-thick_20_666666_40x40.png
// @resource    ui-bg_glass_65_ffffff_1x400.png                 http://strd6.com/stuff/jqui/theme/images/ui-bg_glass_65_ffffff_1x400.png
// @resource    ui-bg_gloss-wave_35_f6a828_500x100.png          http://strd6.com/stuff/jqui/theme/images/ui-bg_gloss-wave_35_f6a828_500x100.png
// @resource    ui-icons_222222_256x240.png                     http://strd6.com/stuff/jqui/theme/images/ui-icons_222222_256x240.png
// @resource    ui-bg_flat_10_000000_40x100.png                 http://strd6.com/stuff/jqui/theme/images/ui-bg_flat_10_000000_40x100.png
// @resource    ui-icons_ef8c08_256x240.png                     http://strd6.com/stuff/jqui/theme/images/ui-icons_ef8c08_256x240.png
// @resource    ui-icons_ffd27a_256x240.png                     http://strd6.com/stuff/jqui/theme/images/ui-icons_ffd27a_256x240.png
// @resource    ui-bg_glass_100_fdf5ce_1x400.png                http://strd6.com/stuff/jqui/theme/images/ui-bg_glass_100_fdf5ce_1x400.png
// @resource    ui-icons_228ef1_256x240.png                     http://strd6.com/stuff/jqui/theme/images/ui-icons_228ef1_256x240.png
// @resource    ui-icons_ffffff_256x240.png                     http://strd6.com/stuff/jqui/theme/images/ui-icons_ffffff_256x240.png
// @resource    ui-bg_highlight-soft_75_ffe45c_1x100.png        http://strd6.com/stuff/jqui/theme/images/ui-bg_highlight-soft_75_ffe45c_1x100.png
// @resource    ui-bg_highlight-soft_100_eeeeee_1x100.png       http://strd6.com/stuff/jqui/theme/images/ui-bg_highlight-soft_100_eeeeee_1x100.png
// ==/UserScript==

// Inject jQuery into page... gross hack... for now...
(function() {
  var head = document.getElementsByTagName('head')[0];

  var script = document.createElement('script');
  script.type = 'text/javascript';

  var jQuery = GM_getResourceText('jQuery');
  var jQueryUI = GM_getResourceText('jQueryUI');

  script.innerHTML = jQuery + jQueryUI;
  head.appendChild(script);

  $ = unsafeWindow.$;
})();

// Load UI Styles
(function() {
    var resources = {
      'ui-bg_diagonals-thick_18_b81900_40x40.png': GM_getResourceURL('ui-bg_diagonals-thick_18_b81900_40x40.png'),
      'ui-bg_glass_100_f6f6f6_1x400.png': GM_getResourceURL('ui-bg_glass_100_f6f6f6_1x400.png'),
      'ui-bg_diagonals-thick_20_666666_40x40.png': GM_getResourceURL('ui-bg_diagonals-thick_20_666666_40x40.png'),
      'ui-bg_glass_65_ffffff_1x400.png': GM_getResourceURL('ui-bg_glass_65_ffffff_1x400.png'),
      'ui-bg_gloss-wave_35_f6a828_500x100.png': GM_getResourceURL('ui-bg_gloss-wave_35_f6a828_500x100.png'),
      'ui-icons_222222_256x240.png': GM_getResourceURL('ui-icons_222222_256x240.png'),
      'ui-bg_flat_10_000000_40x100.png': GM_getResourceURL('ui-bg_flat_10_000000_40x100.png'),
      'ui-icons_ef8c08_256x240.png': GM_getResourceURL('ui-icons_ef8c08_256x240.png'),
      'ui-icons_ffd27a_256x240.png': GM_getResourceURL('ui-icons_ffd27a_256x240.png'),
      'ui-bg_glass_100_fdf5ce_1x400.png': GM_getResourceURL('ui-bg_glass_100_fdf5ce_1x400.png'),
      'ui-icons_228ef1_256x240.png': GM_getResourceURL('ui-icons_228ef1_256x240.png'),
      'ui-icons_ffffff_256x240.png': GM_getResourceURL('ui-icons_ffffff_256x240.png'),
      'ui-bg_highlight-soft_75_ffe45c_1x100.png': GM_getResourceURL('ui-bg_highlight-soft_75_ffe45c_1x100.png'),
      'ui-bg_highlight-soft_100_eeeeee_1x100.png': GM_getResourceURL('ui-bg_highlight-soft_100_eeeeee_1x100.png')
    };

    var head = document.getElementsByTagName('head')[0];

    var style = document.createElement('style');
    style.type = 'text/css';

    var css = GM_getResourceText ('jQueryUICSS');
    $.each(resources, function(resourceName, resourceUrl) {
      console.log(resourceName + ': ' + resourceUrl);
      css = css.replace( 'images/' + resourceName, resourceUrl);
    });

    style.innerHTML = css;
    head.appendChild(style);
})();

This technique works whether or not you inject or @require the jQuery js libraries.

The drawback to injecting jQuery is that it is forced to run in the unsafe window context which doesn’t allow you to use GM_* methods in callbacks (this make $.each pretty weak). Also, it breaks pages that define the $ function, but I believe this can be avoided by telling jQuery not to interfere and you can set $ as the local alias within your GM script zone (if that makes any sense).

The drawback of using require is that the UI classes throw exceptions (at least on version 1.6rc6). The dialogs display ok, but you need to catch the exceptions they throw. Also, they throw an exception when you try and drag. I’m pretty sure that it has to do with XPCNativeWrapper. One day UI will be easy in Greasemonkey… one day… Until then this should get you part way there.

The @resource technique works for more than just jQueryUI, use it for your own css and images, at least until jQuery UI gets fixed.

GreasyThug – Greasemonkey, Gears and jQuery

I’ve been called a greasy thug, too. It never stops hurting. So here’s what we’re gonna do: We’re gonna grease ourselves up real good and trash that place with a baseball bat. – Homer

Presenting: GreasyThug

Here’s my problem, I want to develop Greasemonkey scripts. This doesn’t sound like a problem, but JavaScript has a certain terribleness to it, at least in its current browser implementations, and I can never go back to raw JS, NEVER. I’ve also grown accustom to having an interactive console for development and debugging, but Firebug doesn’t have access to Greasemonkey code. And another thing, shouldn’t I be able to make changes to a page, on the fly, and have them persist, without having to dig out my scripts and modify them? Shouldn’t every website be using Gears by now? Wouldn’t it be great to be able to use jQuery in your browser console on every website you go to?

Fact: GreasyThug will make all of your wildest dreams come true.

GreasyThug – Interactive JavaScript Console Features

Built in jQuery functionality.
Google Gears included.
A persistent command history across page reloads and browser restarts.
Drag and drop – remembers where you put it for each site.
Ability to persist micro-scripts and apply them automatically everytime you visit the page.

Warning! GreasyThug is slick (it’s the grease) and dangerous (it’s a thug). An interactive console is essentially a pipe straight into eval(). So… BE CAREFUL! If your thug becomes compromised it will be your house that gets trashed with a baseball bat. Remember, this is eval in the elevated Greasemonkey privilages context, its strength for development is also its weakness for security.

Prerequisites

Demonstration

Let’s spruce up the google search page. Maybe we should make a whole Greasemonkey user script? Nah, that’s a huge hassle now that we already have GreasyThug.

Go to Google.com
A “The website below wants to store information on your computer using Gears” security warning will pop up, as it will do for everydomain that you have GreasyThug enabled for. It’s not really the website using Gears, though some might eventually. Click “Allow”. (This is how the command history and micro-scripts are saved).
Now let’s get cracking! Drag the interactive console to a comfortable location. (It will begin in the top left by default)
Execute some JavaScript statements to get a feel for it. No need for semicolons, we’re not chumps.
Now on to the cool stuff: that white background is a little bland for Valentine’s Day, let’s spice it up. Pop this into your console:
```
$('body').css('background-color', '#F8A')
```
It’s beautiful! See how I can use jQuery? Neat! Also, the up arrow populates the input with my previous command.
Maybe it’s not quite as good looking as I thought, probably best to stick with white… let’s just refresh and forget about this debacle. Back to normal… but the history remembered my command in case I want to try it again.
It is my strong belief that there should be a link to STRd6 right next to everyone’s email address on the Google search page. Obviously this should only be for logged in users… I can only change it for myself though…
```
$('#gb nobr').prepend($('STRd6'))
```
But what about when I refresh… it’ll disappear and all that hard work will be gone?!? Not so good friend:
```
savePrevious()
```
This will store whatever command you last executed to be executed again when you return. You can save many commands. These are those micro-scripts that you’ve been hearing so much about and they are the future.

So is this the end? It is for today. Now imagine sharing micro-scripts with your friends. It’s our internet now. It just takes some elbow grease and a little thuggery.

Feature requests go in the comments.