playground
/
echo
mirror of https://github.com/toddmotto/echo.git
1
0
Fork 0
Code Issues Releases Activity
Browse Source

Small cleanups, improved structure, reduce size

pull/50/head
Todd Motto 11 years ago
parent
094ad3de89
commit
9921a9f10d
6 changed files with 145 additions and 247 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 13
      .jshintrc
  2. 39
      README.md
  3. 167
      dist/echo.js
  4. 4
      dist/echo.min.js
  5. 4
      package.json
  6. 165
      src/echo.js

13
.jshintrc
Unescape View File

@ -4,18 +4,19 @@
"esnext": true,
"bitwise": true,
"camelcase": true,
"curly": true,
"curly": false,
"eqeqeq": true,
"immed": true,
"indent": 2,
"immed": true,
"latedef": true,
"newcap": true,
"noarg": true,
"quotmark": "single",
"regexp": true,
"undef": true,
"unused": true,
"strict": true,
"trailing": true,
"smarttabs": true
"unused": false,
"trailing": false,
"globals" : {
"define": true
}
}

39
README.md
Unescape View File

@ -1,6 +1,6 @@
# Echo [![Build Status](https://travis-ci.org/toddmotto/echo.png)](https://travis-ci.org/toddmotto/echo)
Echo is a standalone JavaScript lazy-loading image tool. Echo is fast, less than 1KB and uses HTML5 data-* attributes. Check out a [demo](http://toddmotto.com/labs/echo). Echo works in IE8+.
Echo is a standalone JavaScript lazy-loading image micro-library. Echo is fast, 2KB, and uses HTML5 data-* attributes for simple. Check out a [demo](http://toddmotto.com/labs/echo). Echo works in IE8+.
```
bower install echojs
@ -15,19 +15,21 @@ Using Echo.js is simple, just add the image you wish to load to a `data-echo` a
<script src="dist/echo.js"></script>
<script>
Echo.init({
echo.init({
offset: 100,
throttle: 250,
unload: false,
callback: function(element, op){ console.log(element, "has been", op+'ed')}
callback: function (element, op) {
console.log(element, 'has been', op + 'ed')
}
});
// Echo.render(); is also available for non-scroll callbacks
// echo.render(); is also available for non-scroll callbacks
</script>
</body>
```
## .init() API (options)
## .init() (options)
The `init()` API takes a few options
@ -83,7 +85,7 @@ Type: `Function`
The callback will be passed the element that has been updated and what the update operation was (ie `load` or `unload`). This can be useful if you want to add a class like `loaded` to the element. Or do some logging.
```js
Echo.init({
echo.init({
callback: function(element, op) {
if(op === 'load') {
elemend.classList.add('loaded');
@ -94,16 +96,15 @@ Echo.init({
});
```
## .render() API
## .render()
Echo's callback `render()` can be used to make Echo poll your images when you're not scrolling, for instance if you've got a filter layout that swaps images but does not scroll, you need to call the internal functions without scrolling. Use `render()` for this:
```js
Echo.render();
echo.render();
```
Using `render()` is also throttled, which means you can bind it to a `window.onresize` event and it will be optimised for performance in the same way `window.onscroll` is.
Using `render()` is also throttled, which means you can bind it to an `onresize` event and it will be optimised for performance in the same way `onscroll` is.
## Manual installation
Drop your files into your required folders, make sure you're using the file(s) from the `dist` folder, which is the compiled production-ready code. Ensure you place the script before the closing `</body>` tag so the DOM tree is populated when the script runs.
@ -115,22 +116,8 @@ Add the image that needs to load when it's visible inside the viewport in a `dat
<img src="img/blank.gif" alt="Photo" data-echo="img/photo.jpg">
```
## Scaffolding
Project files and folder structure.
```
├── dist/
│ ├── echo.js
│ └── echo.min.js
├── src/
│ └── echo.js
├── .editorconfig
├── .gitignore
├── .jshintrc
├── .travis.yml
├── Gruntfile.js
└── package.json
```
## Contributing
In lieu of a formal style guide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.
## License
MIT license

167
dist/echo.js vendored
Unescape View File

@ -1,102 +1,40 @@
/*! Echo v1.5.0 | (c) 2014 @toddmotto | MIT license | github.com/toddmotto/echo */
window.Echo = (function (global, document, undefined) {
/*! echo.js v1.6.0 | (c) 2014 @toddmotto | MIT license | github.com/toddmotto/echo */
(function (root, factory) {
if (typeof define === 'function' && define.amd) {
define(factory);
} else if (typeof exports === 'object') {
module.exports = factory;
} else {
root.echo = factory(root);
}
})(this, function (root) {
'use strict';
/**
* callback - initialized to a no-op so that no validations on it's presence need to be made
* @type {Function}
*/
var callback = function(){};
var exports = {};
var callback = function () {};
/**
* offset, throttle, poll, unload vars
*/
var offset, throttle, poll, unload;
var offset, poll, throttle, unload;
/**
* _inView
* @private
* @param {Element} element Image element
* @returns {Boolean} Is element in viewport
*/
var _inView = function (element, view) {
var inView = function (element, view) {
var box = element.getBoundingClientRect();
return (box.right >= view.l && box.bottom >= view.t && box.left <= view.r && box.top <= view.b);
};
/**
* _pollImages Loop through the images if present
* or remove all event listeners
* @private
*/
var _pollImages = function () {
var src,
i,
elem,
view,
nodes = document.querySelectorAll('img[data-echo]'),
length = nodes.length;
view = {
l: 0 - offset.l,
t: 0 - offset.t,
b: (window.innerHeight || document.documentElement.clientHeight) + offset.b,
r: (window.innerWidth || document.documentElement.clientWidth) + offset.r
};
for(i=0; i<length; i++) {
elem = nodes[i];
if(_inView(elem, view)) {
if(unload) {
elem.setAttribute('data-echo-placeholder', elem.src);
}
elem.src = elem.getAttribute('data-echo');
if(!unload) {
elem.removeAttribute('data-echo');
}
callback(elem, 'load');
} else if(unload && !!(src = elem.getAttribute('data-echo-placeholder'))) {
elem.src = src;
elem.removeAttribute('data-echo-placeholder');
callback(elem, 'unload');
}
}
if(!length) {
detach();
}
};
/**
* _throttle Sensible event firing
* @private
*/
var _throttle = function () {
var debounce = function () {
clearTimeout(poll);
poll = setTimeout(_pollImages, throttle);
poll = setTimeout(exports.render, throttle);
};
/**
* init Module init function
* @param {Object} [opts] Passed in Object with options
* @param {Number|String} [opts.throttle]
* @param {Number|String} [opts.offset]
* @param {Number|String} [opts.offsetBottom]
* @param {Number|String} [opts.offsetTop]
* @param {Number|String} [opts.offsetLeft]
* @param {Number|String} [opts.offsetRight]
* @param {Boolean} [opts.unload]
* @param {Function} [opts.callback]
*/
var init = function (opts) {
exports.init = function (opts) {
opts = opts || {};
var offsetAll = opts.offset || 0;
var offsetVertical = opts.offsetVertical || offsetAll;
var offsetHorizontal = opts.offsetHorizontal || offsetAll;
function optionToInt(opt, fallback) {
var optionToInt = function (opt, fallback) {
return parseInt(opt || fallback, 10);
}
};
offset = {
t: optionToInt(opts.offsetTop, offsetVertical),
b: optionToInt(opts.offsetBottom, offsetVertical),
@ -106,40 +44,57 @@ window.Echo = (function (global, document, undefined) {
throttle = optionToInt(opts.throttle, 250);
unload = !!opts.unload;
callback = opts.callback || callback;
_pollImages();
exports.render();
if (document.addEventListener) {
global.addEventListener('scroll', _throttle, false);
global.addEventListener('load', _throttle, false);
root.addEventListener('scroll', debounce, false);
root.addEventListener('load', debounce, false);
} else {
global.attachEvent('onscroll', _throttle);
global.attachEvent('onload', _throttle);
root.attachEvent('onscroll', debounce);
root.attachEvent('onload', debounce);
}
};
exports.render = function () {
var nodes = document.querySelectorAll('img[data-echo]');
var length = nodes.length;
var src, elem;
var view = {
l: 0 - offset.l,
t: 0 - offset.t,
b: (root.innerHeight || document.documentElement.clientHeight) + offset.b,
r: (root.innerWidth || document.documentElement.clientWidth) + offset.r
};
for (var i = 0; i < length; i++) {
elem = nodes[i];
if (inView(elem, view)) {
if (unload) {
elem.setAttribute('data-echo-placeholder', elem.src);
}
elem.src = elem.getAttribute('data-echo');
if (!unload) {
elem.removeAttribute('data-echo');
}
callback(elem, 'load');
} else if (unload && !!(src = elem.getAttribute('data-echo-placeholder'))) {
elem.src = src;
elem.removeAttribute('data-echo-placeholder');
callback(elem, 'unload');
}
}
if (!length) {
exports.detach();
}
};
/**
* detach remove listeners
*/
var detach = function() {
exports.detach = function () {
if (document.removeEventListener) {
global.removeEventListener('scroll', _throttle);
root.removeEventListener('scroll', debounce);
} else {
global.detachEvent('onscroll', _throttle);
root.detachEvent('onscroll', debounce);
}
clearTimeout(poll);
};
/**
* return Public methods
* @returns {Object}
*/
return {
init: init,
detach: detach,
render: _pollImages
};
return exports;
})(this, document);
});

4
dist/echo.min.js vendored
Unescape View File

@ -1,2 +1,2 @@
/*! Echo v1.5.0 | (c) 2014 @toddmotto | MIT license | github.com/toddmotto/echo */
window.Echo=function(a,b){"use strict";var c,d,e,f,g=function(){},h=function(a,b){var c=a.getBoundingClientRect();return c.right>=b.l&&c.bottom>=b.t&&c.left<=b.r&&c.top<=b.b},i=function(){var a,d,e,i,j=b.querySelectorAll("img[data-echo]"),k=j.length;for(i={l:0-c.l,t:0-c.t,b:(window.innerHeight||b.documentElement.clientHeight)+c.b,r:(window.innerWidth||b.documentElement.clientWidth)+c.r},d=0;k>d;d++)e=j[d],h(e,i)?(f&&e.setAttribute("data-echo-placeholder",e.src),e.src=e.getAttribute("data-echo"),f||e.removeAttribute("data-echo"),g(e,"load")):f&&(a=e.getAttribute("data-echo-placeholder"))&&(e.src=a,e.removeAttribute("data-echo-placeholder"),g(e,"unload"));k||l()},j=function(){clearTimeout(e),e=setTimeout(i,d)},k=function(e){function h(a,b){return parseInt(a||b,10)}e=e||{};var k=e.offset||0,l=e.offsetVertical||k,m=e.offsetHorizontal||k;c={t:h(e.offsetTop,l),b:h(e.offsetBottom,l),l:h(e.offsetLeft,m),r:h(e.offsetRight,m)},d=h(e.throttle,250),f=!!e.unload,g=e.callback||g,i(),b.addEventListener?(a.addEventListener("scroll",j,!1),a.addEventListener("load",j,!1)):(a.attachEvent("onscroll",j),a.attachEvent("onload",j))},l=function(){b.removeEventListener?a.removeEventListener("scroll",j):a.detachEvent("onscroll",j),clearTimeout(e)};return{init:k,detach:l,render:i}}(this,document);
/*! echo.js v1.6.0 | (c) 2014 @toddmotto | MIT license | github.com/toddmotto/echo */
!function(a,b){"function"==typeof define&&define.amd?define(b):"object"==typeof exports?module.exports=b:a.echo=b(a)}(this,function(a){"use strict";var b,c,d,e,f={},g=function(){},h=function(a,b){var c=a.getBoundingClientRect();return c.right>=b.l&&c.bottom>=b.t&&c.left<=b.r&&c.top<=b.b},i=function(){clearTimeout(c),c=setTimeout(f.render,d)};return f.init=function(c){c=c||{};var h=c.offset||0,j=c.offsetVertical||h,k=c.offsetHorizontal||h,l=function(a,b){return parseInt(a||b,10)};b={t:l(c.offsetTop,j),b:l(c.offsetBottom,j),l:l(c.offsetLeft,k),r:l(c.offsetRight,k)},d=l(c.throttle,250),e=!!c.unload,g=c.callback||g,f.render(),document.addEventListener?(a.addEventListener("scroll",i,!1),a.addEventListener("load",i,!1)):(a.attachEvent("onscroll",i),a.attachEvent("onload",i))},f.render=function(){for(var c,d,i=document.querySelectorAll("img[data-echo]"),j=i.length,k={l:0-b.l,t:0-b.t,b:(a.innerHeight||document.documentElement.clientHeight)+b.b,r:(a.innerWidth||document.documentElement.clientWidth)+b.r},l=0;j>l;l++)d=i[l],h(d,k)?(e&&d.setAttribute("data-echo-placeholder",d.src),d.src=d.getAttribute("data-echo"),e||d.removeAttribute("data-echo"),g(d,"load")):e&&(c=d.getAttribute("data-echo-placeholder"))&&(d.src=c,d.removeAttribute("data-echo-placeholder"),g(d,"unload"));j||f.detach()},f.detach=function(){document.removeEventListener?a.removeEventListener("scroll",i):a.detachEvent("onscroll",i),clearTimeout(c)},f});

4
package.json
Unescape View File

@ -1,6 +1,6 @@
{
"name": "Echo",
"version": "1.5.0",
"name": "echo.js",
"version": "1.6.0",
"homepage": "https://github.com/toddmotto/echo",
"author": "Todd Motto",
"description": "Lazy-loading with data-* attributes, offset and throttle options",

165
src/echo.js
Unescape View File

@ -1,101 +1,39 @@
window.Echo = (function (global, document, undefined) {
(function (root, factory) {
if (typeof define === 'function' && define.amd) {
define(factory);
} else if (typeof exports === 'object') {
module.exports = factory;
} else {
root.echo = factory(root);
}
})(this, function (root) {
'use strict';
/**
* callback - initialized to a no-op so that no validations on it's presence need to be made
* @type {Function}
*/
var callback = function(){};
var exports = {};
var callback = function () {};
/**
* offset, throttle, poll, unload vars
*/
var offset, throttle, poll, unload;
var offset, poll, throttle, unload;
/**
* _inView
* @private
* @param {Element} element Image element
* @returns {Boolean} Is element in viewport
*/
var _inView = function (element, view) {
var inView = function (element, view) {
var box = element.getBoundingClientRect();
return (box.right >= view.l && box.bottom >= view.t && box.left <= view.r && box.top <= view.b);
};
/**
* _pollImages Loop through the images if present
* or remove all event listeners
* @private
*/
var _pollImages = function () {
var src,
i,
elem,
view,
nodes = document.querySelectorAll('img[data-echo]'),
length = nodes.length;
view = {
l: 0 - offset.l,
t: 0 - offset.t,
b: (window.innerHeight || document.documentElement.clientHeight) + offset.b,
r: (window.innerWidth || document.documentElement.clientWidth) + offset.r
};
for(i=0; i<length; i++) {
elem = nodes[i];
if(_inView(elem, view)) {
if(unload) {
elem.setAttribute('data-echo-placeholder', elem.src);
}
elem.src = elem.getAttribute('data-echo');
if(!unload) {
elem.removeAttribute('data-echo');
}
callback(elem, 'load');
} else if(unload && !!(src = elem.getAttribute('data-echo-placeholder'))) {
elem.src = src;
elem.removeAttribute('data-echo-placeholder');
callback(elem, 'unload');
}
}
if(!length) {
detach();
}
};
/**
* _throttle Sensible event firing
* @private
*/
var _throttle = function () {
var debounce = function () {
clearTimeout(poll);
poll = setTimeout(_pollImages, throttle);
poll = setTimeout(exports.render, throttle);
};
/**
* init Module init function
* @param {Object} [opts] Passed in Object with options
* @param {Number|String} [opts.throttle]
* @param {Number|String} [opts.offset]
* @param {Number|String} [opts.offsetBottom]
* @param {Number|String} [opts.offsetTop]
* @param {Number|String} [opts.offsetLeft]
* @param {Number|String} [opts.offsetRight]
* @param {Boolean} [opts.unload]
* @param {Function} [opts.callback]
*/
var init = function (opts) {
exports.init = function (opts) {
opts = opts || {};
var offsetAll = opts.offset || 0;
var offsetVertical = opts.offsetVertical || offsetAll;
var offsetHorizontal = opts.offsetHorizontal || offsetAll;
function optionToInt(opt, fallback) {
var optionToInt = function (opt, fallback) {
return parseInt(opt || fallback, 10);
}
};
offset = {
t: optionToInt(opts.offsetTop, offsetVertical),
b: optionToInt(opts.offsetBottom, offsetVertical),
@ -105,40 +43,57 @@ window.Echo = (function (global, document, undefined) {
throttle = optionToInt(opts.throttle, 250);
unload = !!opts.unload;
callback = opts.callback || callback;
_pollImages();
exports.render();
if (document.addEventListener) {
global.addEventListener('scroll', _throttle, false);
global.addEventListener('load', _throttle, false);
root.addEventListener('scroll', debounce, false);
root.addEventListener('load', debounce, false);
} else {
global.attachEvent('onscroll', _throttle);
global.attachEvent('onload', _throttle);
root.attachEvent('onscroll', debounce);
root.attachEvent('onload', debounce);
}
};
exports.render = function () {
var nodes = document.querySelectorAll('img[data-echo]');
var length = nodes.length;
var src, elem;
var view = {
l: 0 - offset.l,
t: 0 - offset.t,
b: (root.innerHeight || document.documentElement.clientHeight) + offset.b,
r: (root.innerWidth || document.documentElement.clientWidth) + offset.r
};
for (var i = 0; i < length; i++) {
elem = nodes[i];
if (inView(elem, view)) {
if (unload) {
elem.setAttribute('data-echo-placeholder', elem.src);
}
elem.src = elem.getAttribute('data-echo');
if (!unload) {
elem.removeAttribute('data-echo');
}
callback(elem, 'load');
} else if (unload && !!(src = elem.getAttribute('data-echo-placeholder'))) {
elem.src = src;
elem.removeAttribute('data-echo-placeholder');
callback(elem, 'unload');
}
}
if (!length) {
exports.detach();
}
};
/**
* detach remove listeners
*/
var detach = function() {
exports.detach = function () {
if (document.removeEventListener) {
global.removeEventListener('scroll', _throttle);
root.removeEventListener('scroll', debounce);
} else {
global.detachEvent('onscroll', _throttle);
root.detachEvent('onscroll', debounce);
}
clearTimeout(poll);
};
/**
* return Public methods
* @returns {Object}
*/
return {
init: init,
detach: detach,
render: _pollImages
};
return exports;
})(this, document);
});

Write Preview
Loading…
Cancel
Save