data-store.php

Basic data store utility -- unfinished
git clone git://git.finwo.net/lib/data-store.php
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domchange.js (2786B)

      1 // See: http://stackoverflow.com/a/3219767
      2 (function (window) {
      3   var last = +new Date();
      4   var delay = 100; // default delay
      5 
      6   // Manage event queue
      7   var stack = [];
      8 
      9   function callback() {
     10     var now = +new Date();
     11     if (now - last > delay) {
     12       for (var i = 0; i < stack.length; i++) {
     13         stack[i]();
     14       }
     15       last = now;
     16     }
     17   }
     18 
     19   // Public interface
     20   var onDomChange = function (fn, newdelay) {
     21     if (newdelay) delay = newdelay;
     22     stack.push(fn);
     23   };
     24 
     25   // Naive approach for compatibility
     26   function naive() {
     27 
     28     var last = document.getElementsByTagName('*');
     29     var lastlen = last.length;
     30     var timer = setTimeout(function check() {
     31 
     32       // get current state of the document
     33       var current = document.getElementsByTagName('*');
     34       var len = current.length;
     35 
     36       // if the length is different
     37       // it's fairly obvious
     38       if (len != lastlen) {
     39         // just make sure the loop finishes early
     40         last = [];
     41       }
     42 
     43       // go check every element in order
     44       for (var i = 0; i < len; i++) {
     45         if (current[i] !== last[i]) {
     46           callback();
     47           last = current;
     48           lastlen = len;
     49           break;
     50         }
     51       }
     52 
     53       // over, and over, and over again
     54       setTimeout(check, delay);
     55 
     56     }, delay);
     57   }
     58 
     59   //
     60   //  Check for mutation events support
     61   //
     62 
     63   var support = {};
     64 
     65   var el = document.documentElement;
     66   var remain = 3;
     67 
     68   // callback for the tests
     69   function decide() {
     70     if (support.DOMNodeInserted) {
     71       window.addEventListener("DOMContentLoaded", function () {
     72         if (support.DOMSubtreeModified) { // for FF 3+, Chrome
     73           el.addEventListener('DOMSubtreeModified', callback, false);
     74         } else { // for FF 2, Safari, Opera 9.6+
     75           el.addEventListener('DOMNodeInserted', callback, false);
     76           el.addEventListener('DOMNodeRemoved', callback, false);
     77         }
     78       }, false);
     79     } else if (document.onpropertychange) { // for IE 5.5+
     80       document.onpropertychange = callback;
     81     } else { // fallback
     82       naive();
     83     }
     84   }
     85 
     86   // checks a particular event
     87   function test(event) {
     88     el.addEventListener(event, function fn() {
     89       support[event] = true;
     90       el.removeEventListener(event, fn, false);
     91       if (--remain === 0) decide();
     92     }, false);
     93   }
     94 
     95   // attach test events
     96   if (window.addEventListener) {
     97     test('DOMSubtreeModified');
     98     test('DOMNodeInserted');
     99     test('DOMNodeRemoved');
    100   } else {
    101     decide();
    102   }
    103 
    104   // do the dummy test
    105   var dummy = document.createElement("div");
    106   el.appendChild(dummy);
    107   el.removeChild(dummy);
    108 
    109   // expose
    110   if (typeof define === 'function' && define.amd) {
    111     define('domchange', function() {
    112       return onDomChange;
    113     })
    114   }
    115   window.onDomChange = onDomChange;
    116 })(window);