toloframework/ker/mod/tfw.hash-watcher.js

Javascript/HTML/CSS compiler for Firefox OS or nodewebkit apps using modules in the nodejs style.

/**
 * The HASH is a very convenient way to deal with the browser history.
 * You can use the `:target` CSS selector, but there are few annoying caveats.
 * This module is a watcher for hash changes. Just pass it a callback as argument.
 * It will be called as soon as the hash changed.
 */
var Listeners = require( "tfw.listeners" );

var lastHash = "?random-hash." + Date.now();
var timer = 0;
var hash = '';
var args = [];
var listeners = new Listeners();

module.exports = function ( onChange ) {
  listeners.add( onChange );
  if ( !timer ) {
    timer = window.setInterval(
      function () {
        var currentHash = window.location.hash;
        if ( lastHash == currentHash ) return;
        lastHash = currentHash;
        if ( currentHash.charAt( 0 ) == '#' ) {
          currentHash = currentHash.substr( 1 );
        }
        hash = currentHash;
        args = currentHash.split( "/" ).map( decodeURI );
        listeners.fire( args, window.location.hash );
      },
      50
    );
  }
};


module.exports.args = function () {
  return args;
};

module.exports.hash = function () {
  return hash;
};