ui/webui/resources/js/i18n_template_no_process.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview This is a simple template engine inspired by JsTemplates
   7  * optimized for i18n.
   8  *
   9  * It currently supports three handlers:
  10  *
  11  *   * i18n-content which sets the textContent of the element.
  12  *
  13  *     <span i18n-content="myContent"></span>
  14  *
  15  *   * i18n-options which generates <option> elements for a <select>.
  16  *
  17  *     <select i18n-options="myOptionList"></select>
  18  *
  19  *   * i18n-values is a list of attribute-value or property-value pairs.
  20  *     Properties are prefixed with a '.' and can contain nested properties.
  21  *
  22  *     <span i18n-values="title:myTitle;.style.fontSize:fontSize"></span>
  23  *
  24  * This file is a copy of i18n_template.js, with minor tweaks to support using
  25  * load_time_data.js. It should replace i18n_template.js eventually.
  26  */
  27
  28 var i18nTemplate = (function() {
  29   /**
  30    * This provides the handlers for the templating engine. The key is used as
  31    * the attribute name and the value is the function that gets called for every
  32    * single node that has this attribute.
  33    * @type {Object}
  34    */
  35   var handlers = {
  36     /**
  37      * This handler sets the textContent of the element.
  38      * @param {HTMLElement} element The node to modify.
  39      * @param {string} key The name of the value in the dictionary.
  40      * @param {LoadTimeData} dictionary The dictionary of strings to draw from.
  41      */
  42     'i18n-content': function(element, key, dictionary) {
  43       element.textContent = dictionary.getString(key);
  44     },
  45
  46     /**
  47      * This handler adds options to a <select> element.
  48      * @param {HTMLElement} select The node to modify.
  49      * @param {string} key The name of the value in the dictionary. It should
  50      *     identify an array of values to initialize an <option>. Each value,
  51      *     if a pair, represents [content, value]. Otherwise, it should be a
  52      *     content string with no value.
  53      * @param {LoadTimeData} dictionary The dictionary of strings to draw from.
  54      */
  55     'i18n-options': function(select, key, dictionary) {
  56       var options = dictionary.getValue(key);
  57       options.forEach(function(optionData) {
  58         var option = typeof optionData == 'string' ?
  59             new Option(optionData) :
  60             new Option(optionData[1], optionData[0]);
  61         select.appendChild(option);
  62       });
  63     },
  64
  65     /**
  66      * This is used to set HTML attributes and DOM properties. The syntax is:
  67      *   attributename:key;
  68      *   .domProperty:key;
  69      *   .nested.dom.property:key
  70      * @param {HTMLElement} element The node to modify.
  71      * @param {string} attributeAndKeys The path of the attribute to modify
  72      *     followed by a colon, and the name of the value in the dictionary.
  73      *     Multiple attribute/key pairs may be separated by semicolons.
  74      * @param {LoadTimeData} dictionary The dictionary of strings to draw from.
  75      */
  76     'i18n-values': function(element, attributeAndKeys, dictionary) {
  77       var parts = attributeAndKeys.replace(/\s/g, '').split(/;/);
  78       parts.forEach(function(part) {
  79         if (!part)
  80           return;
  81
  82         var attributeAndKeyPair = part.match(/^([^:]+):(.+)$/);
  83         if (!attributeAndKeyPair)
  84           throw new Error('malformed i18n-values: ' + attributeAndKeys);
  85
  86         var propName = attributeAndKeyPair[1];
  87         var propExpr = attributeAndKeyPair[2];
  88
  89         var value = dictionary.getValue(propExpr);
  90
  91         // Allow a property of the form '.foo.bar' to assign a value into
  92         // element.foo.bar.
  93         if (propName[0] == '.') {
  94           var path = propName.slice(1).split('.');
  95           var targetObject = element;
  96           while (targetObject && path.length > 1) {
  97             targetObject = targetObject[path.shift()];
  98           }
  99           if (targetObject) {
 100             targetObject[path] = value;
 101             // In case we set innerHTML (ignoring others) we need to
 102             // recursively check the content.
 103             if (path == 'innerHTML')
 104               process(element, dictionary);
 105           }
 106         } else {
 107           element.setAttribute(propName, value);
 108         }
 109       });
 110     }
 111   };
 112
 113   var attributeNames = Object.keys(handlers);
 114   var selector = '[' + attributeNames.join('],[') + ']';
 115
 116   /**
 117    * Processes a DOM tree with the {@code dictionary} map.
 118    * @param {HTMLElement} node The root of the DOM tree to process.
 119    * @param {LoadTimeData} dictionary The dictionary to draw from.
 120    */
 121   function process(node, dictionary) {
 122     var elements = node.querySelectorAll(selector);
 123     for (var element, i = 0; element = elements[i]; i++) {
 124       for (var j = 0; j < attributeNames.length; j++) {
 125         var name = attributeNames[j];
 126         var attribute = element.getAttribute(name);
 127         if (attribute != null)
 128           handlers[name](element, attribute, dictionary);
 129       }
 130     }
 131   }
 132
 133   return {
 134     process: process
 135   };
 136 }());