diff --git a/core/utils/idgenerator.js b/core/utils/idgenerator.js new file mode 100644 index 000000000..befe53070 --- /dev/null +++ b/core/utils/idgenerator.js @@ -0,0 +1,67 @@ +/** + * @license + * Visual Blocks Editor + * + * Copyright 2019 Google Inc. + * https://developers.google.com/blockly/ + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +/** + * @fileoverview Generator for unique element IDs. + * For UUIDs use Blockly.utils.genUid. The ID generator should primarily be + * used for IDs that end up in the DOM. + * @author samelh@google.com (Sam El-Husseini) + */ +'use strict'; + + +goog.provide('Blockly.utils.IdGenerator'); + + +/** + * Creates a new id generator. + * @constructor + * @final + */ +Blockly.utils.IdGenerator = function() {}; + +/** + * Get the singleton instance of Blockly.utils.IdGenerator. + * @returns {Blockly.utils.IdGenerator} singleton instance + */ +Blockly.utils.IdGenerator.getInstance = function() { + if (!Blockly.utils.IdGenerator.instance_) { + Blockly.utils.IdGenerator.instance_ = new Blockly.utils.IdGenerator(); + } + return Blockly.utils.IdGenerator.instance_; +}; + +/** + * Next unique ID to use + * @type {number} + * @private + */ +Blockly.utils.IdGenerator.prototype.nextId_ = 0; + +/** + * Gets the next unique ID. + * The difference between this and genUid is that getNextUniqueId generates + * IDs compatible with the HTML4 id attribute restrictions: + * Use only ASCII letters, digits, '_', '-' and '.' + * @return {string} The next unique identifier. + */ +Blockly.utils.IdGenerator.prototype.getNextUniqueId = function() { + return 'blockly:' + (this.nextId_++).toString(36); +};