mirror of
https://github.com/google/blockly.git
synced 2026-01-10 10:27:08 +01:00
a47bd93f4c
Adding support for extensions, functions that can assist with loading blocks, much like init functions, but that can be referenced from JSON definitions. This allows JSON definitions to define dynamic blocks such as onchange handlers and mutators. Rewrote math_number as an example pure JSON block.
76 lines
2.6 KiB
JavaScript
76 lines
2.6 KiB
JavaScript
/**
|
|
* @license
|
|
* Visual Blocks Editor
|
|
*
|
|
* Copyright 2017 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 Extensions are functions that help initialize blocks, usually
|
|
* adding dynamic behavior such as onchange handlers and mutators. These
|
|
* are applied using Block.applyExtension(), or the JSON "extensions"
|
|
* array attribute.
|
|
* @author Anm@anm.me (Andrew n marshall)
|
|
*/
|
|
'use strict';
|
|
|
|
goog.provide('Blockly.Extensions');
|
|
|
|
|
|
/**
|
|
* The set of all registered extensions, keyed by extension name/id.
|
|
* @private
|
|
*/
|
|
Blockly.Extensions.ALL_ = {};
|
|
|
|
/**
|
|
* Registers a new extension function. Extensions are functions that help
|
|
* initialize blocks, usually adding dynamic behavior such as onchange
|
|
* handlers and mutators. These are applied using Block.applyExtension(), or
|
|
* the JSON "extensions" array attribute.
|
|
* @param {string} name The name of this extension.
|
|
* @param {function} initFn The function to initialize an extended block.
|
|
* @throws {Error} if the extension name is empty, the extension is already
|
|
* registered, or extensionFn is not a function.
|
|
*/
|
|
Blockly.Extensions.register = function(name, initFn) {
|
|
if (!goog.isString(name) || goog.string.isEmptyOrWhitespace(name)) {
|
|
throw new Error('Error: Invalid extension name "' + name + '"');
|
|
}
|
|
if (Blockly.Extensions.ALL_[name]) {
|
|
throw new Error('Error: Extension "' + name + '" is already registered.');
|
|
}
|
|
if (!goog.isFunction(initFn)) {
|
|
throw new Error('Error: Extension "' + name + '" must be a function');
|
|
}
|
|
Blockly.Extensions.ALL_[name] = initFn;
|
|
};
|
|
|
|
/**
|
|
* Applies an extension method to a block. This should only be called during
|
|
* block construction.
|
|
* @param {string} name The name of the extension.
|
|
* @param {!Blockly.Block} block The block to apply the named extension to.
|
|
* @throws {Error} if the extension is not found.
|
|
*/
|
|
Blockly.Extensions.apply = function(name, block) {
|
|
var extensionFn = Blockly.Extensions.ALL_[name];
|
|
if (!goog.isFunction(extensionFn)) {
|
|
throw new Error('Error: Extension "' + name + '" not found.');
|
|
}
|
|
extensionFn.apply(block);
|
|
};
|