scratch-blocks/core/field_variable_getter.js

/**
 * @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 Variable getter field.  Appears as a label but has a variable
 *     picker in the right-click menu.
 * @author fenichel@google.com (Rachel Fenichel)
 */
'use strict';

goog.provide('Blockly.FieldVariableGetter');

goog.require('Blockly.Field');


/**
 * Class for a variable getter field.
 * @param {string} text The initial content of the field.
 * @param {string} name Optional CSS class for the field's text.
 * @extends {Blockly.FieldLabel}
 * @constructor
 *
 */
Blockly.FieldVariableGetter = function(text, name) {
  Blockly.FieldVariableGetter.superClass_.constructor.call(this, text);
  this.name_ = name;
};
goog.inherits(Blockly.FieldVariableGetter, Blockly.Field);

/**
 * Editable fields usually show some sort of UI for the user to change them.
 * This field should be serialized, but only edited programmatically.
 * @type {boolean}
 * @public
 */
Blockly.FieldVariableGetter.prototype.EDITABLE = false;

/**
 * Serializable fields are saved by the XML renderer, non-serializable fields
 * are not.  This field should be serialized, but only edited programmatically.
 * @type {boolean}
 * @public
 */
Blockly.FieldVariableGetter.prototype.SERIALIZABLE = true;

/**
 * Install this field on a block.
 */
Blockly.FieldVariableGetter.prototype.init = function() {
  if (this.fieldGroup_) {
    // Field has already been initialized once.
    return;
  }
  Blockly.FieldVariableGetter.superClass_.init.call(this);
  if (!this.getValue()) {
    // Variables without names get uniquely named for this workspace.
    var workspace =
        this.sourceBlock_.isInFlyout ?
            this.sourceBlock_.workspace.targetWorkspace :
            this.sourceBlock_.workspace;
    this.setValue(Blockly.Variables.generateUniqueName(workspace));
  }
  // If the selected variable doesn't exist yet, create it.
  // For instance, some blocks in the toolbox have variable dropdowns filled
  // in by default.
  if (!this.sourceBlock_.isInFlyout) {
    this.sourceBlock_.workspace.createVariable(this.getValue());
  }
};

/**
 * This field is editable, but only through the right-click menu.
 * @private
 */
Blockly.FieldVariableGetter.prototype.showEditor_ = function() {
  // nop.
};

/**
 * Add or remove the UI indicating if this field is editable or not.
 * This field is editable, but only through the right-click menu.
 * Suppress default editable behaviour.
 */
Blockly.FieldVariableGetter.prototype.updateEditable = function() {
  // nop.
};