Files
blockly/core/delete_area.js
Aaron Dodson 3851b14627 refactor: Migrate to named exports (#5623)
* refactor: Migrate to named exports

* fix: Sort requires

* fix: Remove duplicate deps
2021-10-20 15:53:23 -07:00

85 lines
2.5 KiB
JavaScript

/**
* @license
* Copyright 2021 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @fileoverview The abstract class for a component that can delete a block or
* bubble that is dropped on top of it.
*/
'use strict';
/**
* The abstract class for a component that can delete a block or
* bubble that is dropped on top of it.
* @class
*/
goog.module('Blockly.DeleteArea');
const object = goog.require('Blockly.utils.object');
const {BlockSvg} = goog.require('Blockly.BlockSvg');
const {DragTarget} = goog.require('Blockly.DragTarget');
/* eslint-disable-next-line no-unused-vars */
const {IDeleteArea} = goog.require('Blockly.IDeleteArea');
/* eslint-disable-next-line no-unused-vars */
const {IDraggable} = goog.requireType('Blockly.IDraggable');
/**
* Abstract class for a component that can delete a block or bubble that is
* dropped on top of it.
* @extends {DragTarget}
* @implements {IDeleteArea}
* @constructor
* @alias Blockly.DeleteArea
*/
const DeleteArea = function() {
DeleteArea.superClass_.constructor.call(this);
/**
* Whether the last block or bubble dragged over this delete area would be
* deleted if dropped on this component.
* This property is not updated after the block or bubble is deleted.
* @type {boolean}
* @protected
*/
this.wouldDelete_ = false;
};
object.inherits(DeleteArea, DragTarget);
/**
* Returns whether the provided block or bubble would be deleted if dropped on
* this area.
* This method should check if the element is deletable and is always called
* before onDragEnter/onDragOver/onDragExit.
* @param {!IDraggable} element The block or bubble currently being
* dragged.
* @param {boolean} couldConnect Whether the element could could connect to
* another.
* @return {boolean} Whether the element provided would be deleted if dropped on
* this area.
*/
DeleteArea.prototype.wouldDelete = function(element, couldConnect) {
if (element instanceof BlockSvg) {
const block = /** @type {BlockSvg} */ (element);
const couldDeleteBlock = !block.getParent() && block.isDeletable();
this.updateWouldDelete_(couldDeleteBlock && !couldConnect);
} else {
this.updateWouldDelete_(element.isDeletable());
}
return this.wouldDelete_;
};
/**
* Updates the internal wouldDelete_ state.
* @param {boolean} wouldDelete The new value for the wouldDelete state.
* @protected
*/
DeleteArea.prototype.updateWouldDelete_ = function(wouldDelete) {
this.wouldDelete_ = wouldDelete;
};
exports.DeleteArea = DeleteArea;