Files
blockly/core/drag_target.ts
Maribeth Bottorff 037eb59b89 chore: Lint TsDoc. (#6353)
* chore: add linting for tsdoc

* chore: don't require types on return

* chore: remove redundant fileoverview from ts

* chore: change return to returns and add some newlines

* chore: remove license tag

* chore: don't require params/return docs

* chore: remove spurious struct tags

* Revert "chore: change return to returns and add some newlines"

This reverts commit d6d8656a45.

* chore: don't auto-add param names

* chore: disable require-param bc it breaks on this

* return to returns and add line breaks

* chore: configure additional jsdoc rules

* chore: run format

* Revert "chore: remove license tag"

This reverts commit 173455588a.

* chore: allow license tag format

* chore: only require jsdoc on exported items

* chore: add missing jsdoc or silence where needed

* chore: run format

* chore: lint fixes
2022-08-23 14:27:22 -07:00

98 lines
2.6 KiB
TypeScript

/**
* @license
* Copyright 2021 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
/**
* The abstract class for a component with custom behaviour when a
* block or bubble is dragged over or dropped on top of it.
*
* @class
*/
import * as goog from '../closure/goog/goog.js';
goog.declareModuleId('Blockly.DragTarget');
import type {IDragTarget} from './interfaces/i_drag_target.js';
import type {IDraggable} from './interfaces/i_draggable.js';
import type {Rect} from './utils/rect.js';
/**
* Abstract class for a component with custom behaviour when a block or bubble
* is dragged over or dropped on top of it.
*
* @alias Blockly.DragTarget
*/
export class DragTarget implements IDragTarget {
/**
* The unique id for this component that is used to register with the
* ComponentManager.
*/
// TODO(b/109816955): remove '!', see go/strict-prop-init-fix.
id!: string;
/**
* Constructor for DragTarget. It exists to add the id property and should not
* be called directly, only by a subclass.
*/
constructor() {}
/**
* Handles when a cursor with a block or bubble enters this drag target.
*
* @param _dragElement The block or bubble currently being dragged.
*/
onDragEnter(_dragElement: IDraggable) {}
// no-op
/**
* Handles when a cursor with a block or bubble is dragged over this drag
* target.
*
* @param _dragElement The block or bubble currently being dragged.
*/
onDragOver(_dragElement: IDraggable) {}
// no-op
/**
* Handles when a cursor with a block or bubble exits this drag target.
*
* @param _dragElement The block or bubble currently being dragged.
*/
onDragExit(_dragElement: IDraggable) {}
// no-op
/**
* Handles when a block or bubble is dropped on this component.
* Should not handle delete here.
*
* @param _dragElement The block or bubble currently being dragged.
*/
onDrop(_dragElement: IDraggable) {}
// no-op
/**
* Returns the bounding rectangle of the drag target area in pixel units
* relative to the Blockly injection div.
*
* @returns The component's bounding box. Null if drag target area should be
* ignored.
*/
getClientRect(): Rect|null {
return null;
}
/**
* Returns whether the provided block or bubble should not be moved after
* being dropped on this component. If true, the element will return to where
* it was when the drag started.
*
* @param _dragElement The block or bubble currently being dragged.
* @returns Whether the block or bubble provided should be returned to drag
* start.
*/
shouldPreventMove(_dragElement: IDraggable): boolean {
return false;
}
}