mirror of
https://github.com/google/blockly.git
synced 2026-01-07 17:10:11 +01:00
117 lines
3.2 KiB
JavaScript
117 lines
3.2 KiB
JavaScript
/**
|
|
* @license
|
|
* Copyright 2017 Google LLC
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*/
|
|
|
|
/**
|
|
* @fileoverview Methods for dragging a workspace visually.
|
|
*/
|
|
'use strict';
|
|
|
|
/**
|
|
* Methods for dragging a workspace visually.
|
|
* @class
|
|
*/
|
|
goog.module('Blockly.WorkspaceDragger');
|
|
|
|
const common = goog.require('Blockly.common');
|
|
const {Coordinate} = goog.require('Blockly.utils.Coordinate');
|
|
/* eslint-disable-next-line no-unused-vars */
|
|
const {WorkspaceSvg} = goog.requireType('Blockly.WorkspaceSvg');
|
|
|
|
|
|
/**
|
|
* Class for a workspace dragger. It moves the workspace around when it is
|
|
* being dragged by a mouse or touch.
|
|
* Note that the workspace itself manages whether or not it has a drag surface
|
|
* and how to do translations based on that. This simply passes the right
|
|
* commands based on events.
|
|
* @param {!WorkspaceSvg} workspace The workspace to drag.
|
|
* @constructor
|
|
* @alias Blockly.WorkspaceDragger
|
|
*/
|
|
const WorkspaceDragger = function(workspace) {
|
|
/**
|
|
* @type {!WorkspaceSvg}
|
|
* @private
|
|
*/
|
|
this.workspace_ = workspace;
|
|
|
|
/**
|
|
* Whether horizontal scroll is enabled.
|
|
* @type {boolean}
|
|
* @private
|
|
*/
|
|
this.horizontalScrollEnabled_ = this.workspace_.isMovableHorizontally();
|
|
|
|
/**
|
|
* Whether vertical scroll is enabled.
|
|
* @type {boolean}
|
|
* @private
|
|
*/
|
|
this.verticalScrollEnabled_ = this.workspace_.isMovableVertically();
|
|
|
|
/**
|
|
* The scroll position of the workspace at the beginning of the drag.
|
|
* Coordinate system: pixel coordinates.
|
|
* @type {!Coordinate}
|
|
* @protected
|
|
*/
|
|
this.startScrollXY_ = new Coordinate(workspace.scrollX, workspace.scrollY);
|
|
};
|
|
|
|
/**
|
|
* Sever all links from this object.
|
|
* @package
|
|
* @suppress {checkTypes}
|
|
*/
|
|
WorkspaceDragger.prototype.dispose = function() {
|
|
this.workspace_ = null;
|
|
};
|
|
|
|
/**
|
|
* Start dragging the workspace.
|
|
* @package
|
|
*/
|
|
WorkspaceDragger.prototype.startDrag = function() {
|
|
if (common.getSelected()) {
|
|
common.getSelected().unselect();
|
|
}
|
|
this.workspace_.setupDragSurface();
|
|
};
|
|
|
|
/**
|
|
* Finish dragging the workspace and put everything back where it belongs.
|
|
* @param {!Coordinate} currentDragDeltaXY How far the pointer has
|
|
* moved from the position at the start of the drag, in pixel coordinates.
|
|
* @package
|
|
*/
|
|
WorkspaceDragger.prototype.endDrag = function(currentDragDeltaXY) {
|
|
// Make sure everything is up to date.
|
|
this.drag(currentDragDeltaXY);
|
|
this.workspace_.resetDragSurface();
|
|
};
|
|
|
|
/**
|
|
* Move the workspace based on the most recent mouse movements.
|
|
* @param {!Coordinate} currentDragDeltaXY How far the pointer has
|
|
* moved from the position at the start of the drag, in pixel coordinates.
|
|
* @package
|
|
*/
|
|
WorkspaceDragger.prototype.drag = function(currentDragDeltaXY) {
|
|
const newXY = Coordinate.sum(this.startScrollXY_, currentDragDeltaXY);
|
|
|
|
if (this.horizontalScrollEnabled_ && this.verticalScrollEnabled_) {
|
|
this.workspace_.scroll(newXY.x, newXY.y);
|
|
} else if (this.horizontalScrollEnabled_) {
|
|
this.workspace_.scroll(newXY.x, this.workspace_.scrollY);
|
|
} else if (this.verticalScrollEnabled_) {
|
|
this.workspace_.scroll(this.workspace_.scrollX, newXY.y);
|
|
} else {
|
|
throw new TypeError('Invalid state.');
|
|
}
|
|
};
|
|
|
|
exports.WorkspaceDragger = WorkspaceDragger;
|