Files
openlayers/src/ol/interaction/KeyboardPan.js
2022-02-14 21:53:07 +01:00

126 lines
4.0 KiB
JavaScript

/**
* @module ol/interaction/KeyboardPan
*/
import EventType from '../events/EventType.js';
import Interaction, {pan} from './Interaction.js';
import KeyCode from '../events/KeyCode.js';
import {noModifierKeys, targetNotEditable} from '../events/condition.js';
import {rotate as rotateCoordinate} from '../coordinate.js';
/**
* @typedef {Object} Options
* @property {import("../events/condition.js").Condition} [condition] A function that
* takes an {@link module:ol/MapBrowserEvent~MapBrowserEvent} and returns a
* boolean to indicate whether that event should be handled. Default is
* {@link module:ol/events/condition.noModifierKeys} and
* {@link module:ol/events/condition.targetNotEditable}.
* @property {number} [duration=100] Animation duration in milliseconds.
* @property {number} [pixelDelta=128] The amount of pixels to pan on each key
* press.
*/
/**
* @classdesc
* Allows the user to pan the map using keyboard arrows.
* Note that, although this interaction is by default included in maps,
* the keys can only be used when browser focus is on the element to which
* the keyboard events are attached. By default, this is the map div,
* though you can change this with the `keyboardEventTarget` in
* {@link module:ol/Map~Map}. `document` never loses focus but, for any other
* element, focus will have to be on, and returned to, this element if the keys
* are to function.
* See also {@link module:ol/interaction/KeyboardZoom~KeyboardZoom}.
* @api
*/
class KeyboardPan extends Interaction {
/**
* @param {Options} [opt_options] Options.
*/
constructor(opt_options) {
super();
const options = opt_options || {};
/**
* @private
* @param {import("../MapBrowserEvent.js").default} mapBrowserEvent Browser event.
* @return {boolean} Combined condition result.
*/
this.defaultCondition_ = function (mapBrowserEvent) {
return (
noModifierKeys(mapBrowserEvent) && targetNotEditable(mapBrowserEvent)
);
};
/**
* @private
* @type {import("../events/condition.js").Condition}
*/
this.condition_ =
options.condition !== undefined
? options.condition
: this.defaultCondition_;
/**
* @private
* @type {number}
*/
this.duration_ = options.duration !== undefined ? options.duration : 100;
/**
* @private
* @type {number}
*/
this.pixelDelta_ =
options.pixelDelta !== undefined ? options.pixelDelta : 128;
}
/**
* Handles the {@link module:ol/MapBrowserEvent~MapBrowserEvent map browser event} if it was a
* `KeyEvent`, and decides the direction to pan to (if an arrow key was
* pressed).
* @param {import("../MapBrowserEvent.js").default} mapBrowserEvent Map browser event.
* @return {boolean} `false` to stop event propagation.
* @this {KeyboardPan}
*/
handleEvent(mapBrowserEvent) {
let stopEvent = false;
if (mapBrowserEvent.type == EventType.KEYDOWN) {
const keyEvent = /** @type {KeyboardEvent} */ (
mapBrowserEvent.originalEvent
);
const keyCode = keyEvent.keyCode;
if (
this.condition_(mapBrowserEvent) &&
(keyCode == KeyCode.DOWN ||
keyCode == KeyCode.LEFT ||
keyCode == KeyCode.RIGHT ||
keyCode == KeyCode.UP)
) {
const map = mapBrowserEvent.map;
const view = map.getView();
const mapUnitsDelta = view.getResolution() * this.pixelDelta_;
let deltaX = 0,
deltaY = 0;
if (keyCode == KeyCode.DOWN) {
deltaY = -mapUnitsDelta;
} else if (keyCode == KeyCode.LEFT) {
deltaX = -mapUnitsDelta;
} else if (keyCode == KeyCode.RIGHT) {
deltaX = mapUnitsDelta;
} else {
deltaY = mapUnitsDelta;
}
const delta = [deltaX, deltaY];
rotateCoordinate(delta, view.getRotation());
pan(view, delta, this.duration_);
keyEvent.preventDefault();
stopEvent = true;
}
}
return !stopEvent;
}
}
export default KeyboardPan;