@blueprintjs/core
Version:
Core styles & components
196 lines • 9.71 kB
JavaScript
/*
* Copyright 2016 Palantir Technologies, Inc. All rights reserved.
*
* 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.
*/
import classNames from "classnames";
import * as React from "react";
import { AbstractPureComponent, Classes, Utils } from "../../common";
import { DISPLAYNAME_PREFIX } from "../../common/props";
import { clamp } from "../../common/utils";
import { formatPercentage } from "./sliderUtils";
// props that require number values, for validation
const NUMBER_PROPS = ["max", "min", "stepSize", "tickSize", "value"];
/** Internal component for a Handle with click/drag/keyboard logic to determine a new value. */
export class Handle extends AbstractPureComponent {
static displayName = `${DISPLAYNAME_PREFIX}.SliderHandle`;
state = {
isMoving: false,
};
handleElement = null;
refHandlers = {
handle: (el) => (this.handleElement = el),
};
componentDidMount() {
// The first time this component renders, it has no ref to the handle and thus incorrectly centers the handle.
// Therefore, on the first mount, force a re-render to center the handle with the ref'd component.
this.forceUpdate();
}
render() {
const { className, disabled, label, min, max, value, vertical, htmlProps } = this.props;
const { isMoving } = this.state;
return (React.createElement("span", { role: "slider", tabIndex: 0, ...htmlProps, className: classNames(Classes.SLIDER_HANDLE, { [Classes.ACTIVE]: isMoving }, className), onKeyDown: disabled ? undefined : this.handleKeyDown, onKeyUp: disabled ? undefined : this.handleKeyUp, onMouseDown: disabled ? undefined : this.beginHandleMovement, onTouchStart: disabled ? undefined : this.beginHandleTouchMovement, ref: this.refHandlers.handle, style: this.getStyleProperties(), "aria-valuemin": min, "aria-valuemax": max, "aria-valuenow": value, "aria-orientation": vertical ? "vertical" : "horizontal" }, label == null ? null : React.createElement("span", { className: Classes.SLIDER_LABEL }, label)));
}
componentWillUnmount() {
this.removeDocumentEventListeners();
}
/** Convert client pixel to value between min and max. */
clientToValue(clientPixel) {
const { stepSize, tickSize, value, vertical } = this.props;
if (this.handleElement == null) {
return value;
}
// #1769: this logic doesn't work perfectly when the tick size is
// smaller than the handle size; it may be off by a tick or two.
const clientPixelNormalized = vertical ? window.innerHeight - clientPixel : clientPixel;
const handleCenterPixel = this.getHandleElementCenterPixel(this.handleElement);
const pixelDelta = clientPixelNormalized - handleCenterPixel;
if (isNaN(pixelDelta)) {
return value;
}
// convert pixels to range value in increments of `stepSize`
return value + Math.round(pixelDelta / (tickSize * stepSize)) * stepSize;
}
mouseEventClientOffset(event) {
return this.props.vertical ? event.clientY : event.clientX;
}
touchEventClientOffset(event) {
const touch = event.changedTouches[0];
return this.props.vertical ? touch.clientY : touch.clientX;
}
beginHandleMovement = (event) => {
document.addEventListener("mousemove", this.handleHandleMovement);
document.addEventListener("mouseup", this.endHandleMovement);
this.setState({ isMoving: true });
this.changeValue(this.clientToValue(this.mouseEventClientOffset(event)));
};
beginHandleTouchMovement = (event) => {
document.addEventListener("touchmove", this.handleHandleTouchMovement);
document.addEventListener("touchend", this.endHandleTouchMovement);
document.addEventListener("touchcancel", this.endHandleTouchMovement);
this.setState({ isMoving: true });
this.changeValue(this.clientToValue(this.touchEventClientOffset(event)));
};
validateProps(props) {
for (const prop of NUMBER_PROPS) {
if (typeof props[prop] !== "number") {
throw new Error(`[Blueprint] <Handle> requires number value for ${prop} prop`);
}
}
}
getStyleProperties = () => {
if (this.handleElement == null) {
return {};
}
// The handle midpoint of RangeSlider is actually shifted by a margin to
// be on the edge of the visible handle element. Because the midpoint
// calculation does not take this margin into account, we instead
// measure the long side (which is equal to the short side plus the
// margin).
const { min = 0, tickSizeRatio, value, vertical } = this.props;
const { handleMidpoint } = this.getHandleMidpointAndOffset(this.handleElement, true);
const offsetRatio = (value - min) * tickSizeRatio;
const offsetCalc = `calc(${formatPercentage(offsetRatio)} - ${handleMidpoint}px)`;
return vertical ? { bottom: offsetCalc } : { left: offsetCalc };
};
endHandleMovement = (event) => {
this.handleMoveEndedAt(this.mouseEventClientOffset(event));
};
endHandleTouchMovement = (event) => {
this.handleMoveEndedAt(this.touchEventClientOffset(event));
};
handleMoveEndedAt = (clientPixel) => {
this.removeDocumentEventListeners();
this.setState({ isMoving: false });
// always invoke onRelease; changeValue may call onChange if value is different
const finalValue = this.changeValue(this.clientToValue(clientPixel));
this.props.onRelease?.(finalValue);
};
handleHandleMovement = (event) => {
this.handleMovedTo(this.mouseEventClientOffset(event));
};
handleHandleTouchMovement = (event) => {
this.handleMovedTo(this.touchEventClientOffset(event));
};
handleMovedTo = (clientPixel) => {
if (this.state.isMoving && !this.props.disabled) {
this.changeValue(this.clientToValue(clientPixel));
}
};
handleKeyDown = (event) => {
const { stepSize, value } = this.props;
const { key } = event;
if (key === "ArrowDown" || key === "ArrowLeft") {
this.changeValue(value - stepSize);
// this key event has been handled! prevent browser scroll on up/down
event.preventDefault();
}
else if (key === "ArrowUp" || key === "ArrowRight") {
this.changeValue(value + stepSize);
event.preventDefault();
}
};
handleKeyUp = (event) => {
if (Utils.isArrowKey(event)) {
this.props.onRelease?.(this.props.value);
}
};
/** Clamp value and invoke callback if it differs from current value */
changeValue(newValue, callback = this.props.onChange) {
newValue = this.clamp(newValue);
if (!isNaN(newValue) && this.props.value !== newValue) {
callback?.(newValue);
}
return newValue;
}
/** Clamp value between min and max props */
clamp(value) {
return clamp(value, this.props.min, this.props.max);
}
getHandleElementCenterPixel(handleElement) {
const { handleMidpoint, handleOffset } = this.getHandleMidpointAndOffset(handleElement);
return handleOffset + handleMidpoint;
}
getHandleMidpointAndOffset(handleElement, useOppositeDimension = false) {
if (handleElement == null) {
return { handleMidpoint: 0, handleOffset: 0 };
}
const { vertical } = this.props;
// N.B. element.clientHeight does not include border size.
// Also, element.getBoundingClientRect() is useful to get the top & left position on the page, but
// it fails to accurately measure element width & height inside absolutely-positioned and CSS-transformed
// containers like Popovers, so we use element.offsetWidth & offsetHeight instead (see https://github.com/palantir/blueprint/issues/4417).
const handleRect = handleElement.getBoundingClientRect();
handleRect.width = handleElement.offsetWidth;
handleRect.height = handleElement.offsetHeight;
const sizeKey = vertical
? useOppositeDimension
? "width"
: "height"
: useOppositeDimension
? "height"
: "width";
// "bottom" value seems to be consistently incorrect, so explicitly
// calculate it using the window offset instead.
const handleOffset = vertical ? window.innerHeight - (handleRect.top + handleRect[sizeKey]) : handleRect.left;
return { handleMidpoint: handleRect[sizeKey] / 2, handleOffset };
}
removeDocumentEventListeners() {
document.removeEventListener("mousemove", this.handleHandleMovement);
document.removeEventListener("mouseup", this.endHandleMovement);
document.removeEventListener("touchmove", this.handleHandleTouchMovement);
document.removeEventListener("touchend", this.endHandleTouchMovement);
document.removeEventListener("touchcancel", this.endHandleTouchMovement);
}
}
//# sourceMappingURL=handle.js.map