element-portable/src/NodeAnimator.tsx
Michael Telatynski 4f14d3f5ae
Stash
Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>
2024-12-06 11:41:40 +00:00

130 lines
4.7 KiB
TypeScript

/*
Copyright 2024 New Vector Ltd.
Copyright 2022 The Matrix.org Foundation C.I.C.
SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only
Please see LICENSE files in the repository root for full details.
*/
import React, { HTMLAttributes, Key, MutableRefObject, ReactElement, RefCallback } from "react";
interface IChildProps {
style: React.CSSProperties;
ref: RefCallback<HTMLElement>;
}
interface IProps {
// either a list of child nodes, or a single child.
children: React.ReactNode;
// a list of state objects to apply to each child node in turn
startStyles: React.CSSProperties[];
innerRef?: MutableRefObject<any>;
}
function isReactElement(c: ReturnType<(typeof React.Children)["toArray"]>[number]): c is ReactElement<any> {
return typeof c === "object" && "type" in c;
}
/**
* The NodeAnimator contains components and animates transitions.
* It will only pick up direct changes to properties ('left', currently), and so
* will not work for animating positional changes where the position is implicit
* from DOM order. This makes it a lot simpler and lighter: if you need fully
* automatic positional animation, look at react-shuffle or similar libraries.
*/
export default class NodeAnimator extends React.Component<IProps> {
private nodes: Record<string, HTMLElement> = {};
private children: { [key: string]: ReactElement<any> } = {};
public static defaultProps: Partial<IProps> = {
startStyles: [],
};
public constructor(props: IProps) {
super(props);
this.updateChildren(this.props.children);
}
public componentDidUpdate(): void {
this.updateChildren(this.props.children);
}
/**
*
* @param {HTMLElement} node element to apply styles to
* @param {React.CSSProperties} styles a key/value pair of CSS properties
* @returns {void}
*/
private applyStyles(node: HTMLElement, styles: React.CSSProperties): void {
Object.entries(styles).forEach(([property, value]) => {
node.style[property as keyof Omit<CSSStyleDeclaration, "length" | "parentRule">] = value;
});
}
private updateChildren(newChildren: React.ReactNode): void {
const oldChildren = this.children || {};
this.children = {};
React.Children.toArray(newChildren).forEach((c) => {
if (!isReactElement(c)) return;
const props = c.props as HTMLAttributes<HTMLElement>;
if (oldChildren[c.key!]) {
const old = oldChildren[c.key!];
const oldNode = this.nodes[old.key!];
if (oldNode && oldNode.style.left !== props.style!.left) {
this.applyStyles(oldNode, { left: props.style!.left });
}
// clone the old element with the props (and children) of the new element
// so prop updates are still received by the children.
this.children[c.key!] = React.cloneElement(old, props, props.children);
} else {
// new element. If we have a startStyle, use that as the style and go through
// the enter animations
const newProps: Partial<IChildProps> = {};
const restingStyle = props.style!;
const startStyles = this.props.startStyles;
if (startStyles.length > 0) {
const startStyle = startStyles[0];
newProps.style = startStyle;
}
newProps.ref = (n) => this.collectNode(c.key!, n, restingStyle);
this.children[c.key!] = React.cloneElement(c, newProps);
}
});
}
private collectNode(k: Key, domNode: HTMLElement | null, restingStyle: React.CSSProperties): void {
const key = typeof k === "bigint" ? Number(k) : k;
if (domNode && this.nodes[key] === undefined && this.props.startStyles.length > 0) {
const startStyles = this.props.startStyles;
// start from startStyle 1: 0 is the one we gave it
// to start with, so now we animate 1 etc.
for (let i = 1; i < startStyles.length; ++i) {
this.applyStyles(domNode, startStyles[i]);
}
// and then we animate to the resting state
window.setTimeout(() => {
this.applyStyles(domNode, restingStyle);
}, 0);
}
if (domNode) {
this.nodes[key] = domNode;
} else {
delete this.nodes[key];
}
if (this.props.innerRef) {
this.props.innerRef.current = domNode;
}
}
public render(): React.ReactNode {
return <>{Object.values(this.children)}</>;
}
}