Files
mkdocs-material/src/assets/javascripts/utilities/hidden/index.ts

67 lines
2.1 KiB
TypeScript

/*
* Copyright (c) 2016-2019 Martin Donath <martin.donath@squidfunk.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
import { OperatorFunction, animationFrameScheduler, pipe } from "rxjs"
import {
distinctUntilChanged,
finalize,
map,
observeOn,
tap
} from "rxjs/operators"
import { resetHidden, setHidden } from "actions"
import { ViewportOffset } from "../agent"
/* ----------------------------------------------------------------------------
* Functions
* ------------------------------------------------------------------------- */
/**
* Paint hideable from source observable
*
* @param el - Hideable element
* @param offset - Additional offset
*
* @return Operator function
*/
export function paintHidden(
el: HTMLElement, offset: number = 0
): OperatorFunction<ViewportOffset, boolean> {
return pipe(
map(({ y }) => y >= offset),
distinctUntilChanged(),
/* Defer repaint to next animation frame */
observeOn(animationFrameScheduler),
tap(value => {
setHidden(el, value)
}),
/* Reset on complete or error */
finalize(() => {
resetHidden(el)
})
)
}