Vmeda.Online/src/core/directives/collapsible-item.ts

309 lines
10 KiB
TypeScript

// (C) Copyright 2015 Moodle Pty Ltd.
//
// 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 { Directive, ElementRef, Input, OnDestroy, OnInit } from '@angular/core';
import { CoreCancellablePromise } from '@classes/cancellable-promise';
import { CoreLoadingComponent } from '@components/loading/loading';
import { CoreSettingsHelper } from '@features/settings/services/settings-helper';
import { CoreUtils } from '@services/utils/utils';
import { Translate } from '@singletons';
import { CoreColors } from '@singletons/colors';
import { CoreDirectivesRegistry } from '@singletons/directives-registry';
import { CoreDom } from '@singletons/dom';
import { CoreEventObserver } from '@singletons/events';
import { Subscription } from 'rxjs';
import { CoreFormatTextDirective } from './format-text';
const defaultMaxHeight = 80;
const minMaxHeight = 56;
/**
* Directive to make an element collapsible.
*
* Example usage:
*
* <div collapsible-item>
*/
@Directive({
selector: '[collapsible-item]',
})
export class CoreCollapsibleItemDirective implements OnInit, OnDestroy {
/**
* Max height in pixels to render the content box. It should be 56 at least to make sense.
* Using this parameter will force display: block to calculate height better.
* If you want to avoid this use class="inline" at the same time to use display: inline-block.
*/
@Input('collapsible-item') height: number | string = defaultMaxHeight;
protected element: HTMLElement;
protected toggleExpandEnabled = false;
protected expanded = false;
protected maxHeight = defaultMaxHeight;
protected expandedHeight = 0;
protected resizeListener?: CoreEventObserver;
protected darkModeListener?: Subscription;
protected domPromise?: CoreCancellablePromise<void>;
protected visiblePromise?: CoreCancellablePromise<void>;
protected uniqueId: string;
protected loadingHeight = false;
protected pageDidEnterListener?: EventListener;
protected page?: HTMLElement;
constructor(el: ElementRef<HTMLElement>) {
this.element = el.nativeElement;
this.element.addEventListener('click', (event) => this.elementClicked(event));
this.uniqueId = 'collapsible-item-' + CoreUtils.getUniqueId('CoreCollapsibleItemDirective');
this.element.id = this.uniqueId;
}
/**
* @inheritdoc
*/
async ngOnInit(): Promise<void> {
if (this.height === null) {
return;
}
if (typeof this.height === 'string') {
this.maxHeight = this.height === ''
? defaultMaxHeight
: parseInt(this.height, 10);
} else {
this.maxHeight = this.height;
}
this.maxHeight = this.maxHeight < minMaxHeight ? defaultMaxHeight : this.maxHeight;
if (!this.maxHeight) {
// Do not collapse.
return;
}
this.element.classList.add('collapsible-item');
await this.waitLoadingsDone();
await this.calculateHeight();
this.page?.addEventListener(
'ionViewDidEnter',
this.pageDidEnterListener = () => {
this.calculateHeight();
},
);
this.resizeListener = CoreDom.onWindowResize(() => {
this.calculateHeight();
}, 50);
this.darkModeListener = CoreSettingsHelper.onDarkModeChange().subscribe(() => {
this.setGradientColor();
});
}
/**
* Wait until all <core-loading> children inside the page.
*
* @returns Promise resolved when loadings are done.
*/
protected async waitLoadingsDone(): Promise<void> {
this.domPromise = CoreDom.waitToBeInDOM(this.element);
await this.domPromise;
this.page = this.element.closest<HTMLElement>('.ion-page') || undefined;
if (!this.page) {
return;
}
await CoreDirectivesRegistry.waitDirectivesReady(this.page, 'core-loading', CoreLoadingComponent);
}
/**
* Wait until all <core-format-text> children inside the element are done rendering.
*/
protected async waitFormatTextsRendered(): Promise<void> {
await CoreDirectivesRegistry.waitDirectivesReady(this.element, 'core-format-text', CoreFormatTextDirective);
}
/**
* Calculate the height and check if we need to display show more or not.
*/
protected async calculateHeight(): Promise<void> {
if (this.loadingHeight) {
// Already calculating, return.
return;
}
this.loadingHeight = true;
this.visiblePromise = CoreDom.waitToBeVisible(this.element);
await this.visiblePromise;
// Remove max-height (if any) to calculate the real height.
this.element.classList.add('collapsible-loading-height');
await this.waitFormatTextsRendered();
this.expandedHeight = this.element.getBoundingClientRect().height;
// Restore the max height now.
this.element.classList.remove('collapsible-loading-height');
// If cannot calculate height, shorten always.
const enable = !this.expandedHeight || this.expandedHeight >= this.maxHeight;
this.setExpandButtonEnabled(enable);
this.setGradientColor();
this.loadingHeight = false;
}
/**
* Sets the gradient color based on the background.
*/
protected setGradientColor(): void {
if (!this.toggleExpandEnabled) {
return;
}
let coloredElement: HTMLElement | null = this.element;
let backgroundColor = [0, 0, 0, 0];
let background = '';
while (coloredElement && backgroundColor[3] === 0) {
background = getComputedStyle(coloredElement).backgroundColor;
backgroundColor = CoreColors.getColorRGBA(background);
coloredElement = coloredElement.parentElement;
}
if (backgroundColor[3] !== 0) {
delete(backgroundColor[3]);
const bgList = backgroundColor.join(',');
this.element.style.setProperty('--background-gradient-rgb', `${bgList}`);
}
}
/**
* Sets if expand button is enabled or not.
*
* @param enable Wether enable or disable.
*/
protected setExpandButtonEnabled(enable: boolean): void {
this.toggleExpandEnabled = enable;
this.element.classList.toggle('collapsible-enabled', enable);
if (!enable || this.element.querySelector('ion-button.collapsible-toggle')) {
this.setHeight(!enable || this.expanded ? undefined : this.maxHeight);
return;
}
// Add expand/collapse buttons
const toggleButton = document.createElement('ion-button');
toggleButton.classList.add('collapsible-toggle');
toggleButton.setAttribute('fill', 'clear');
toggleButton.setAttribute('aria-controls', this.uniqueId);
const toggleText = document.createElement('span');
toggleText.classList.add('collapsible-toggle-text');
toggleText.classList.add('sr-only');
toggleButton.appendChild(toggleText);
const expandArrow = document.createElement('span');
expandArrow.classList.add('collapsible-toggle-arrow');
toggleButton.appendChild(expandArrow);
this.element.append(toggleButton);
this.toggleExpand(this.expanded);
}
/**
* Set max height to element.
*
* @param height Max height if collapsed or undefined if expanded.
*/
protected setHeight(height?: number): void {
if (height) {
this.element.style.setProperty('--collapsible-height', height + 'px');
} else if (this.expandedHeight) {
this.element.style.setProperty('--collapsible-height', this.expandedHeight + 'px');
} else {
this.element.style.removeProperty('--collapsible-height');
}
}
/**
* Expand or collapse text.
*
* @param expand Wether expand or collapse text. If undefined, will toggle.
*/
protected toggleExpand(expand?: boolean): void {
if (expand === undefined) {
expand = !this.expanded;
}
this.expanded = expand;
// Reset scroll inside the element to show always the top part.
this.element.scrollTo(0, 0);
this.element.classList.toggle('collapsible-collapsed', !expand);
this.setHeight(!expand ? this.maxHeight: undefined);
const toggleButton = this.element.querySelector('ion-button.collapsible-toggle');
const toggleText = toggleButton?.querySelector('.collapsible-toggle-text');
if (!toggleButton || !toggleText) {
return;
}
toggleText.innerHTML = expand ? Translate.instant('core.showless') : Translate.instant('core.showmore');
toggleButton.setAttribute('aria-expanded', expand ? 'true' : 'false');
}
/**
* Listener to call when the element is clicked.
*
* @param e Click event.
*/
elementClicked(e: MouseEvent): void {
if (e.defaultPrevented) {
// Ignore it if the event was prevented by some other listener.
return;
}
if (!this.toggleExpandEnabled) {
// Nothing to do on click, just stop.
return;
}
e.preventDefault();
e.stopPropagation();
this.toggleExpand();
}
/**
* @inheritdoc
*/
ngOnDestroy(): void {
this.resizeListener?.off();
this.darkModeListener?.unsubscribe();
this.domPromise?.cancel();
this.visiblePromise?.cancel();
if (this.page && this.pageDidEnterListener) {
this.page.removeEventListener('ionViewDidEnter', this.pageDidEnterListener);
}
}
}