@angular/cdk
Version:
Angular Material Component Development Kit
1,054 lines (1,047 loc) • 74.5 kB
JavaScript
import * as i0 from '@angular/core';
import { InjectionToken, forwardRef, Directive, Input, inject, NgZone, RendererFactory2, Injectable, ElementRef, Renderer2, ChangeDetectorRef, Injector, afterNextRender, booleanAttribute, Optional, Inject, Component, ViewEncapsulation, ChangeDetectionStrategy, Output, ViewChild, ViewContainerRef, TemplateRef, IterableDiffers, NgModule } from '@angular/core';
import { Subject, of, Observable, Subscription, animationFrameScheduler, asapScheduler, isObservable } from 'rxjs';
import { distinctUntilChanged, auditTime, filter, startWith, takeUntil, pairwise, switchMap, shareReplay } from 'rxjs/operators';
import { a as coerceNumberProperty, c as coerceElement } from './element-15999318.mjs';
import { P as Platform } from './platform-20fc4de8.mjs';
import { D as Directionality } from './directionality-9d44e426.mjs';
import { g as getRtlScrollAxisType, R as RtlScrollAxisType, s as supportsScrollBehavior } from './scrolling-59340c46.mjs';
import { DOCUMENT } from '@angular/common';
import { b as _VIEW_REPEATER_STRATEGY, A as ArrayDataSource, _ as _RecycleViewRepeaterStrategy } from './recycle-view-repeater-strategy-0f32b0a8.mjs';
import { i as isDataSource } from './data-source-d79c6e09.mjs';
import { B as BidiModule } from './bidi-module-04c03e58.mjs';
/** The injection token used to specify the virtual scrolling strategy. */
const VIRTUAL_SCROLL_STRATEGY = new InjectionToken('VIRTUAL_SCROLL_STRATEGY');
/** Virtual scrolling strategy for lists with items of known fixed size. */
class FixedSizeVirtualScrollStrategy {
_scrolledIndexChange = new Subject();
/** @docs-private Implemented as part of VirtualScrollStrategy. */
scrolledIndexChange = this._scrolledIndexChange.pipe(distinctUntilChanged());
/** The attached viewport. */
_viewport = null;
/** The size of the items in the virtually scrolling list. */
_itemSize;
/** The minimum amount of buffer rendered beyond the viewport (in pixels). */
_minBufferPx;
/** The number of buffer items to render beyond the edge of the viewport (in pixels). */
_maxBufferPx;
/**
* @param itemSize The size of the items in the virtually scrolling list.
* @param minBufferPx The minimum amount of buffer (in pixels) before needing to render more
* @param maxBufferPx The amount of buffer (in pixels) to render when rendering more.
*/
constructor(itemSize, minBufferPx, maxBufferPx) {
this._itemSize = itemSize;
this._minBufferPx = minBufferPx;
this._maxBufferPx = maxBufferPx;
}
/**
* Attaches this scroll strategy to a viewport.
* @param viewport The viewport to attach this strategy to.
*/
attach(viewport) {
this._viewport = viewport;
this._updateTotalContentSize();
this._updateRenderedRange();
}
/** Detaches this scroll strategy from the currently attached viewport. */
detach() {
this._scrolledIndexChange.complete();
this._viewport = null;
}
/**
* Update the item size and buffer size.
* @param itemSize The size of the items in the virtually scrolling list.
* @param minBufferPx The minimum amount of buffer (in pixels) before needing to render more
* @param maxBufferPx The amount of buffer (in pixels) to render when rendering more.
*/
updateItemAndBufferSize(itemSize, minBufferPx, maxBufferPx) {
if (maxBufferPx < minBufferPx && (typeof ngDevMode === 'undefined' || ngDevMode)) {
throw Error('CDK virtual scroll: maxBufferPx must be greater than or equal to minBufferPx');
}
this._itemSize = itemSize;
this._minBufferPx = minBufferPx;
this._maxBufferPx = maxBufferPx;
this._updateTotalContentSize();
this._updateRenderedRange();
}
/** @docs-private Implemented as part of VirtualScrollStrategy. */
onContentScrolled() {
this._updateRenderedRange();
}
/** @docs-private Implemented as part of VirtualScrollStrategy. */
onDataLengthChanged() {
this._updateTotalContentSize();
this._updateRenderedRange();
}
/** @docs-private Implemented as part of VirtualScrollStrategy. */
onContentRendered() {
/* no-op */
}
/** @docs-private Implemented as part of VirtualScrollStrategy. */
onRenderedOffsetChanged() {
/* no-op */
}
/**
* Scroll to the offset for the given index.
* @param index The index of the element to scroll to.
* @param behavior The ScrollBehavior to use when scrolling.
*/
scrollToIndex(index, behavior) {
if (this._viewport) {
this._viewport.scrollToOffset(index * this._itemSize, behavior);
}
}
/** Update the viewport's total content size. */
_updateTotalContentSize() {
if (!this._viewport) {
return;
}
this._viewport.setTotalContentSize(this._viewport.getDataLength() * this._itemSize);
}
/** Update the viewport's rendered range. */
_updateRenderedRange() {
if (!this._viewport) {
return;
}
const renderedRange = this._viewport.getRenderedRange();
const newRange = { start: renderedRange.start, end: renderedRange.end };
const viewportSize = this._viewport.getViewportSize();
const dataLength = this._viewport.getDataLength();
let scrollOffset = this._viewport.measureScrollOffset();
// Prevent NaN as result when dividing by zero.
let firstVisibleIndex = this._itemSize > 0 ? scrollOffset / this._itemSize : 0;
// If user scrolls to the bottom of the list and data changes to a smaller list
if (newRange.end > dataLength) {
// We have to recalculate the first visible index based on new data length and viewport size.
const maxVisibleItems = Math.ceil(viewportSize / this._itemSize);
const newVisibleIndex = Math.max(0, Math.min(firstVisibleIndex, dataLength - maxVisibleItems));
// If first visible index changed we must update scroll offset to handle start/end buffers
// Current range must also be adjusted to cover the new position (bottom of new list).
if (firstVisibleIndex != newVisibleIndex) {
firstVisibleIndex = newVisibleIndex;
scrollOffset = newVisibleIndex * this._itemSize;
newRange.start = Math.floor(firstVisibleIndex);
}
newRange.end = Math.max(0, Math.min(dataLength, newRange.start + maxVisibleItems));
}
const startBuffer = scrollOffset - newRange.start * this._itemSize;
if (startBuffer < this._minBufferPx && newRange.start != 0) {
const expandStart = Math.ceil((this._maxBufferPx - startBuffer) / this._itemSize);
newRange.start = Math.max(0, newRange.start - expandStart);
newRange.end = Math.min(dataLength, Math.ceil(firstVisibleIndex + (viewportSize + this._minBufferPx) / this._itemSize));
}
else {
const endBuffer = newRange.end * this._itemSize - (scrollOffset + viewportSize);
if (endBuffer < this._minBufferPx && newRange.end != dataLength) {
const expandEnd = Math.ceil((this._maxBufferPx - endBuffer) / this._itemSize);
if (expandEnd > 0) {
newRange.end = Math.min(dataLength, newRange.end + expandEnd);
newRange.start = Math.max(0, Math.floor(firstVisibleIndex - this._minBufferPx / this._itemSize));
}
}
}
this._viewport.setRenderedRange(newRange);
this._viewport.setRenderedContentOffset(this._itemSize * newRange.start);
this._scrolledIndexChange.next(Math.floor(firstVisibleIndex));
}
}
/**
* Provider factory for `FixedSizeVirtualScrollStrategy` that simply extracts the already created
* `FixedSizeVirtualScrollStrategy` from the given directive.
* @param fixedSizeDir The instance of `CdkFixedSizeVirtualScroll` to extract the
* `FixedSizeVirtualScrollStrategy` from.
*/
function _fixedSizeVirtualScrollStrategyFactory(fixedSizeDir) {
return fixedSizeDir._scrollStrategy;
}
/** A virtual scroll strategy that supports fixed-size items. */
class CdkFixedSizeVirtualScroll {
/** The size of the items in the list (in pixels). */
get itemSize() {
return this._itemSize;
}
set itemSize(value) {
this._itemSize = coerceNumberProperty(value);
}
_itemSize = 20;
/**
* The minimum amount of buffer rendered beyond the viewport (in pixels).
* If the amount of buffer dips below this number, more items will be rendered. Defaults to 100px.
*/
get minBufferPx() {
return this._minBufferPx;
}
set minBufferPx(value) {
this._minBufferPx = coerceNumberProperty(value);
}
_minBufferPx = 100;
/**
* The number of pixels worth of buffer to render for when rendering new items. Defaults to 200px.
*/
get maxBufferPx() {
return this._maxBufferPx;
}
set maxBufferPx(value) {
this._maxBufferPx = coerceNumberProperty(value);
}
_maxBufferPx = 200;
/** The scroll strategy used by this directive. */
_scrollStrategy = new FixedSizeVirtualScrollStrategy(this.itemSize, this.minBufferPx, this.maxBufferPx);
ngOnChanges() {
this._scrollStrategy.updateItemAndBufferSize(this.itemSize, this.minBufferPx, this.maxBufferPx);
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkFixedSizeVirtualScroll, deps: [], target: i0.ɵɵFactoryTarget.Directive });
static ɵdir = i0.ɵɵngDeclareDirective({ minVersion: "14.0.0", version: "19.2.0", type: CdkFixedSizeVirtualScroll, isStandalone: true, selector: "cdk-virtual-scroll-viewport[itemSize]", inputs: { itemSize: "itemSize", minBufferPx: "minBufferPx", maxBufferPx: "maxBufferPx" }, providers: [
{
provide: VIRTUAL_SCROLL_STRATEGY,
useFactory: _fixedSizeVirtualScrollStrategyFactory,
deps: [forwardRef(() => CdkFixedSizeVirtualScroll)],
},
], usesOnChanges: true, ngImport: i0 });
}
i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkFixedSizeVirtualScroll, decorators: [{
type: Directive,
args: [{
selector: 'cdk-virtual-scroll-viewport[itemSize]',
providers: [
{
provide: VIRTUAL_SCROLL_STRATEGY,
useFactory: _fixedSizeVirtualScrollStrategyFactory,
deps: [forwardRef(() => CdkFixedSizeVirtualScroll)],
},
],
}]
}], propDecorators: { itemSize: [{
type: Input
}], minBufferPx: [{
type: Input
}], maxBufferPx: [{
type: Input
}] } });
/** Time in ms to throttle the scrolling events by default. */
const DEFAULT_SCROLL_TIME = 20;
/**
* Service contained all registered Scrollable references and emits an event when any one of the
* Scrollable references emit a scrolled event.
*/
class ScrollDispatcher {
_ngZone = inject(NgZone);
_platform = inject(Platform);
_renderer = inject(RendererFactory2).createRenderer(null, null);
_cleanupGlobalListener;
constructor() { }
/** Subject for notifying that a registered scrollable reference element has been scrolled. */
_scrolled = new Subject();
/** Keeps track of the amount of subscriptions to `scrolled`. Used for cleaning up afterwards. */
_scrolledCount = 0;
/**
* Map of all the scrollable references that are registered with the service and their
* scroll event subscriptions.
*/
scrollContainers = new Map();
/**
* Registers a scrollable instance with the service and listens for its scrolled events. When the
* scrollable is scrolled, the service emits the event to its scrolled observable.
* @param scrollable Scrollable instance to be registered.
*/
register(scrollable) {
if (!this.scrollContainers.has(scrollable)) {
this.scrollContainers.set(scrollable, scrollable.elementScrolled().subscribe(() => this._scrolled.next(scrollable)));
}
}
/**
* De-registers a Scrollable reference and unsubscribes from its scroll event observable.
* @param scrollable Scrollable instance to be deregistered.
*/
deregister(scrollable) {
const scrollableReference = this.scrollContainers.get(scrollable);
if (scrollableReference) {
scrollableReference.unsubscribe();
this.scrollContainers.delete(scrollable);
}
}
/**
* Returns an observable that emits an event whenever any of the registered Scrollable
* references (or window, document, or body) fire a scrolled event. Can provide a time in ms
* to override the default "throttle" time.
*
* **Note:** in order to avoid hitting change detection for every scroll event,
* all of the events emitted from this stream will be run outside the Angular zone.
* If you need to update any data bindings as a result of a scroll event, you have
* to run the callback using `NgZone.run`.
*/
scrolled(auditTimeInMs = DEFAULT_SCROLL_TIME) {
if (!this._platform.isBrowser) {
return of();
}
return new Observable((observer) => {
if (!this._cleanupGlobalListener) {
this._cleanupGlobalListener = this._ngZone.runOutsideAngular(() => this._renderer.listen('document', 'scroll', () => this._scrolled.next()));
}
// In the case of a 0ms delay, use an observable without auditTime
// since it does add a perceptible delay in processing overhead.
const subscription = auditTimeInMs > 0
? this._scrolled.pipe(auditTime(auditTimeInMs)).subscribe(observer)
: this._scrolled.subscribe(observer);
this._scrolledCount++;
return () => {
subscription.unsubscribe();
this._scrolledCount--;
if (!this._scrolledCount) {
this._cleanupGlobalListener?.();
this._cleanupGlobalListener = undefined;
}
};
});
}
ngOnDestroy() {
this._cleanupGlobalListener?.();
this._cleanupGlobalListener = undefined;
this.scrollContainers.forEach((_, container) => this.deregister(container));
this._scrolled.complete();
}
/**
* Returns an observable that emits whenever any of the
* scrollable ancestors of an element are scrolled.
* @param elementOrElementRef Element whose ancestors to listen for.
* @param auditTimeInMs Time to throttle the scroll events.
*/
ancestorScrolled(elementOrElementRef, auditTimeInMs) {
const ancestors = this.getAncestorScrollContainers(elementOrElementRef);
return this.scrolled(auditTimeInMs).pipe(filter(target => !target || ancestors.indexOf(target) > -1));
}
/** Returns all registered Scrollables that contain the provided element. */
getAncestorScrollContainers(elementOrElementRef) {
const scrollingContainers = [];
this.scrollContainers.forEach((_subscription, scrollable) => {
if (this._scrollableContainsElement(scrollable, elementOrElementRef)) {
scrollingContainers.push(scrollable);
}
});
return scrollingContainers;
}
/** Returns true if the element is contained within the provided Scrollable. */
_scrollableContainsElement(scrollable, elementOrElementRef) {
let element = coerceElement(elementOrElementRef);
let scrollableElement = scrollable.getElementRef().nativeElement;
// Traverse through the element parents until we reach null, checking if any of the elements
// are the scrollable's element.
do {
if (element == scrollableElement) {
return true;
}
} while ((element = element.parentElement));
return false;
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ScrollDispatcher, deps: [], target: i0.ɵɵFactoryTarget.Injectable });
static ɵprov = i0.ɵɵngDeclareInjectable({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ScrollDispatcher, providedIn: 'root' });
}
i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ScrollDispatcher, decorators: [{
type: Injectable,
args: [{ providedIn: 'root' }]
}], ctorParameters: () => [] });
/**
* Sends an event when the directive's element is scrolled. Registers itself with the
* ScrollDispatcher service to include itself as part of its collection of scrolling events that it
* can be listened to through the service.
*/
class CdkScrollable {
elementRef = inject(ElementRef);
scrollDispatcher = inject(ScrollDispatcher);
ngZone = inject(NgZone);
dir = inject(Directionality, { optional: true });
_scrollElement = this.elementRef.nativeElement;
_destroyed = new Subject();
_renderer = inject(Renderer2);
_cleanupScroll;
_elementScrolled = new Subject();
constructor() { }
ngOnInit() {
this._cleanupScroll = this.ngZone.runOutsideAngular(() => this._renderer.listen(this._scrollElement, 'scroll', event => this._elementScrolled.next(event)));
this.scrollDispatcher.register(this);
}
ngOnDestroy() {
this._cleanupScroll?.();
this._elementScrolled.complete();
this.scrollDispatcher.deregister(this);
this._destroyed.next();
this._destroyed.complete();
}
/** Returns observable that emits when a scroll event is fired on the host element. */
elementScrolled() {
return this._elementScrolled;
}
/** Gets the ElementRef for the viewport. */
getElementRef() {
return this.elementRef;
}
/**
* Scrolls to the specified offsets. This is a normalized version of the browser's native scrollTo
* method, since browsers are not consistent about what scrollLeft means in RTL. For this method
* left and right always refer to the left and right side of the scrolling container irrespective
* of the layout direction. start and end refer to left and right in an LTR context and vice-versa
* in an RTL context.
* @param options specified the offsets to scroll to.
*/
scrollTo(options) {
const el = this.elementRef.nativeElement;
const isRtl = this.dir && this.dir.value == 'rtl';
// Rewrite start & end offsets as right or left offsets.
if (options.left == null) {
options.left = isRtl ? options.end : options.start;
}
if (options.right == null) {
options.right = isRtl ? options.start : options.end;
}
// Rewrite the bottom offset as a top offset.
if (options.bottom != null) {
options.top =
el.scrollHeight - el.clientHeight - options.bottom;
}
// Rewrite the right offset as a left offset.
if (isRtl && getRtlScrollAxisType() != RtlScrollAxisType.NORMAL) {
if (options.left != null) {
options.right =
el.scrollWidth - el.clientWidth - options.left;
}
if (getRtlScrollAxisType() == RtlScrollAxisType.INVERTED) {
options.left = options.right;
}
else if (getRtlScrollAxisType() == RtlScrollAxisType.NEGATED) {
options.left = options.right ? -options.right : options.right;
}
}
else {
if (options.right != null) {
options.left =
el.scrollWidth - el.clientWidth - options.right;
}
}
this._applyScrollToOptions(options);
}
_applyScrollToOptions(options) {
const el = this.elementRef.nativeElement;
if (supportsScrollBehavior()) {
el.scrollTo(options);
}
else {
if (options.top != null) {
el.scrollTop = options.top;
}
if (options.left != null) {
el.scrollLeft = options.left;
}
}
}
/**
* Measures the scroll offset relative to the specified edge of the viewport. This method can be
* used instead of directly checking scrollLeft or scrollTop, since browsers are not consistent
* about what scrollLeft means in RTL. The values returned by this method are normalized such that
* left and right always refer to the left and right side of the scrolling container irrespective
* of the layout direction. start and end refer to left and right in an LTR context and vice-versa
* in an RTL context.
* @param from The edge to measure from.
*/
measureScrollOffset(from) {
const LEFT = 'left';
const RIGHT = 'right';
const el = this.elementRef.nativeElement;
if (from == 'top') {
return el.scrollTop;
}
if (from == 'bottom') {
return el.scrollHeight - el.clientHeight - el.scrollTop;
}
// Rewrite start & end as left or right offsets.
const isRtl = this.dir && this.dir.value == 'rtl';
if (from == 'start') {
from = isRtl ? RIGHT : LEFT;
}
else if (from == 'end') {
from = isRtl ? LEFT : RIGHT;
}
if (isRtl && getRtlScrollAxisType() == RtlScrollAxisType.INVERTED) {
// For INVERTED, scrollLeft is (scrollWidth - clientWidth) when scrolled all the way left and
// 0 when scrolled all the way right.
if (from == LEFT) {
return el.scrollWidth - el.clientWidth - el.scrollLeft;
}
else {
return el.scrollLeft;
}
}
else if (isRtl && getRtlScrollAxisType() == RtlScrollAxisType.NEGATED) {
// For NEGATED, scrollLeft is -(scrollWidth - clientWidth) when scrolled all the way left and
// 0 when scrolled all the way right.
if (from == LEFT) {
return el.scrollLeft + el.scrollWidth - el.clientWidth;
}
else {
return -el.scrollLeft;
}
}
else {
// For NORMAL, as well as non-RTL contexts, scrollLeft is 0 when scrolled all the way left and
// (scrollWidth - clientWidth) when scrolled all the way right.
if (from == LEFT) {
return el.scrollLeft;
}
else {
return el.scrollWidth - el.clientWidth - el.scrollLeft;
}
}
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkScrollable, deps: [], target: i0.ɵɵFactoryTarget.Directive });
static ɵdir = i0.ɵɵngDeclareDirective({ minVersion: "14.0.0", version: "19.2.0", type: CdkScrollable, isStandalone: true, selector: "[cdk-scrollable], [cdkScrollable]", ngImport: i0 });
}
i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkScrollable, decorators: [{
type: Directive,
args: [{
selector: '[cdk-scrollable], [cdkScrollable]',
}]
}], ctorParameters: () => [] });
/** Time in ms to throttle the resize events by default. */
const DEFAULT_RESIZE_TIME = 20;
/**
* Simple utility for getting the bounds of the browser viewport.
* @docs-private
*/
class ViewportRuler {
_platform = inject(Platform);
_listeners;
/** Cached viewport dimensions. */
_viewportSize;
/** Stream of viewport change events. */
_change = new Subject();
/** Used to reference correct document/window */
_document = inject(DOCUMENT, { optional: true });
constructor() {
const ngZone = inject(NgZone);
const renderer = inject(RendererFactory2).createRenderer(null, null);
ngZone.runOutsideAngular(() => {
if (this._platform.isBrowser) {
const changeListener = (event) => this._change.next(event);
this._listeners = [
renderer.listen('window', 'resize', changeListener),
renderer.listen('window', 'orientationchange', changeListener),
];
}
// Clear the cached position so that the viewport is re-measured next time it is required.
// We don't need to keep track of the subscription, because it is completed on destroy.
this.change().subscribe(() => (this._viewportSize = null));
});
}
ngOnDestroy() {
this._listeners?.forEach(cleanup => cleanup());
this._change.complete();
}
/** Returns the viewport's width and height. */
getViewportSize() {
if (!this._viewportSize) {
this._updateViewportSize();
}
const output = { width: this._viewportSize.width, height: this._viewportSize.height };
// If we're not on a browser, don't cache the size since it'll be mocked out anyway.
if (!this._platform.isBrowser) {
this._viewportSize = null;
}
return output;
}
/** Gets a DOMRect for the viewport's bounds. */
getViewportRect() {
// Use the document element's bounding rect rather than the window scroll properties
// (e.g. pageYOffset, scrollY) due to in issue in Chrome and IE where window scroll
// properties and client coordinates (boundingClientRect, clientX/Y, etc.) are in different
// conceptual viewports. Under most circumstances these viewports are equivalent, but they
// can disagree when the page is pinch-zoomed (on devices that support touch).
// See https://bugs.chromium.org/p/chromium/issues/detail?id=489206#c4
// We use the documentElement instead of the body because, by default (without a css reset)
// browsers typically give the document body an 8px margin, which is not included in
// getBoundingClientRect().
const scrollPosition = this.getViewportScrollPosition();
const { width, height } = this.getViewportSize();
return {
top: scrollPosition.top,
left: scrollPosition.left,
bottom: scrollPosition.top + height,
right: scrollPosition.left + width,
height,
width,
};
}
/** Gets the (top, left) scroll position of the viewport. */
getViewportScrollPosition() {
// While we can get a reference to the fake document
// during SSR, it doesn't have getBoundingClientRect.
if (!this._platform.isBrowser) {
return { top: 0, left: 0 };
}
// The top-left-corner of the viewport is determined by the scroll position of the document
// body, normally just (scrollLeft, scrollTop). However, Chrome and Firefox disagree about
// whether `document.body` or `document.documentElement` is the scrolled element, so reading
// `scrollTop` and `scrollLeft` is inconsistent. However, using the bounding rect of
// `document.documentElement` works consistently, where the `top` and `left` values will
// equal negative the scroll position.
const document = this._document;
const window = this._getWindow();
const documentElement = document.documentElement;
const documentRect = documentElement.getBoundingClientRect();
const top = -documentRect.top ||
document.body.scrollTop ||
window.scrollY ||
documentElement.scrollTop ||
0;
const left = -documentRect.left ||
document.body.scrollLeft ||
window.scrollX ||
documentElement.scrollLeft ||
0;
return { top, left };
}
/**
* Returns a stream that emits whenever the size of the viewport changes.
* This stream emits outside of the Angular zone.
* @param throttleTime Time in milliseconds to throttle the stream.
*/
change(throttleTime = DEFAULT_RESIZE_TIME) {
return throttleTime > 0 ? this._change.pipe(auditTime(throttleTime)) : this._change;
}
/** Use defaultView of injected document if available or fallback to global window reference */
_getWindow() {
return this._document.defaultView || window;
}
/** Updates the cached viewport size. */
_updateViewportSize() {
const window = this._getWindow();
this._viewportSize = this._platform.isBrowser
? { width: window.innerWidth, height: window.innerHeight }
: { width: 0, height: 0 };
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ViewportRuler, deps: [], target: i0.ɵɵFactoryTarget.Injectable });
static ɵprov = i0.ɵɵngDeclareInjectable({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ViewportRuler, providedIn: 'root' });
}
i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: ViewportRuler, decorators: [{
type: Injectable,
args: [{ providedIn: 'root' }]
}], ctorParameters: () => [] });
const VIRTUAL_SCROLLABLE = new InjectionToken('VIRTUAL_SCROLLABLE');
/**
* Extending the {@link CdkScrollable} to be used as scrolling container for virtual scrolling.
*/
class CdkVirtualScrollable extends CdkScrollable {
constructor() {
super();
}
/**
* Measure the viewport size for the provided orientation.
*
* @param orientation The orientation to measure the size from.
*/
measureViewportSize(orientation) {
const viewportEl = this.elementRef.nativeElement;
return orientation === 'horizontal' ? viewportEl.clientWidth : viewportEl.clientHeight;
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkVirtualScrollable, deps: [], target: i0.ɵɵFactoryTarget.Directive });
static ɵdir = i0.ɵɵngDeclareDirective({ minVersion: "14.0.0", version: "19.2.0", type: CdkVirtualScrollable, isStandalone: true, usesInheritance: true, ngImport: i0 });
}
i0.ɵɵngDeclareClassMetadata({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkVirtualScrollable, decorators: [{
type: Directive
}], ctorParameters: () => [] });
/** Checks if the given ranges are equal. */
function rangesEqual(r1, r2) {
return r1.start == r2.start && r1.end == r2.end;
}
/**
* Scheduler to be used for scroll events. Needs to fall back to
* something that doesn't rely on requestAnimationFrame on environments
* that don't support it (e.g. server-side rendering).
*/
const SCROLL_SCHEDULER = typeof requestAnimationFrame !== 'undefined' ? animationFrameScheduler : asapScheduler;
/** A viewport that virtualizes its scrolling with the help of `CdkVirtualForOf`. */
class CdkVirtualScrollViewport extends CdkVirtualScrollable {
elementRef = inject(ElementRef);
_changeDetectorRef = inject(ChangeDetectorRef);
_scrollStrategy = inject(VIRTUAL_SCROLL_STRATEGY, {
optional: true,
});
scrollable = inject(VIRTUAL_SCROLLABLE, { optional: true });
_platform = inject(Platform);
/** Emits when the viewport is detached from a CdkVirtualForOf. */
_detachedSubject = new Subject();
/** Emits when the rendered range changes. */
_renderedRangeSubject = new Subject();
/** The direction the viewport scrolls. */
get orientation() {
return this._orientation;
}
set orientation(orientation) {
if (this._orientation !== orientation) {
this._orientation = orientation;
this._calculateSpacerSize();
}
}
_orientation = 'vertical';
/**
* Whether rendered items should persist in the DOM after scrolling out of view. By default, items
* will be removed.
*/
appendOnly = false;
// Note: we don't use the typical EventEmitter here because we need to subscribe to the scroll
// strategy lazily (i.e. only if the user is actually listening to the events). We do this because
// depending on how the strategy calculates the scrolled index, it may come at a cost to
// performance.
/** Emits when the index of the first element visible in the viewport changes. */
scrolledIndexChange = new Observable((observer) => this._scrollStrategy.scrolledIndexChange.subscribe(index => Promise.resolve().then(() => this.ngZone.run(() => observer.next(index)))));
/** The element that wraps the rendered content. */
_contentWrapper;
/** A stream that emits whenever the rendered range changes. */
renderedRangeStream = this._renderedRangeSubject;
/**
* The total size of all content (in pixels), including content that is not currently rendered.
*/
_totalContentSize = 0;
/** A string representing the `style.width` property value to be used for the spacer element. */
_totalContentWidth = '';
/** A string representing the `style.height` property value to be used for the spacer element. */
_totalContentHeight = '';
/**
* The CSS transform applied to the rendered subset of items so that they appear within the bounds
* of the visible viewport.
*/
_renderedContentTransform;
/** The currently rendered range of indices. */
_renderedRange = { start: 0, end: 0 };
/** The length of the data bound to this viewport (in number of items). */
_dataLength = 0;
/** The size of the viewport (in pixels). */
_viewportSize = 0;
/** the currently attached CdkVirtualScrollRepeater. */
_forOf;
/** The last rendered content offset that was set. */
_renderedContentOffset = 0;
/**
* Whether the last rendered content offset was to the end of the content (and therefore needs to
* be rewritten as an offset to the start of the content).
*/
_renderedContentOffsetNeedsRewrite = false;
/** Whether there is a pending change detection cycle. */
_isChangeDetectionPending = false;
/** A list of functions to run after the next change detection cycle. */
_runAfterChangeDetection = [];
/** Subscription to changes in the viewport size. */
_viewportChanges = Subscription.EMPTY;
_injector = inject(Injector);
_isDestroyed = false;
constructor() {
super();
const viewportRuler = inject(ViewportRuler);
if (!this._scrollStrategy && (typeof ngDevMode === 'undefined' || ngDevMode)) {
throw Error('Error: cdk-virtual-scroll-viewport requires the "itemSize" property to be set.');
}
this._viewportChanges = viewportRuler.change().subscribe(() => {
this.checkViewportSize();
});
if (!this.scrollable) {
// No scrollable is provided, so the virtual-scroll-viewport needs to become a scrollable
this.elementRef.nativeElement.classList.add('cdk-virtual-scrollable');
this.scrollable = this;
}
}
ngOnInit() {
// Scrolling depends on the element dimensions which we can't get during SSR.
if (!this._platform.isBrowser) {
return;
}
if (this.scrollable === this) {
super.ngOnInit();
}
// It's still too early to measure the viewport at this point. Deferring with a promise allows
// the Viewport to be rendered with the correct size before we measure. We run this outside the
// zone to avoid causing more change detection cycles. We handle the change detection loop
// ourselves instead.
this.ngZone.runOutsideAngular(() => Promise.resolve().then(() => {
this._measureViewportSize();
this._scrollStrategy.attach(this);
this.scrollable
.elementScrolled()
.pipe(
// Start off with a fake scroll event so we properly detect our initial position.
startWith(null),
// Collect multiple events into one until the next animation frame. This way if
// there are multiple scroll events in the same frame we only need to recheck
// our layout once.
auditTime(0, SCROLL_SCHEDULER),
// Usually `elementScrolled` is completed when the scrollable is destroyed, but
// that may not be the case if a `CdkVirtualScrollableElement` is used so we have
// to unsubscribe here just in case.
takeUntil(this._destroyed))
.subscribe(() => this._scrollStrategy.onContentScrolled());
this._markChangeDetectionNeeded();
}));
}
ngOnDestroy() {
this.detach();
this._scrollStrategy.detach();
// Complete all subjects
this._renderedRangeSubject.complete();
this._detachedSubject.complete();
this._viewportChanges.unsubscribe();
this._isDestroyed = true;
super.ngOnDestroy();
}
/** Attaches a `CdkVirtualScrollRepeater` to this viewport. */
attach(forOf) {
if (this._forOf && (typeof ngDevMode === 'undefined' || ngDevMode)) {
throw Error('CdkVirtualScrollViewport is already attached.');
}
// Subscribe to the data stream of the CdkVirtualForOf to keep track of when the data length
// changes. Run outside the zone to avoid triggering change detection, since we're managing the
// change detection loop ourselves.
this.ngZone.runOutsideAngular(() => {
this._forOf = forOf;
this._forOf.dataStream.pipe(takeUntil(this._detachedSubject)).subscribe(data => {
const newLength = data.length;
if (newLength !== this._dataLength) {
this._dataLength = newLength;
this._scrollStrategy.onDataLengthChanged();
}
this._doChangeDetection();
});
});
}
/** Detaches the current `CdkVirtualForOf`. */
detach() {
this._forOf = null;
this._detachedSubject.next();
}
/** Gets the length of the data bound to this viewport (in number of items). */
getDataLength() {
return this._dataLength;
}
/** Gets the size of the viewport (in pixels). */
getViewportSize() {
return this._viewportSize;
}
// TODO(mmalerba): This is technically out of sync with what's really rendered until a render
// cycle happens. I'm being careful to only call it after the render cycle is complete and before
// setting it to something else, but its error prone and should probably be split into
// `pendingRange` and `renderedRange`, the latter reflecting whats actually in the DOM.
/** Get the current rendered range of items. */
getRenderedRange() {
return this._renderedRange;
}
measureBoundingClientRectWithScrollOffset(from) {
return this.getElementRef().nativeElement.getBoundingClientRect()[from];
}
/**
* Sets the total size of all content (in pixels), including content that is not currently
* rendered.
*/
setTotalContentSize(size) {
if (this._totalContentSize !== size) {
this._totalContentSize = size;
this._calculateSpacerSize();
this._markChangeDetectionNeeded();
}
}
/** Sets the currently rendered range of indices. */
setRenderedRange(range) {
if (!rangesEqual(this._renderedRange, range)) {
if (this.appendOnly) {
range = { start: 0, end: Math.max(this._renderedRange.end, range.end) };
}
this._renderedRangeSubject.next((this._renderedRange = range));
this._markChangeDetectionNeeded(() => this._scrollStrategy.onContentRendered());
}
}
/**
* Gets the offset from the start of the viewport to the start of the rendered data (in pixels).
*/
getOffsetToRenderedContentStart() {
return this._renderedContentOffsetNeedsRewrite ? null : this._renderedContentOffset;
}
/**
* Sets the offset from the start of the viewport to either the start or end of the rendered data
* (in pixels).
*/
setRenderedContentOffset(offset, to = 'to-start') {
// In appendOnly, we always start from the top
offset = this.appendOnly && to === 'to-start' ? 0 : offset;
// For a horizontal viewport in a right-to-left language we need to translate along the x-axis
// in the negative direction.
const isRtl = this.dir && this.dir.value == 'rtl';
const isHorizontal = this.orientation == 'horizontal';
const axis = isHorizontal ? 'X' : 'Y';
const axisDirection = isHorizontal && isRtl ? -1 : 1;
let transform = `translate${axis}(${Number(axisDirection * offset)}px)`;
this._renderedContentOffset = offset;
if (to === 'to-end') {
transform += ` translate${axis}(-100%)`;
// The viewport should rewrite this as a `to-start` offset on the next render cycle. Otherwise
// elements will appear to expand in the wrong direction (e.g. `mat-expansion-panel` would
// expand upward).
this._renderedContentOffsetNeedsRewrite = true;
}
if (this._renderedContentTransform != transform) {
// We know this value is safe because we parse `offset` with `Number()` before passing it
// into the string.
this._renderedContentTransform = transform;
this._markChangeDetectionNeeded(() => {
if (this._renderedContentOffsetNeedsRewrite) {
this._renderedContentOffset -= this.measureRenderedContentSize();
this._renderedContentOffsetNeedsRewrite = false;
this.setRenderedContentOffset(this._renderedContentOffset);
}
else {
this._scrollStrategy.onRenderedOffsetChanged();
}
});
}
}
/**
* Scrolls to the given offset from the start of the viewport. Please note that this is not always
* the same as setting `scrollTop` or `scrollLeft`. In a horizontal viewport with right-to-left
* direction, this would be the equivalent of setting a fictional `scrollRight` property.
* @param offset The offset to scroll to.
* @param behavior The ScrollBehavior to use when scrolling. Default is behavior is `auto`.
*/
scrollToOffset(offset, behavior = 'auto') {
const options = { behavior };
if (this.orientation === 'horizontal') {
options.start = offset;
}
else {
options.top = offset;
}
this.scrollable.scrollTo(options);
}
/**
* Scrolls to the offset for the given index.
* @param index The index of the element to scroll to.
* @param behavior The ScrollBehavior to use when scrolling. Default is behavior is `auto`.
*/
scrollToIndex(index, behavior = 'auto') {
this._scrollStrategy.scrollToIndex(index, behavior);
}
/**
* Gets the current scroll offset from the start of the scrollable (in pixels).
* @param from The edge to measure the offset from. Defaults to 'top' in vertical mode and 'start'
* in horizontal mode.
*/
measureScrollOffset(from) {
// This is to break the call cycle
let measureScrollOffset;
if (this.scrollable == this) {
measureScrollOffset = (_from) => super.measureScrollOffset(_from);
}
else {
measureScrollOffset = (_from) => this.scrollable.measureScrollOffset(_from);
}
return Math.max(0, measureScrollOffset(from ?? (this.orientation === 'horizontal' ? 'start' : 'top')) -
this.measureViewportOffset());
}
/**
* Measures the offset of the viewport from the scrolling container
* @param from The edge to measure from.
*/
measureViewportOffset(from) {
let fromRect;
const LEFT = 'left';
const RIGHT = 'right';
const isRtl = this.dir?.value == 'rtl';
if (from == 'start') {
fromRect = isRtl ? RIGHT : LEFT;
}
else if (from == 'end') {
fromRect = isRtl ? LEFT : RIGHT;
}
else if (from) {
fromRect = from;
}
else {
fromRect = this.orientation === 'horizontal' ? 'left' : 'top';
}
const scrollerClientRect = this.scrollable.measureBoundingClientRectWithScrollOffset(fromRect);
const viewportClientRect = this.elementRef.nativeElement.getBoundingClientRect()[fromRect];
return viewportClientRect - scrollerClientRect;
}
/** Measure the combined size of all of the rendered items. */
measureRenderedContentSize() {
const contentEl = this._contentWrapper.nativeElement;
return this.orientation === 'horizontal' ? contentEl.offsetWidth : contentEl.offsetHeight;
}
/**
* Measure the total combined size of the given range. Throws if the range includes items that are
* not rendered.
*/
measureRangeSize(range) {
if (!this._forOf) {
return 0;
}
return this._forOf.measureRangeSize(range, this.orientation);
}
/** Update the viewport dimensions and re-render. */
checkViewportSize() {
// TODO: Cleanup later when add logic for handling content resize
this._measureViewportSize();
this._scrollStrategy.onDataLengthChanged();
}
/** Measure the viewport size. */
_measureViewportSize() {
this._viewportSize = this.scrollable.measureViewportSize(this.orientation);
}
/** Queue up change detection to run. */
_markChangeDetectionNeeded(runAfter) {
if (runAfter) {
this._runAfterChangeDetection.push(runAfter);
}
// Use a Promise to batch together calls to `_doChangeDetection`. This way if we set a bunch of
// properties sequentially we only have to run `_doChangeDetection` once at the end.
if (!this._isChangeDetectionPending) {
this._isChangeDetectionPending = true;
this.ngZone.runOutsideAngular(() => Promise.resolve().then(() => {
this._doChangeDetection();
}));
}
}
/** Run change detection. */
_doChangeDetection() {
if (this._isDestroyed) {
return;
}
this.ngZone.run(() => {
// Apply changes to Angular bindings. Note: We must call `markForCheck` to run change detection
// from the root, since the repeated items are content projected in. Calling `detectChanges`
// instead does not properly check the projected content.
this._changeDetectorRef.markForCheck();
// Apply the content transform. The transform can't be set via an Angular binding because
// bypassSecurityTrustStyle is banned in Google. However the value is safe, it's composed of
// string literals, a variable that can only be 'X' or 'Y', and user input that is run through
// the `Number` function first to coerce it to a numeric value.
this._contentWrapper.nativeElement.style.transform = this._renderedContentTransform;
afterNextRender(() => {
this._isChangeDetectionPending = false;
const runAfterChangeDetection = this._runAfterChangeDetection;
this._runAfterChangeDetection = [];
for (const fn of runAfterChangeDetection) {
fn();
}
}, { injector: this._injector });
});
}
/** Calculates the `style.width` and `style.height` for the spacer element. */
_calculateSpacerSize() {
this._totalContentHeight =
this.orientation === 'horizontal' ? '' : `${this._totalContentSize}px`;
this._totalContentWidth =
this.orientation === 'horizontal' ? `${this._totalContentSize}px` : '';
}
static ɵfac = i0.ɵɵngDeclareFactory({ minVersion: "12.0.0", version: "19.2.0", ngImport: i0, type: CdkVirtualScrollViewport, deps: [], target: i0.ɵɵFactoryTarget.Component });
static ɵcmp = i0.ɵɵngDeclareComponent({ minVersion: "16.1.0", version: "19.2.0", type: CdkVirtualScrollViewport, isStandalone: true, selector: "cdk-virtual-scroll-viewport", inputs: { orientation: "orientation", appendOnly: ["appendOnly", "appendOnly", booleanAttribute] }, outputs: { scrolledIndexChange: "scrolledIndexChange" }, host: { properties: { "class.cdk-virtual-scroll-orientation-horizontal": "orientation === \"horizontal\"", "class.cdk-virtual-scroll-orientation-vertical": "orientation !== \"horizontal\"" }, classAttribute: "cdk-virtual-scroll-viewport" }, providers: [
{
provide: CdkScrollable,
useFactory: (virtualScrollable, viewport) => virtualScrollable || viewport,
deps: [[new Optional(), new Inject(VIRTUAL_SCROLLABLE)], CdkVirtualScrollViewport],
},
], viewQueries: [{ propertyName: "_contentWrapper", first: true, predicate: ["contentWrapper"], descendants: true, static: true }], usesInheritance: true, ngImport: i0, template: "<!--\n Wrap the rendered content in an element that will be used to offset it based on the scroll\n position.\n-->\n<div #contentWrapper class=\"cdk-virtual-scroll-