UNPKG

@angular/cdk

Version:

Angular Material Component Development Kit

1 lines 13.7 kB
{"version":3,"file":"observers.mjs","sources":["../../../../../darwin_arm64-fastbuild-ST-46c76129e412/bin/src/cdk/observers/observe-content.ts"],"sourcesContent":["/**\n * @license\n * Copyright Google LLC All Rights Reserved.\n *\n * Use of this source code is governed by an MIT-style license that can be\n * found in the LICENSE file at https://angular.dev/license\n */\n\nimport {NumberInput, coerceElement, coerceNumberProperty} from '../coercion';\nimport {\n AfterContentInit,\n Directive,\n ElementRef,\n EventEmitter,\n Injectable,\n Input,\n NgModule,\n NgZone,\n OnDestroy,\n Output,\n booleanAttribute,\n inject,\n} from '@angular/core';\nimport {Observable, Observer, Subject, Subscription} from 'rxjs';\nimport {debounceTime, filter, map} from 'rxjs/operators';\n\n// Angular may add, remove, or edit comment nodes during change detection. We don't care about\n// these changes because they don't affect the user-preceived content, and worse it can cause\n// infinite change detection cycles where the change detection updates a comment, triggering the\n// MutationObserver, triggering another change detection and kicking the cycle off again.\nfunction shouldIgnoreRecord(record: MutationRecord) {\n // Ignore changes to comment text.\n if (record.type === 'characterData' && record.target instanceof Comment) {\n return true;\n }\n // Ignore addition / removal of comments.\n if (record.type === 'childList') {\n for (let i = 0; i < record.addedNodes.length; i++) {\n if (!(record.addedNodes[i] instanceof Comment)) {\n return false;\n }\n }\n for (let i = 0; i < record.removedNodes.length; i++) {\n if (!(record.removedNodes[i] instanceof Comment)) {\n return false;\n }\n }\n return true;\n }\n // Observe everything else.\n return false;\n}\n\n/**\n * Factory that creates a new MutationObserver and allows us to stub it out in unit tests.\n * @docs-private\n */\n@Injectable({providedIn: 'root'})\nexport class MutationObserverFactory {\n create(callback: MutationCallback): MutationObserver | null {\n return typeof MutationObserver === 'undefined' ? null : new MutationObserver(callback);\n }\n}\n\n/** An injectable service that allows watching elements for changes to their content. */\n@Injectable({providedIn: 'root'})\nexport class ContentObserver implements OnDestroy {\n private _mutationObserverFactory = inject(MutationObserverFactory);\n\n /** Keeps track of the existing MutationObservers so they can be reused. */\n private _observedElements = new Map<\n Element,\n {\n observer: MutationObserver | null;\n readonly stream: Subject<MutationRecord[]>;\n count: number;\n }\n >();\n\n private _ngZone = inject(NgZone);\n\n constructor(...args: unknown[]);\n constructor() {}\n\n ngOnDestroy() {\n this._observedElements.forEach((_, element) => this._cleanupObserver(element));\n }\n\n /**\n * Observe content changes on an element.\n * @param element The element to observe for content changes.\n */\n observe(element: Element): Observable<MutationRecord[]>;\n\n /**\n * Observe content changes on an element.\n * @param element The element to observe for content changes.\n */\n observe(element: ElementRef<Element>): Observable<MutationRecord[]>;\n\n observe(elementOrRef: Element | ElementRef<Element>): Observable<MutationRecord[]> {\n const element = coerceElement(elementOrRef);\n\n return new Observable((observer: Observer<MutationRecord[]>) => {\n const stream = this._observeElement(element);\n const subscription = stream\n .pipe(\n map(records => records.filter(record => !shouldIgnoreRecord(record))),\n filter(records => !!records.length),\n )\n .subscribe(records => {\n this._ngZone.run(() => {\n observer.next(records);\n });\n });\n\n return () => {\n subscription.unsubscribe();\n this._unobserveElement(element);\n };\n });\n }\n\n /**\n * Observes the given element by using the existing MutationObserver if available, or creating a\n * new one if not.\n */\n private _observeElement(element: Element): Subject<MutationRecord[]> {\n return this._ngZone.runOutsideAngular(() => {\n if (!this._observedElements.has(element)) {\n const stream = new Subject<MutationRecord[]>();\n const observer = this._mutationObserverFactory.create(mutations => stream.next(mutations));\n if (observer) {\n observer.observe(element, {\n characterData: true,\n childList: true,\n subtree: true,\n });\n }\n this._observedElements.set(element, {observer, stream, count: 1});\n } else {\n this._observedElements.get(element)!.count++;\n }\n return this._observedElements.get(element)!.stream;\n });\n }\n\n /**\n * Un-observes the given element and cleans up the underlying MutationObserver if nobody else is\n * observing this element.\n */\n private _unobserveElement(element: Element) {\n if (this._observedElements.has(element)) {\n this._observedElements.get(element)!.count--;\n if (!this._observedElements.get(element)!.count) {\n this._cleanupObserver(element);\n }\n }\n }\n\n /** Clean up the underlying MutationObserver for the specified element. */\n private _cleanupObserver(element: Element) {\n if (this._observedElements.has(element)) {\n const {observer, stream} = this._observedElements.get(element)!;\n if (observer) {\n observer.disconnect();\n }\n stream.complete();\n this._observedElements.delete(element);\n }\n }\n}\n\n/**\n * Directive that triggers a callback whenever the content of\n * its associated element has changed.\n */\n@Directive({\n selector: '[cdkObserveContent]',\n exportAs: 'cdkObserveContent',\n})\nexport class CdkObserveContent implements AfterContentInit, OnDestroy {\n private _contentObserver = inject(ContentObserver);\n private _elementRef = inject<ElementRef<HTMLElement>>(ElementRef);\n\n /** Event emitted for each change in the element's content. */\n @Output('cdkObserveContent') readonly event = new EventEmitter<MutationRecord[]>();\n\n /**\n * Whether observing content is disabled. This option can be used\n * to disconnect the underlying MutationObserver until it is needed.\n */\n @Input({alias: 'cdkObserveContentDisabled', transform: booleanAttribute})\n get disabled(): boolean {\n return this._disabled;\n }\n set disabled(value: boolean) {\n this._disabled = value;\n this._disabled ? this._unsubscribe() : this._subscribe();\n }\n private _disabled = false;\n\n /** Debounce interval for emitting the changes. */\n @Input()\n get debounce(): number {\n return this._debounce;\n }\n set debounce(value: NumberInput) {\n this._debounce = coerceNumberProperty(value);\n this._subscribe();\n }\n private _debounce: number;\n\n private _currentSubscription: Subscription | null = null;\n\n constructor(...args: unknown[]);\n constructor() {}\n\n ngAfterContentInit() {\n if (!this._currentSubscription && !this.disabled) {\n this._subscribe();\n }\n }\n\n ngOnDestroy() {\n this._unsubscribe();\n }\n\n private _subscribe() {\n this._unsubscribe();\n const stream = this._contentObserver.observe(this._elementRef);\n\n this._currentSubscription = (\n this.debounce ? stream.pipe(debounceTime(this.debounce)) : stream\n ).subscribe(this.event);\n }\n\n private _unsubscribe() {\n this._currentSubscription?.unsubscribe();\n }\n}\n\n@NgModule({\n imports: [CdkObserveContent],\n exports: [CdkObserveContent],\n providers: [MutationObserverFactory],\n})\nexport class ObserversModule {}\n"],"names":[],"mappings":";;;;;;AA0BA;AACA;AACA;AACA;AACA,SAAS,kBAAkB,CAAC,MAAsB,EAAA;;AAEhD,IAAA,IAAI,MAAM,CAAC,IAAI,KAAK,eAAe,IAAI,MAAM,CAAC,MAAM,YAAY,OAAO,EAAE;AACvE,QAAA,OAAO,IAAI;;;AAGb,IAAA,IAAI,MAAM,CAAC,IAAI,KAAK,WAAW,EAAE;AAC/B,QAAA,KAAK,IAAI,CAAC,GAAG,CAAC,EAAE,CAAC,GAAG,MAAM,CAAC,UAAU,CAAC,MAAM,EAAE,CAAC,EAAE,EAAE;AACjD,YAAA,IAAI,EAAE,MAAM,CAAC,UAAU,CAAC,CAAC,CAAC,YAAY,OAAO,CAAC,EAAE;AAC9C,gBAAA,OAAO,KAAK;;;AAGhB,QAAA,KAAK,IAAI,CAAC,GAAG,CAAC,EAAE,CAAC,GAAG,MAAM,CAAC,YAAY,CAAC,MAAM,EAAE,CAAC,EAAE,EAAE;AACnD,YAAA,IAAI,EAAE,MAAM,CAAC,YAAY,CAAC,CAAC,CAAC,YAAY,OAAO,CAAC,EAAE;AAChD,gBAAA,OAAO,KAAK;;;AAGhB,QAAA,OAAO,IAAI;;;AAGb,IAAA,OAAO,KAAK;AACd;AAEA;;;AAGG;MAEU,uBAAuB,CAAA;AAClC,IAAA,MAAM,CAAC,QAA0B,EAAA;AAC/B,QAAA,OAAO,OAAO,gBAAgB,KAAK,WAAW,GAAG,IAAI,GAAG,IAAI,gBAAgB,CAAC,QAAQ,CAAC;;uGAF7E,uBAAuB,EAAA,IAAA,EAAA,EAAA,EAAA,MAAA,EAAA,EAAA,CAAA,eAAA,CAAA,UAAA,EAAA,CAAA;AAAvB,IAAA,OAAA,KAAA,GAAA,EAAA,CAAA,qBAAA,CAAA,EAAA,UAAA,EAAA,QAAA,EAAA,OAAA,EAAA,QAAA,EAAA,QAAA,EAAA,EAAA,EAAA,IAAA,EAAA,uBAAuB,cADX,MAAM,EAAA,CAAA;;2FAClB,uBAAuB,EAAA,UAAA,EAAA,CAAA;kBADnC,UAAU;mBAAC,EAAC,UAAU,EAAE,MAAM,EAAC;;AAOhC;MAEa,eAAe,CAAA;AAClB,IAAA,wBAAwB,GAAG,MAAM,CAAC,uBAAuB,CAAC;;AAG1D,IAAA,iBAAiB,GAAG,IAAI,GAAG,EAOhC;AAEK,IAAA,OAAO,GAAG,MAAM,CAAC,MAAM,CAAC;AAGhC,IAAA,WAAA,GAAA;IAEA,WAAW,GAAA;AACT,QAAA,IAAI,CAAC,iBAAiB,CAAC,OAAO,CAAC,CAAC,CAAC,EAAE,OAAO,KAAK,IAAI,CAAC,gBAAgB,CAAC,OAAO,CAAC,CAAC;;AAehF,IAAA,OAAO,CAAC,YAA2C,EAAA;AACjD,QAAA,MAAM,OAAO,GAAG,aAAa,CAAC,YAAY,CAAC;AAE3C,QAAA,OAAO,IAAI,UAAU,CAAC,CAAC,QAAoC,KAAI;YAC7D,MAAM,MAAM,GAAG,IAAI,CAAC,eAAe,CAAC,OAAO,CAAC;YAC5C,MAAM,YAAY,GAAG;AAClB,iBAAA,IAAI,CACH,GAAG,CAAC,OAAO,IAAI,OAAO,CAAC,MAAM,CAAC,MAAM,IAAI,CAAC,kBAAkB,CAAC,MAAM,CAAC,CAAC,CAAC,EACrE,MAAM,CAAC,OAAO,IAAI,CAAC,CAAC,OAAO,CAAC,MAAM,CAAC;iBAEpC,SAAS,CAAC,OAAO,IAAG;AACnB,gBAAA,IAAI,CAAC,OAAO,CAAC,GAAG,CAAC,MAAK;AACpB,oBAAA,QAAQ,CAAC,IAAI,CAAC,OAAO,CAAC;AACxB,iBAAC,CAAC;AACJ,aAAC,CAAC;AAEJ,YAAA,OAAO,MAAK;gBACV,YAAY,CAAC,WAAW,EAAE;AAC1B,gBAAA,IAAI,CAAC,iBAAiB,CAAC,OAAO,CAAC;AACjC,aAAC;AACH,SAAC,CAAC;;AAGJ;;;AAGG;AACK,IAAA,eAAe,CAAC,OAAgB,EAAA;AACtC,QAAA,OAAO,IAAI,CAAC,OAAO,CAAC,iBAAiB,CAAC,MAAK;YACzC,IAAI,CAAC,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAC,EAAE;AACxC,gBAAA,MAAM,MAAM,GAAG,IAAI,OAAO,EAAoB;AAC9C,gBAAA,MAAM,QAAQ,GAAG,IAAI,CAAC,wBAAwB,CAAC,MAAM,CAAC,SAAS,IAAI,MAAM,CAAC,IAAI,CAAC,SAAS,CAAC,CAAC;gBAC1F,IAAI,QAAQ,EAAE;AACZ,oBAAA,QAAQ,CAAC,OAAO,CAAC,OAAO,EAAE;AACxB,wBAAA,aAAa,EAAE,IAAI;AACnB,wBAAA,SAAS,EAAE,IAAI;AACf,wBAAA,OAAO,EAAE,IAAI;AACd,qBAAA,CAAC;;AAEJ,gBAAA,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,EAAE,EAAC,QAAQ,EAAE,MAAM,EAAE,KAAK,EAAE,CAAC,EAAC,CAAC;;iBAC5D;gBACL,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAE,CAAC,KAAK,EAAE;;YAE9C,OAAO,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAE,CAAC,MAAM;AACpD,SAAC,CAAC;;AAGJ;;;AAGG;AACK,IAAA,iBAAiB,CAAC,OAAgB,EAAA;QACxC,IAAI,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAC,EAAE;YACvC,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAE,CAAC,KAAK,EAAE;AAC5C,YAAA,IAAI,CAAC,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAE,CAAC,KAAK,EAAE;AAC/C,gBAAA,IAAI,CAAC,gBAAgB,CAAC,OAAO,CAAC;;;;;AAM5B,IAAA,gBAAgB,CAAC,OAAgB,EAAA;QACvC,IAAI,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAC,EAAE;AACvC,YAAA,MAAM,EAAC,QAAQ,EAAE,MAAM,EAAC,GAAG,IAAI,CAAC,iBAAiB,CAAC,GAAG,CAAC,OAAO,CAAE;YAC/D,IAAI,QAAQ,EAAE;gBACZ,QAAQ,CAAC,UAAU,EAAE;;YAEvB,MAAM,CAAC,QAAQ,EAAE;AACjB,YAAA,IAAI,CAAC,iBAAiB,CAAC,MAAM,CAAC,OAAO,CAAC;;;uGAtG/B,eAAe,EAAA,IAAA,EAAA,EAAA,EAAA,MAAA,EAAA,EAAA,CAAA,eAAA,CAAA,UAAA,EAAA,CAAA;AAAf,IAAA,OAAA,KAAA,GAAA,EAAA,CAAA,qBAAA,CAAA,EAAA,UAAA,EAAA,QAAA,EAAA,OAAA,EAAA,QAAA,EAAA,QAAA,EAAA,EAAA,EAAA,IAAA,EAAA,eAAe,cADH,MAAM,EAAA,CAAA;;2FAClB,eAAe,EAAA,UAAA,EAAA,CAAA;kBAD3B,UAAU;mBAAC,EAAC,UAAU,EAAE,MAAM,EAAC;;AA4GhC;;;AAGG;MAKU,iBAAiB,CAAA;AACpB,IAAA,gBAAgB,GAAG,MAAM,CAAC,eAAe,CAAC;AAC1C,IAAA,WAAW,GAAG,MAAM,CAA0B,UAAU,CAAC;;AAG3B,IAAA,KAAK,GAAG,IAAI,YAAY,EAAoB;AAElF;;;AAGG;AACH,IAAA,IACI,QAAQ,GAAA;QACV,OAAO,IAAI,CAAC,SAAS;;IAEvB,IAAI,QAAQ,CAAC,KAAc,EAAA;AACzB,QAAA,IAAI,CAAC,SAAS,GAAG,KAAK;AACtB,QAAA,IAAI,CAAC,SAAS,GAAG,IAAI,CAAC,YAAY,EAAE,GAAG,IAAI,CAAC,UAAU,EAAE;;IAElD,SAAS,GAAG,KAAK;;AAGzB,IAAA,IACI,QAAQ,GAAA;QACV,OAAO,IAAI,CAAC,SAAS;;IAEvB,IAAI,QAAQ,CAAC,KAAkB,EAAA;AAC7B,QAAA,IAAI,CAAC,SAAS,GAAG,oBAAoB,CAAC,KAAK,CAAC;QAC5C,IAAI,CAAC,UAAU,EAAE;;AAEX,IAAA,SAAS;IAET,oBAAoB,GAAwB,IAAI;AAGxD,IAAA,WAAA,GAAA;IAEA,kBAAkB,GAAA;QAChB,IAAI,CAAC,IAAI,CAAC,oBAAoB,IAAI,CAAC,IAAI,CAAC,QAAQ,EAAE;YAChD,IAAI,CAAC,UAAU,EAAE;;;IAIrB,WAAW,GAAA;QACT,IAAI,CAAC,YAAY,EAAE;;IAGb,UAAU,GAAA;QAChB,IAAI,CAAC,YAAY,EAAE;AACnB,QAAA,MAAM,MAAM,GAAG,IAAI,CAAC,gBAAgB,CAAC,OAAO,CAAC,IAAI,CAAC,WAAW,CAAC;AAE9D,QAAA,IAAI,CAAC,oBAAoB,GAAG,CAC1B,IAAI,CAAC,QAAQ,GAAG,MAAM,CAAC,IAAI,CAAC,YAAY,CAAC,IAAI,CAAC,QAAQ,CAAC,CAAC,GAAG,MAAM,EACjE,SAAS,CAAC,IAAI,CAAC,KAAK,CAAC;;IAGjB,YAAY,GAAA;AAClB,QAAA,IAAI,CAAC,oBAAoB,EAAE,WAAW,EAAE;;uGAzD/B,iBAAiB,EAAA,IAAA,EAAA,EAAA,EAAA,MAAA,EAAA,EAAA,CAAA,eAAA,CAAA,SAAA,EAAA,CAAA;AAAjB,IAAA,OAAA,IAAA,GAAA,EAAA,CAAA,oBAAA,CAAA,EAAA,UAAA,EAAA,QAAA,EAAA,OAAA,EAAA,QAAA,EAAA,IAAA,EAAA,iBAAiB,qHAW2B,gBAAgB,CAAA,EAAA,QAAA,EAAA,UAAA,EAAA,EAAA,OAAA,EAAA,EAAA,KAAA,EAAA,mBAAA,EAAA,EAAA,QAAA,EAAA,CAAA,mBAAA,CAAA,EAAA,QAAA,EAAA,EAAA,EAAA,CAAA;;2FAX5D,iBAAiB,EAAA,UAAA,EAAA,CAAA;kBAJ7B,SAAS;AAAC,YAAA,IAAA,EAAA,CAAA;AACT,oBAAA,QAAQ,EAAE,qBAAqB;AAC/B,oBAAA,QAAQ,EAAE,mBAAmB;AAC9B,iBAAA;wDAMuC,KAAK,EAAA,CAAA;sBAA1C,MAAM;uBAAC,mBAAmB;gBAOvB,QAAQ,EAAA,CAAA;sBADX,KAAK;AAAC,gBAAA,IAAA,EAAA,CAAA,EAAC,KAAK,EAAE,2BAA2B,EAAE,SAAS,EAAE,gBAAgB,EAAC;gBAYpE,QAAQ,EAAA,CAAA;sBADX;;MA4CU,eAAe,CAAA;uGAAf,eAAe,EAAA,IAAA,EAAA,EAAA,EAAA,MAAA,EAAA,EAAA,CAAA,eAAA,CAAA,QAAA,EAAA,CAAA;wGAAf,eAAe,EAAA,OAAA,EAAA,CAlEf,iBAAiB,CAAA,EAAA,OAAA,EAAA,CAAjB,iBAAiB,CAAA,EAAA,CAAA;wGAkEjB,eAAe,EAAA,SAAA,EAFf,CAAC,uBAAuB,CAAC,EAAA,CAAA;;2FAEzB,eAAe,EAAA,UAAA,EAAA,CAAA;kBAL3B,QAAQ;AAAC,YAAA,IAAA,EAAA,CAAA;oBACR,OAAO,EAAE,CAAC,iBAAiB,CAAC;oBAC5B,OAAO,EAAE,CAAC,iBAAiB,CAAC;oBAC5B,SAAS,EAAE,CAAC,uBAAuB,CAAC;AACrC,iBAAA;;;;;"}