forked from MapComplete/MapComplete
26 lines
821 B
TypeScript
26 lines
821 B
TypeScript
import BaseUIElement from "../BaseUIElement"
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import { VariableUiElement } from "./VariableUIElement"
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import { Stores, UIEventSource } from "../../Logic/UIEventSource"
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import Loading from "./Loading"
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export default class AsyncLazy extends BaseUIElement {
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private readonly _f: () => Promise<BaseUIElement>
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constructor(f: () => Promise<BaseUIElement>) {
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super()
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this._f = f
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}
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protected InnerConstructElement(): HTMLElement {
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// The caching of the BaseUIElement will guarantee that _f will only be called once
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return new VariableUiElement(
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Stores.FromPromise(this._f()).map((el) => {
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if (el === undefined) {
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return new Loading()
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}
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return el
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})
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).ConstructElement()
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}
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}
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