forked from MapComplete/MapComplete
27 lines
No EOL
821 B
TypeScript
27 lines
No EOL
821 B
TypeScript
import BaseUIElement from "../BaseUIElement";
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import {VariableUiElement} from "./VariableUIElement";
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import {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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UIEventSource.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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} |