import { EventEmitter, NgZone } from '@angular/core';
import { MatSelect } from '@angular/material/select';
import * as i0 from "@angular/core";
export declare class NgxLazyMatSelectDirective {
    private matSelect;
    private ngZone;
    threshold: string;
    debounceTime: number;
    complete: boolean;
    infiniteScroll: EventEmitter<void>;
    private panel;
    private thrPx;
    private thrPc;
    private singleOptionHeight;
    private destroyed$;
    constructor(matSelect: MatSelect, ngZone: NgZone);
    ngOnInit(): void;
    ngAfterViewInit(): void;
    ngOnDestroy(): void;
    evaluateThreshold(): void;
    registerScrollListener(): void;
    handleScrollEvent(event: any): void;
    getSelectItemHeightPx(): number;
    static ɵfac: i0.ɵɵFactoryDeclaration<NgxLazyMatSelectDirective, never>;
    static ɵdir: i0.ɵɵDirectiveDeclaration<NgxLazyMatSelectDirective, "[ngxLazyMatSelect]", never, { "threshold": { "alias": "threshold"; "required": false; }; "debounceTime": { "alias": "debounceTime"; "required": false; }; "complete": { "alias": "complete"; "required": false; }; }, { "infiniteScroll": "infiniteScroll"; }, never, never, false, never>;
}