import { ChangeDetectorRef, AfterViewInit } from "@angular/core";
import { NgControl, AbstractControl } from "@angular/forms";
import { MatFormFieldControl } from "@angular/material";
export declare abstract class CustomMatFormFieldNgControl extends NgControl {
    form?: AbstractControl;
}
export declare abstract class CustomMatFormFieldControl<T> extends MatFormFieldControl<T> {
    required: boolean;
    ngControl: CustomMatFormFieldNgControl;
}
export declare class MatFormFieldRequiredDirective implements AfterViewInit {
    private _cdRef;
    _control: CustomMatFormFieldControl<any>;
    constructor(_cdRef: ChangeDetectorRef);
    ngAfterViewInit(): void;
}