/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
import { Observable } from 'rxjs';
import { NgControl } from '@angular/forms';
/** An interface which allows a control to work inside of a `MatFormField`. */
export declare abstract class MatFormFieldControl<T> {
    /** The value of the control. */
    value: T | null;
    /**
     * Stream that emits whenever the state of the control changes such that the parent `MatFormField`
     * needs to run change detection.
     */
    readonly stateChanges: Observable<void>;
    /** The element ID for this control. */
    readonly id: string;
    /** The placeholder for this control. */
    readonly placeholder: string;
    /** Gets the NgControl for this control. */
    readonly ngControl: NgControl | null;
    /** Whether the control is focused. */
    readonly focused: boolean;
    /** Whether the control is empty. */
    readonly empty: boolean;
    /** Whether the `MatFormField` label should try to float. */
    readonly shouldLabelFloat: boolean;
    /** Whether the control is required. */
    readonly required: boolean;
    /** Whether the control is disabled. */
    readonly disabled: boolean;
    /** Whether the control is in an error state. */
    readonly errorState: boolean;
    /**
     * An optional name for the control type that can be used to distinguish `mat-form-field` elements
     * based on their control type. The form field will add a class,
     * `mat-form-field-type-{{controlType}}` to its root element.
     */
    readonly controlType?: string;
    /**
     * Whether the input is currently in an autofilled state. If property is not present on the
     * control it is assumed to be false.
     */
    readonly autofilled?: boolean;
    /**
     * Value of `aria-describedby` that should be merged with the described-by ids
     * which are set by the form-field.
     */
    readonly userAriaDescribedBy?: string;
    /** Sets the list of element IDs that currently describe this control. */
    abstract setDescribedByIds(ids: string[]): void;
    /** Handles a click on the control's container. */
    abstract onContainerClick(event: MouseEvent): void;
}