import * as React from 'react';
import { ExtensionsProps } from '../context';
import { ErrorLike } from '../errors';
import { ConfigurationSubject, ConfiguredSubjectOrError, Settings } from '../settings';
import { ConfiguredExtension } from './extension';
declare const LOADING: 'loading';
interface Props<S extends ConfigurationSubject, C extends Settings> extends ExtensionsProps<S, C> {
    /** The extension that this button adds. */
    extension: ConfiguredExtension;
    /** The configuration subject that this button adds the extension for. */
    subject: ConfiguredSubjectOrError<ConfigurationSubject, Settings>;
    disabled?: boolean;
    className?: string;
    /**
     * Called to confirm the primary action. If the callback returns false, the action is not
     * performed.
     */
    confirm?: () => boolean;
    /** Called when the component performs an update that requires the parent component to refresh data. */
    onUpdate: () => void;
}
interface State {
    /** The operation's status: null when done or not started, 'loading', or an error. */
    operationResultOrError: typeof LOADING | null | ErrorLike;
}
/** An button to add an extension. */
export declare class ExtensionAddButton<S extends ConfigurationSubject, C extends Settings> extends React.PureComponent<Props<S, C>, State> {
    state: State;
    private clicks;
    private subscriptions;
    componentDidMount(): void;
    componentWillUnmount(): void;
    render(): JSX.Element | null;
    private onClick;
    private addExtensionForSubject;
}
export {};