import { h, Component, ComponentChildren } from 'preact';
type State = {
    isVisible: boolean;
};
type Props = {
    children: ComponentChildren;
    onVisibleChange?: (isVisible: boolean) => void;
    className?: string;
};
declare class Observer extends Component<Props, State> {
    io: any;
    container: HTMLElement | null;
    componentDidMount(): void;
    componentWillUnmount(): void;
    render({ children, className }: Props, { isVisible }: State): h.JSX.Element;
}
export default Observer;