type IframeMessageEvent<T> = MessageEvent<{
    data: T;
    method: string;
}>;
export declare class IframeMessageSwap {
    private iframeRef;
    private taskList;
    private listeners;
    setRef: (ref: HTMLIFrameElement) => void;
    postMessage: <T>(method: string, data?: T | undefined) => void;
    addListener: <T>(method: string, callback: (_data: T) => void) => {
        handleEvent: (event: IframeMessageEvent<T>) => void;
        off: () => void;
    };
    removeListener: <T>(handle: (event: IframeMessageEvent<T>) => void) => void;
    removeAllListeners: () => void;
}
export {};