setLink() {
  // getting url from prompt dialogue
  const urlValue = prompt('Введите ссылку', '');
  // getting current editor state
  const { editorState } = this.state;
  // getting current contentState
  const contentState = editorState.getCurrentContent();
  // creating Entity
  const contentStateWithEntity = contentState.createEntity(
    'LINK',
    'SEGMENTED',
    { url: urlValue }
  );
  const entityKey = contentStateWithEntity.getLastCreatedEntityKey();
  // updating currentContent property in editorState
  const newEditorState = EditorState.set(editorState, {currentContent: contentStateWithEntity});

  // generating and saving new editor state
  this.setState({
    editorState: RichUtils.toggleLink(
      newEditorState,
      newEditorState.getSelection(),
      entityKey
    )
  }, () => {
    setTimeout(() => this.focus(), 0);
  });
}