_setUiSize(uiSize = this.options.uiSize) {
    const elementDimension = this._selectedElement.style;
    elementDimension.width = uiSize.width;
    elementDimension.height = uiSize.height;
  }
Set ui container size
@param {Object} uiSize - ui dimension
  @param {string} uiSize.width - css width property
  @param {string} uiSize.height - css height property
@private