function activeColorChanged (ui, context) {
    if (isNullish(context) || (context !== colorBar && context !== colorMap)) positionMapAndBarArrows.call(that, ui, context)
    setTimeout(function () {
      updatePreview.call(that, ui)
      updateMapVisuals.call(that, ui)
      updateBarVisuals.call(that, ui)
    }, 0)
  }
Update color when user changes text values.
@param {external:jQuery} ui
@param {?module:jPicker.Slider} context
@returns {void}