// Create a MapImageLayer instance pointing to a Map Service
      // containing data about US Cities, Counties, States and Highways.
      // Define sublayers with visibility for each layer in Map Service.
      // Set an initial definition expression on the cities sublayer.
      const layer = new MapImageLayer({
        url: "https://sampleserver6.arcgisonline.com/arcgis/rest/services/USA/MapServer",
        sublayers: [
          {
            id: 3,
            visible: false,
          },
          {
            id: 2,
            visible: true,
          },
          {
            id: 1,
            visible: true,
          },
          {
            id: 0,
            visible: true,
            definitionExpression: "pop2000 > 100000",
          },
        ],
      });

      // Add event listener for when the slider thumb is released
      // and set the definition expression on the cities sublayer.
      slider.addEventListener("calciteSliderChange", () => {
        selectedPopulation = Number(slider.value);
        citiesSublayer.definitionExpression = `pop2000 > ${selectedPopulation}`;
      });

      // Add event listener for when the slider input changes during sliding
      // and update the text showing the current population value.
      slider.addEventListener("calciteSliderInput", () => {
        sliderCount.textContent = slider.value;
      });