MapImageLayer - 从动态工作区探索数据

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// Get the sublayer to explore
const ancestrySublayer = layer.sublayers.find((sublayer) => {
  return sublayer.title === "% population with selected ancestry";
});

ancestrySublayer.createFeatureLayer().then((ancestryFeatureLayer) => {
  // use the feature layer instance for some other purpose,
  // such as generating a renderer
});

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const params = {
  // set FeatureLayer as input
  layer: ancestryFeatureLayer,
  // Arcade is used to normalize and round the data
  valueExpression: "Round( ( $feature['" + ancestrySelect.value + "'] / $feature['states.POP2007'] ) * 100, 1);",
  view: view, // required with valueExpression
  classificationMethod: classSelect.value
};

colorRendererCreator.createClassBreaksRenderer(params).then((response) => {
  // set the renderer on the sublayer
  ancestrySublayer.renderer = response.renderer;
});

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// Set LayerList with two content elements in the same panel
// 1. A div element containing the select elements for data exploration
// 2. a legend instance
const layerList = new LayerList({
  view: view,
  listItemCreatedFunction: (event) => {
    const item = event.item;
    item.panel = {
      content: [document.getElementById("infoDiv"), "legend"],
      open: true
    };
  }
});
view.ui.add(layerList, "top-right");