This sample demonstrates how to query related features from a FeatureLayer by using the queryRelatedFeatures() method. Each hexagon on the map represents one or more major cities in the U.S. Clicking on a hexagon will trigger a query for its related features, which will be displayed in a table added to the view's UI.
How it works
A function calls queryObjectIds() whenever the user clicks on the map, which returns the objectId of the corresponding hexagon in the layer.
We get the attributes from the resulting FeatureSet and create a dgrid component that can hold the resulting data.
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// get the attributes of the FeatureSetconst rows = relatedFeatureSet.features.map(function(feature) {
return feature.attributes;
});
if (!rows.length) { return; }
// create a new div for the grid of related features// append to queryResults div inside of the Feature widgetconst gridDiv = document.createElement("div")
const results = document.getElementById("queryResults");
results.appendChild(gridDiv);
// destroy current grid if existsif (grid) {
grid.destroy();
}
// create the grid to hold the results of the query grid = new Grid({
columns: Object.keys(rows[0]).map(function(fieldName) {
return {
label: fieldName,
field: fieldName,
sortable: true };
})
}, gridDiv);
// add the data to the grid grid.renderArray(rows);