参考 PopupTemplate 中的 Arcade 表达式

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<script type="text/plain" id="predominance-arcade">
  // The fields from which to calculate predominance
  // The expression will return the alias of the predominant field

  var fields = [
    { value: $feature.NOT_LABORFORCE_16, alias: "NOT participating in the labor force" },
    { value: $feature.CIVLBFR_CY, alias: "participating in labor the force" }
  ];

  // Returns the predominant category as the alias
  // defined in the fields array. If there is a tie,
  // then both names are concatenated and used to
  // indicate the tie

  function getPredominantCategory(fieldsArray){
    var maxValue = -Infinity;
    var maxCategory = "";
    for(var k in fieldsArray){
      if(fieldsArray[k].value > maxValue){
        maxValue = fieldsArray[k].value;
        maxCategory = fieldsArray[k].alias;
      } else if (fieldsArray[k].value == maxValue){
        maxCategory = maxCategory + "/" + fieldsArray[k].alias;
      }
    }
    return maxCategory;
  }

  getPredominantCategory(fields);
</script>

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<script type="text/plain" id="strength-arcade">
  // Returns the share of the dominant demographic as a percentage
  var fieldValues = [ $feature.NOT_LABORFORCE_16, $feature.CIVLBFR_CY ];
  var winner = Max(fieldValues);
  var total = Sum(fieldValues);
  return (winner/total) * 100;
</script>

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$feature.POP_16UP - $feature.EMP_CY;

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Round((($feature.POP_16UP - $feature.EMP_CY) / $feature.POP_16UP) * 100) + "%";

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const arcadeExpressionInfos = [
  {
    name: "predominance-arcade",
    title: "Is the majority (>50%) of the population 16+ participating in the labor force?",
    // defined in separate script element
    expression: document.getElementById("predominance-arcade").text
  },
  {
    name: "strength-arcade",
    title: "% of population belonging to majority category",
    // defined in separate script element
    expression: document.getElementById("strength-arcade").text
  },
  {
    name: "not-working-arcade",
    title: "Total population 16+ not employed or in labor force",
    expression: "$feature.POP_16UP - $feature.EMP_CY"
  },
  {
    name: "%-not-working-arcade",
    title: "% of population 16+ not employed or in labor force",
    expression: "Round((($feature.POP_16UP - $feature.EMP_CY)/$feature.POP_16UP)*100,2) + '%'"
  }
];

popupTemplate.expressionInfos = arcadeExpressionInfos;

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popupTemplate.content = [
  {
    type: "text",
    text:
      "In this county, {UNEMPRT_CY}% of the labor force is unemployed. " +
      " {expression/strength-arcade}% of the {POP_16UP} people ages 16+" +
      " living here are {expression/predominance-arcade}."
  },
  {
    type: "fields",
    fieldInfos: [
      {
        fieldName: "expression/not-working-arcade",
        format: {
          digitSeparator: true,
          places: 0
        }
      },
      {
        fieldName: "expression/%-not-working-arcade",
        format: {
          digitSeparator: true,
          places: 0
        }
      }
    ]
  }
];