Feature Label MinScale Issue

LloydBronn · ‎04-24-2017

I'm trying to have my feature layer labels show up at a certain zoom level. I can set maxScale and get results, but minScale doesn't work.

var labelColor = new Color("#00F");
          var font = new Font();
          font.setFamily("arial");
          font.setSize("10pt");
          
          var textSymbol = new TextSymbol();
        textSymbol.setFont(font);
          
          var basin = "{Name}";
    
        var json = {
          "labelExpressionInfo": {"value": basin + " Basin"},
            "minScale":3
        };

        
        var labelClass = new LabelClass(json);
        labelClass.symbol = textSymbol;
        waterbasins.setLabelingInfo([ labelClass ]);‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

RobertScheitlin__GISP · ‎04-25-2017

Lloyd,

Using this sample you have to zoom in three levels before the label will show:

<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <meta name="viewport" content="initial-scale=1, maximum-scale=1, user-scalable=no">
    <title>Labeling features client-side</title>
    <link rel="stylesheet" href="https://js.arcgis.com/3.20/esri/css/esri.css">
    <style>
      html, body, #map {
        height: 100%; width: 100%; margin: 0; padding: 0; 
      }
    </style>

   <script src="https://js.arcgis.com/3.20/"></script>
    <script>
      var map;
    
      require([
        "esri/map", 
        "esri/geometry/Extent",
        "esri/layers/FeatureLayer",
        "esri/symbols/SimpleLineSymbol",
        "esri/symbols/SimpleFillSymbol",
        "esri/symbols/TextSymbol",
        "esri/renderers/SimpleRenderer",
        "esri/layers/LabelClass",
        "esri/Color",
         
        "dojo/domReady!"
      ], function(Map, Extent, FeatureLayer,
                  SimpleLineSymbol, SimpleFillSymbol, 
                  TextSymbol, SimpleRenderer, LabelClass, Color) 
      {
        // load the map centered on the United States
        var bbox = new Extent({"xmin": -1940058, "ymin": -814715, "xmax": 1683105, "ymax": 1446096, "spatialReference": {"wkid": 102003}});
      
        //create the map and set the extent, making sure to "showLabels"
        map = new Map("map", {
          extent: bbox,
          showLabels : true //very important that this must be set to true!   
        });

        // create a renderer for the states layer to override default symbology
        var statesColor = new Color("#666");
        var statesLine = new SimpleLineSymbol("solid", statesColor, 1.5);
        var statesSymbol = new SimpleFillSymbol("solid", statesLine, null);
        var statesRenderer = new SimpleRenderer(statesSymbol);
         
        // create the feature layer to render and label
        var statesUrl = "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer/3";
        var states = new FeatureLayer(statesUrl, {
          id: "states",
          outFields: ["*"]
        });
        states.setRenderer(statesRenderer);


        // create a text symbol to define the style of labels
        var statesLabel = new TextSymbol().setColor(statesColor);
        statesLabel.font.setSize("14pt");
        statesLabel.font.setFamily("arial");

        //this is the very least of what should be set within the JSON  
        var json = {
          "labelExpressionInfo": {"value": "{STATE_NAME}"},
          "minScale": 5000000
        };

        //create instance of LabelClass (note: multiple LabelClasses can be passed in as an array)
        var labelClass = new LabelClass(json);
        labelClass.symbol = statesLabel; // symbol also can be set in LabelClass' json
        states.setLabelingInfo([ labelClass ]);
        map.addLayer(states);
    
      });
    </script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

View solution in original post

RobertScheitlin__GISP · ‎04-24-2017

Lloyd,

Zoom Level and Zoom Scale are two different animals a map may have zoom levels like 1 through 21 where valid zoom scale could be 500 through 300,000. So a minScale of 3 is a very unlikely value.

LloydBronn · ‎04-24-2017

OK. I tried setting the minScale at various points between 500 to 300,000 and the labels aren't showing up at any zoom level.

RobertScheitlin__GISP · ‎04-24-2017

Lloyd,

Hmm. Normally a label expression looks like this:

"labelExpressionInfo": {"value": "{SomeFieldName}"},

LloydBronn · ‎04-25-2017

Should I even be setting the minScale under the json variable after the label expression? I've tried setting it as labelClass.minScale = 7999; which is zoom level 4 according to this example. The labels still aren't showing up. Do I have to have a maxScale in addition to minScale?

       var json = {
          "labelExpressionInfo": {"value": basin + " Basin"},
        }; 
          

        
        var labelClass = new LabelClass(json);
          //labelClass.maxScale =;
          labelClass.minScale = 7999;
        labelClass.symbol = textSymbol;
        waterbasins.setLabelingInfo([ labelClass ]);‍‍‍‍‍‍‍‍‍‍‍

RobertScheitlin__GISP · ‎04-25-2017

Lloyd,

Have you tried not using either min or max scale just to test if your using label class correctly?

LloydBronn · ‎04-25-2017

Yes, the labels show up fine without scale settings. The only thing that has worked is when I set maxScale to 3 or 4. The labels disappear at those zoom levels. That shouldn't work based on what you said before.

RobertScheitlin__GISP · ‎04-25-2017

Lloyd,

Using this sample you have to zoom in three levels before the label will show:

<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <meta name="viewport" content="initial-scale=1, maximum-scale=1, user-scalable=no">
    <title>Labeling features client-side</title>
    <link rel="stylesheet" href="https://js.arcgis.com/3.20/esri/css/esri.css">
    <style>
      html, body, #map {
        height: 100%; width: 100%; margin: 0; padding: 0; 
      }
    </style>

   <script src="https://js.arcgis.com/3.20/"></script>
    <script>
      var map;
    
      require([
        "esri/map", 
        "esri/geometry/Extent",
        "esri/layers/FeatureLayer",
        "esri/symbols/SimpleLineSymbol",
        "esri/symbols/SimpleFillSymbol",
        "esri/symbols/TextSymbol",
        "esri/renderers/SimpleRenderer",
        "esri/layers/LabelClass",
        "esri/Color",
         
        "dojo/domReady!"
      ], function(Map, Extent, FeatureLayer,
                  SimpleLineSymbol, SimpleFillSymbol, 
                  TextSymbol, SimpleRenderer, LabelClass, Color) 
      {
        // load the map centered on the United States
        var bbox = new Extent({"xmin": -1940058, "ymin": -814715, "xmax": 1683105, "ymax": 1446096, "spatialReference": {"wkid": 102003}});
      
        //create the map and set the extent, making sure to "showLabels"
        map = new Map("map", {
          extent: bbox,
          showLabels : true //very important that this must be set to true!   
        });

        // create a renderer for the states layer to override default symbology
        var statesColor = new Color("#666");
        var statesLine = new SimpleLineSymbol("solid", statesColor, 1.5);
        var statesSymbol = new SimpleFillSymbol("solid", statesLine, null);
        var statesRenderer = new SimpleRenderer(statesSymbol);
         
        // create the feature layer to render and label
        var statesUrl = "https://sampleserver6.arcgisonline.com/arcgis/rest/services/Census/MapServer/3";
        var states = new FeatureLayer(statesUrl, {
          id: "states",
          outFields: ["*"]
        });
        states.setRenderer(statesRenderer);


        // create a text symbol to define the style of labels
        var statesLabel = new TextSymbol().setColor(statesColor);
        statesLabel.font.setSize("14pt");
        statesLabel.font.setFamily("arial");

        //this is the very least of what should be set within the JSON  
        var json = {
          "labelExpressionInfo": {"value": "{STATE_NAME}"},
          "minScale": 5000000
        };

        //create instance of LabelClass (note: multiple LabelClasses can be passed in as an array)
        var labelClass = new LabelClass(json);
        labelClass.symbol = statesLabel; // symbol also can be set in LabelClass' json
        states.setLabelingInfo([ labelClass ]);
        map.addLayer(states);
    
      });
    </script>
  </head>
  <body>
    <div id="map"></div>
  </body>
</html>‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

LloydBronn · ‎04-25-2017

Still no labels at any zoom level if I set a minScale.

RobertScheitlin__GISP · ‎04-25-2017

The sample I provided works fine for me did you test it?