Style data feature examples

This page shows how to programmatically access a dataset and style its features, and walks through styling examples for data features based on point, polygon, and polyline geometries.

Data-driven styling for datasets renders data features based on the provided latitude and longitude coordinates from the geospatial data file used to create the dataset.

Point data styling example

This example shows an approach to styling point geometry based data features.

Apply styling to features representing squirrel colors.

About the dataset

The dataset used in this example is the result of a 2018 survey of squirrels in Central Park, New York City. In the following excerpt from the CSV data file, we see that columns x and y are used for geography; a LatLng column is included, but it's not used in this example because datasets only support the WKT format if the column is named WKT. For more information about the supported formats for location, see CSV requirements.

The squirrel census dataset contains a nice variety of different data points relating to the observed fur color and behavior of squirrels (be sure to scroll horizontally to see it all).

X Y UniqueSquirrelID Hectare Shift Date Hectare SquirrelNumber Age PrimaryFurColor HighlightFurColor CombinationofPrimaryandHighlightColor Colornotes Location AboveGroundSighter Measurement SpecificLocation Running Chasing Climbing Eating Foraging Other Activities Kuks Quaas Moans Tailflags Tailtwitches Approaches Indifferent Runsfrom OtherInteractions LatLng
-73.9561344937861 40.7940823884086 37F-PM-1014-03 37F PM 10142018 3 + false false false false false false false false false false false false false POINT (-73.9561344937861 40.7940823884086)
-73.9688574691102 40.7837825208444 21B-AM-1019-04 21B AM 10192018 4 + false false false false false false false false false false false false false POINT (-73.9688574691102 40.7837825208444)
-73.9742811484852 40.775533619083 11B-PM-1014-08 11B PM 10142018 8 Gray Gray+ Above Ground 10 false true false false false false false false false false false false false POINT (-73.97428114848522 40.775533619083)
-73.9596413903948 40.7903128889029 32E-PM-1017-14 32E PM 10172018 14 Adult Gray Gray+ Nothing selected as Primary. Gray selected as Highlights. Made executive adjustments. false false false true true false false false false false false false true POINT (-73.9596413903948 40.7903128889029)
-73.9702676472613 40.7762126854894 13E-AM-1017-05 13E AM 10172018 5 Adult Gray Cinnamon Gray+Cinnamon Above Ground on tree stump false false false false true false false false false false false false false POINT (-73.9702676472613 40.7762126854894)
-73.9683613516225 40.7725908847499 11H-AM-1010-03 11H AM 10102018 3 Adult Cinnamon White Cinnamon+White false false false false true false false false false true false true false POINT (-73.9683613516225 40.7725908847499)
-73.9541201789795 40.7931811701082 36H-AM-1010-02 36H AM 10102018 2 Adult Gray Gray+ just outside hectare Ground Plane FALSE false false false false true false false false false false false false false POINT (-73.9541201789795 40.7931811701082)

Style point data features

The code in this example takes the approach of styling the fill color and stroke color for each point based on the CombinationofPrimaryandHighlightColor attribute, which combines the primary and secondary fur colors for each squirrel.

Swift

let mapView = GMSMapView(frame: .zero, mapID: GMSMapID(identifier: "YOUR_MAP_ID"), camera: GMSCameraPosition(latitude: 20.773, longitude: -156.01, zoom: 12))

let layer = mapView.datasetFeatureLayer(of: "YOUR_DATASET_ID")

// Define a point style with fill and radius.
// Apply the style to the datasets features.
layer.style = { feature in
    switch(feature.datasetAttributes["CombinationofPrimaryandHighlightColor"]){
      case "Black+"  :
        let style = MutableFeatureStyle()
        style.fillColor = .black;
        style.pointRadius = 8;
        return style
      case "Cinnamon+"  :
        let style = MutableFeatureStyle()
        style.fillColor = UIColor(red: 139/255, green: 0, blue: 0, alpha: 1);
        style.pointRadius = 8;
        return style
      ...
      default :
        let style = MutableFeatureStyle()
        style.fillColor = .yellow;
        style.pointRadius = 8;
        return style
    }
}

Objective-C

GMSMapView *mapView = [GMSMapView mapWithFrame:CGRectZero mapID:[GMSMapID mapIDWithIdentifier:@"MAP_ID"] camera:[GMSCameraPosition cameraWithLatitude: 20.773 longitude: -156.01 zoom:12]];

GMSFeatureLayer<GMSDatasetFeature *> *layer = [mapView featureLayerOfFeatureType:GMSFeatureTypeDataset];

// Define a point style with fill and radius.
// Apply the style to the datasets features.
layer.style = ^(GMSDatasetFeature *feature) {
    switch(feature.datasetAttributes[@"CombinationofPrimaryandHighlightColor"]){
      case 'Black+'  :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [UIColor blackColor];
        style.pointRadius = 8;
        return style;
      case 'Cinnamon+'  :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [UIColor colorWithRed:139.0f/255.0f
          green:0.0f
          blue:0.0f
          alpha:1.0f];
        style.pointRadius = 8;
        return style;
      ...
      default :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [UIColor yellowColor];
        style.pointRadius = 8;
        return style;
    }
};

Polygon data styling example

This example shows an approach to styling polygon geometry based data features.

Apply styling to features representing park types.

About the dataset

The dataset used in this example depicts parks in New York City. The following excerpt from the dataset GeoJSON file shows a representative feature entry.

{
  "type": "Feature",
  "properties": {
    "jurisdiction": "DPR",
    "mapped": "False",
    "zipcode": "11356",
    "acres": "0.05",
    "location": "College Pl., College Pt. Blvd., bet. 11 Ave. and 12 Ave.",
    "nys_assembly": "27",
    "councildistrict": "19",
    "url": "http://www.nycgovparks.org/parks/Q042/",
    "typecategory": "Triangle/Plaza",
    "us_congress": "14",
    "eapply": "Poppenhusen Park",
    "parentid": "Q-07",
    "gispropnum": "Q042",
    "retired": "false",
    "communityboard": "407",
    "objectid": "6248",
    "globalid": "F4810079-CBB9-4BE7-BBFA-B3C0C35D5DE5",
    "name311": "Poppenhusen Park",
    "department": "Q-07",
    "pip_ratable": "true",
    "subcategory": "Sitting Area/Triangle/Mall",
    "precinct": "109",
    "permit": "true",
    "acquisitiondate": null,
    "omppropid": "Q042",
    "gisobjid": "100000301",
    "signname": "Poppenhusen Park",
    "address": null,
    "permitparent": "Q-07",
    "class": "PARK",
    "nys_senate": "11",
    "permitdistrict": "Q-07",
    "borough": "Q",
    "waterfront": "false"
  },
  "geometry": {
    "type": "MultiPolygon",
    "coordinates": [
      [
        [
          [
            -73.84575702371716,
            40.78796240884273
          ],
          [
            -73.84593393292693,
            40.78796857347548
          ],
          [
            -73.84577256469657,
            40.787651355629556
          ],
          [
            -73.84575702371716,
            40.78796240884273
          ]
        ]
      ]
    ]
  }
},

Style polygon data features

The code in this example applies special coloring to data features associated with a typecategory of "Undeveloped" or "Parkway", and colors all other features green.

Swift

let mapView = GMSMapView(frame: .zero, mapID: GMSMapID(identifier: "YOUR_MAP_ID"), camera: GMSCameraPosition(latitude: 20.773, longitude: -156.01, zoom: 12))

let layer = mapView.datasetFeatureLayer(of: "YOUR_DATASET_ID")

// Define a polygon style with fill and stroke.
// Apply the style to the datasets features.
layer.style = { feature in
    switch(feature.datasetAttributes["typecategory"]){
      case "Undeveloped"  :
        let style = MutableFeatureStyle()
        style.fillColor = .blue.withAlphaComponent(0.3);
        style.strokeColor = .blue
        style.strokeWidth = 2.0;
        return style
      case "Parkway"  :
        let style = MutableFeatureStyle()
        style.fillColor = .red.withAlphaComponent(0.3);
        style.strokeColor = .red
        style.strokeWidth = 2.0;
        return style
      default :
        let style = MutableFeatureStyle()
        style.fillColor = .green.withAlphaComponent(0.3);
        style.strokeColor = .green
        style.strokeWidth = 2.0;
        return style
    }
}

Objective-C

GMSMapView *mapView = [GMSMapView mapWithFrame:CGRectZero mapID:[GMSMapID mapIDWithIdentifier:@"MAP_ID"] camera:[GMSCameraPosition cameraWithLatitude: 20.773 longitude: -156.01 zoom:12]];

GMSFeatureLayer<GMSDatasetFeature *> *layer = [mapView featureLayerOfFeatureType:GMSFeatureTypeDataset];

// Define a polygon style with fill and stroke.
// Apply the style to the datasets features.
layer.style = ^(GMSDatasetFeature *feature) {
    switch(feature.datasetAttributes[@"typecategory"]){
      case 'Undeveloped'  :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [[UIColor blueColor] colorWithAlphaComponent:0.3];
        style.strokeColor = [UIColor blueColor];
        style.strokeWidth = 2.0;
        return style;
      case 'Parkway'  :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [[UIColor redColor] colorWithAlphaComponent:0.3];
        style.strokeColor = [UIColor redColor];
        style.strokeWidth = 2.0;
        return style;
      default :
        GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
        style.fillColor = [[UIColor greenColor] colorWithAlphaComponent:0.3];
        style.strokeColor = [UIColor greenColor];
        style.strokeWidth = 2.0;
        return style;
    }
};

Polyline data styling example

This example shows an approach to styling polyline geometry based data features.

Apply styling to features that represent polylines.

About the dataset

The dataset used in this example shows bridges in the Seattle area. The following excerpt from the dataset GeoJSON file shows a representative feature entry.

{
  "type": "Feature",
  "properties": {
      "OBJECTID": 1,
      "COMPTYPE": 66,
      "COMPKEY": 515774,
      "HANSEGKEY": 489781,
      "UNITID": "BRG-935",
      "UNITTYPE": " ",
      "BRGUNITID": "BRG-935",
      "UNITDESC_BRG": "YALE AVE BR REV LANE OC                                                                                                                                                                                                                                        ",
      "UNITDESC_SEG": "HOWELL ST ON RP BETWEEN HOWELL ST AND I5 SB                                                                                                                                                                                                                    ",
      "INSTDATE": null,
      "EXPDATE": null,
      "STATUS": " ",
      "STATUSDT": null,
      "CONDITION": " ",
      "CONDDT": null,
      "OWN": " ",
      "LSTVERIFY": null,
      "MAINTBY": " ",
      "ADDBY": "GARCIAA",
      "ADDDTTM": "2010-01-21T00:00:00Z",
      "MODBY": null,
      "MODDTTM": null,
      "BR_NBR": 935,
      "BR_CODE": " 935",
      "BR_TYPE": "ST",
      "BR_NAME": "YALE AVE BR REV LANE OC",
      "BR_FACILITIES": "YALE AVE-SR 5 ON RAMP",
      "BR_FEATURES": "SR 5 REV LANE",
      "BR_RATING": 0,
      "BR_INSET": 1,
      "BR_GEO": "DT",
      "BR_OWNER": "DOT",
      "BR_OWNER_NAME": "State of Washington",
      "GEOBASID": 0,
      "XGEOBASID": 0,
      "GISSEGKEY": 489781,
      "EARTHQUAKE_RESPONSE_TEAM": " ",
      "SHAPE_Length": 220.11891836147655
  },
  "geometry": {
      "type": "LineString",
      "coordinates": [
          [
              -122.329201929090928,
              47.616910448708538
          ],
          [
              -122.329206483407461,
              47.616976719821004
          ],
          [
              -122.32921802149356,
              47.617042137515213
          ],
          [
              -122.329236413912909,
              47.617105967923777
          ],
          [
              -122.329261454336034,
              47.617167494985758
          ],
          [
              -122.329292861855023,
              47.617226028479571
          ],
          [
              -122.329330284134699,
              47.617280911766009
          ],
          [
              -122.329373301365223,
              47.617331529154569
          ],
          [
              -122.329421430971635,
              47.617377312810319
          ],
          [
              -122.329474133027375,
              47.617417749124023
          ],
          [
              -122.32953081631139,
              47.617452384473893
          ]
      ]
  }
},

Style polyline data features

The following snippet applies the same style to directly to all data features.

Swift

// Define a style with green fill and stroke.
// Apply the style to the datasets features.
layer.style = { feature in
    let style = MutableFeatureStyle()
    style.fillColor = .green.withAlphaComponent(0.5);
    style.strokeColor = [UIColor greenColor];
    style.strokeWidth = 2.0;
    return style
}

Objective-C

// Define a style with green fill and stroke.
// Apply the style to the datasets features.
layer.style = ^(GMSDatasetFeature *feature) {
    GMSMutableFeatureStyle *style = [GMSMutableFeatureStyle style];
    style.fillColor = [[UIColor greenColor] colorWithAlphaComponent:0.5];
    style.strokeColor = [UIColor greenColor];
    style.strokeWidth = 2.0;
    return style;
};