Style a feature layer

Learn how to apply renderers and label definitions to a feature layer based on attribute values.

Applications can display feature layer data with different styles to enhance the visualization. The type of Renderer you choose depends on your application. A SimpleRenderer applies the same symbol to all features, a UniqueValueRenderer applies a different symbol to each unique attribute value, and a ClassBreaksRenderer applies a symbol to a range of numeric values. Renderers are responsible for accessing the data and applying the appropriate symbol to each feature when the layer draws. You can also use a LabelDefinition to show attribute information for features. Visit the Styles and data visualization documentation to learn more about styling layers.

You can also author, style and save web maps, web scenes, and layers as portal items and then add them to the map in your application. Visit the following tutorials to learn more about adding portal items.

In this tutorial, you will apply different renderers to enhance the visualization of three feature layers with data for the Santa Monica Mountains: Trailheads with a single symbol, Trails based on elevation change and bike use, and Parks and Open Spaces based on the type of park.

Prerequisites

The following are required for this tutorial:

An ArcGIS account to access API keys. If you don't have an account, sign up for free.
A development and deployment environment that meets the system requirements.
An IDE for Android development in Kotlin.

Steps

To start this tutorial, complete the Display a map tutorial. Or download and unzip the Display a map solution in a new folder.

Modify the old project for use in this new tutorial. Expand More info for instructions.

On your file system, delete the .idea folder, if present, at the top level of your project.
In the Android tool window, open app > res > values > strings.xml.

In the <string name="app_name"> element, change the text content to Style a feature layer.
strings.xml
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1 2 3 <resources> <string name="app_name">Style a feature layer</string> </resources>

In the Android tool window, open Gradle Scripts > settings.gradle.kts.

Change the value of rootProject.name to "Style a feature layer".

settings.gradle.kts
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dependencyResolutionManagement {
    @Suppress("UnstableApiUsage")
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    @Suppress("UnstableApiUsage")
    repositories {
        google()
        mavenCentral()
        maven { url = uri("https://esri.jfrog.io/artifactory/arcgis") }
    }
}

rootProject.name = "Style a feature layer"
include(":app")

The UI theme composable in Display a map tutorial was DisplayAMapTheme. Rename the theme composable throughout the tutorial by refactoring DisplayAMapTheme.

In the Android tool window, open app > kotlin+java > com.exmple.app > ui.theme > Theme.kt.

Right-click the function name DisplayAMapTheme and select Refactor -> Rename. Replace the name with StyleAFeatureLayerTheme.

Theme.kt
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@Composable
fun DisplayAMapTheme(

    darkTheme: Boolean = isSystemInDarkTheme(),
    // Dynamic color is available on Android 12+
    dynamicColor: Boolean = true,
    content: @Composable () -> Unit
) {
    val colorScheme = when {
        dynamicColor && Build.VERSION.SDK_INT >= Build.VERSION_CODES.S -> {
            val context = LocalContext.current
            if (darkTheme) dynamicDarkColorScheme(context) else dynamicLightColorScheme(context)
        }

        darkTheme -> DarkColorScheme
        else -> LightColorScheme
    }

Click File > Sync Project with Gradle files. Android Studio will recognize your changes and create a new .idea folder.

Set your API key in MainActivity.kt.
An API Key enables access to services, web maps, and web scenes hosted in ArcGIS Online.
1. In Android Studio: in the Android tool window, open app > java > com.example.app > MainActivity.
2. In the setApiKey() function, find the ApiKey.create() call and paste your API key inside the quotes, replacing YOUR_API_KEY.
  MainActivity.kt
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  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 private fun setApiKey() { ArcGISEnvironment.apiKey = ApiKey.create("YOUR_API_KEY") }

Add import statements

In the Android tool window, open app > kotlin+java > com.example.app > MainScreen.kt. Replace the import statements with the imports needed for this tutorial.

MainScreen.kt
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@file:OptIn(ExperimentalMaterial3Api::class)

package com.example.app.screens

import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.ExperimentalMaterial3Api
import androidx.compose.material3.Scaffold
import androidx.compose.material3.Text
import androidx.compose.material3.TopAppBar
import androidx.compose.runtime.Composable
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.res.stringResource
import com.arcgismaps.Color
import com.arcgismaps.data.ServiceFeatureTable
import com.arcgismaps.mapping.ArcGISMap
import com.arcgismaps.mapping.BasemapStyle
import com.arcgismaps.mapping.Viewpoint
import com.arcgismaps.mapping.labeling.ArcadeLabelExpression
import com.arcgismaps.mapping.labeling.LabelDefinition
import com.arcgismaps.mapping.layers.FeatureLayer
import com.arcgismaps.mapping.symbology.ClassBreak
import com.arcgismaps.mapping.symbology.ClassBreaksRenderer
import com.arcgismaps.mapping.symbology.FontStyle
import com.arcgismaps.mapping.symbology.FontWeight
import com.arcgismaps.mapping.symbology.PictureMarkerSymbol
import com.arcgismaps.mapping.symbology.SimpleFillSymbol
import com.arcgismaps.mapping.symbology.SimpleFillSymbolStyle
import com.arcgismaps.mapping.symbology.SimpleLineSymbol
import com.arcgismaps.mapping.symbology.SimpleLineSymbolStyle
import com.arcgismaps.mapping.symbology.SimpleRenderer
import com.arcgismaps.mapping.symbology.TextSymbol
import com.arcgismaps.mapping.symbology.UniqueValue
import com.arcgismaps.mapping.symbology.UniqueValueRenderer
import com.arcgismaps.toolkit.geoviewcompose.MapView
import com.example.app.R

Create a function to add a feature layer

You can add a feature layer from a feature service hosted in ArcGIS. Each feature layer contains features with a single geometry type (point, line, or polygon), and a set of attributes. Once added to the map, feature layers can be symbolized, styled, and labeled in a variety of ways.

Define variables that store feature service URLs used by the app's layers, and then create a helper function to add a layer to the map's list of operational layers. You will use this code throughout the tutorial as you add and symbolize various layers.

In createMap() add four read-only String variables: three for accessing feature layers, and a fourth for accessing a static image for use in a picture marker symbol. You will use these resources in future steps.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

    }
}
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In the apply block for ArcGISMap, insert code that adds FeatureLayers to the map's operationalLayers. For now, the listOf() function has no parameters. In this tutorial, you will be adding each new feature layer to the list of parameters.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

        operationalLayers.addAll(

            listOf(

            )

        )

    }
}
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Add a top-level helper function named createFeatureLayer() that takes a feature service URI as an argument and returns a FeatureLayer created from the URI.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.fun createFeatureLayer(featureServiceUri: String): FeatureLayer {
    // Create a service feature table from a Uri
    val serviceFeatureTable = ServiceFeatureTable(featureServiceUri)
    // Return a feature layer created from the service feature table
    return FeatureLayer.createWithFeatureTable(serviceFeatureTable)
}
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Add a layer with a unique value renderer

Create a method to apply a different symbol for each type of park area to the Parks and Open Spaces feature layer.

Add a top-level function named createOpenSpaceLayer().

UniqueValue assigns a symbol to a value or values. A unique value renderer uses a collection of unique values to assign the appropriate symbol for each feature it renderers.

For this example, the renderer uses a feature's TYPE attribute value to apply the correct symbol.

MainScreen.kt
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    // Create fill symbol objects to represent the parks and open spaces layer
    val magentaFillSymbol = SimpleFillSymbol(SimpleFillSymbolStyle.Solid, Color.fromRgba(255, 0, 255), null)
    val greenFillSymbol = SimpleFillSymbol(SimpleFillSymbolStyle.Solid, Color.green, null)
    val blueFillSymbol = SimpleFillSymbol(SimpleFillSymbolStyle.Solid, Color.fromRgba(0, 0, 255), null)
    val redFillSymbol = SimpleFillSymbol(SimpleFillSymbolStyle.Solid, Color.red, null)

    // Create a unique value for natural areas, regional open spaces, local parks, and regional recreation parks
    val naturalAreas = UniqueValue(
        description = "Natural Areas",
        label = "Natural Areas",
        symbol = magentaFillSymbol,
        values = listOf("Natural Areas")
    )
    val regionalOpenSpace = UniqueValue(
        description = "Regional Open Space",
        label = "Regional Open Space",
        symbol = greenFillSymbol,
        values = listOf("Regional Open Space")
    )
    val localPark = UniqueValue(
        description = "Local Park",
        label = "Local Park",
        symbol = blueFillSymbol,
        values = listOf("Local Park")
    )
    val regionalRecreationPark = UniqueValue(
        description = "Regional Recreation Park",
        label = "Regional Recreation Park",
        symbol = redFillSymbol,
        values = listOf("Regional Recreation Park")
    )
    // Create a unique value list with the fill symbols
    val uniqueValuesList = listOf(
        naturalAreas,
        regionalOpenSpace,
        localPark,
        regionalRecreationPark
    )

    // Create and assign a unique value renderer to the feature layer
    val openSpacesUniqueValueRenderer =
        UniqueValueRenderer(
            fieldNames = listOf("TYPE"),
            uniqueValues = uniqueValuesList,
            defaultLabel = "Open Spaces",
            defaultSymbol = null
        )

    // Create a parks and open spaces feature layer
    val featureLayer = createFeatureLayer(featureServiceUri).apply {
        // Style the feature layer using the unique value renderer
        renderer = openSpacesUniqueValueRenderer
        // Set the layer opacity to semi-transparent
        opacity = 0.2f
    }

    return featureLayer
}
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In createMap(), add the Parks and Open Space feature layer to the map's operational layers by calling createOpenSpaceLayer().

MainScreen.kt
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Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

        operationalLayers.addAll(

            listOf(

                createOpenSpaceLayer(parksAndOpenSpaces),

            )

        )

    }
}
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Click Run > Run > app to run the app.

When the app opens, Parks and Open Spaces feature layer is added to the map. The map displays the different types of parks and open spaces with four unique symbols.

Add a layer with a class breaks renderer

Create a method to apply a different symbol for each of the five ranges of elevation gain to the Trails feature layer.

Add a top-level function named createTrailsLayer().

A ClassBreak assigns a symbol to a range of values.

For this example, the renderer uses each feature's ELEV_GAIN attribute value to classify it into a defined range (class break) and apply the corresponding symbol.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun createTrailsLayer(featureServiceUri: String): FeatureLayer {
    // Create simple symbol objects to represent the trails layer
    val firstClassSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.fromRgba(255, 0, 255), 3.0f)
    val secondClassSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.fromRgba(255, 0, 255), 4.0f)
    val thirdClassSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.fromRgba(255, 0, 255), 5.0f)
    val fourthClassSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.fromRgba(255, 0, 255), 6.0f)
    val fifthClassSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Solid, Color.fromRgba(255, 0, 255), 7.0f)

    // Create 5 class breaks
    val firstClassBreak = ClassBreak(
        description = "Under 500",
        label = "0 - 500",
        minValue = 0.0,
        maxValue = 500.0,
        symbol = firstClassSymbol
    )
    val secondClassBreak = ClassBreak(
        description = "501 to 1000",
        label = "501 - 1000",
        minValue = 501.0,
        maxValue = 1000.0,
        symbol = secondClassSymbol
    )
    val thirdClassBreak = ClassBreak(
        description = "1001 to 1500",
        label = "1001 - 1500",
        minValue = 1001.0,
        maxValue = 1500.0,
        symbol = thirdClassSymbol
    )
    val fourthClassBreak = ClassBreak(
        description = "1501 to 2000",
        label = "1501 - 2000",
        minValue = 1501.0,
        maxValue = 2000.0,
        symbol = fourthClassSymbol
    )
    val fifthClassBreak = ClassBreak(
        description = "2001 to 2300",
        label = "2001 - 2300",
        minValue = 2001.0,
        maxValue = 2300.0,
        symbol = fifthClassSymbol
    )
    val elevationBreaks = listOf(
        firstClassBreak,
        secondClassBreak,
        thirdClassBreak,
        fourthClassBreak,
        fifthClassBreak
    )

    // Create and assign a class breaks renderer to the feature layer
    val elevationClassBreaksRenderer = ClassBreaksRenderer("ELEV_GAIN", elevationBreaks)

    // Create a trails feature layer
    val featureLayer = createFeatureLayer(featureServiceUri).apply {
        // Style the feature layer using the class breaks renderer
        renderer = elevationClassBreaksRenderer
        // Set the layer opacity to semi-transparent
        opacity = 0.75f
    }

    return featureLayer
}
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Update createMap() to call the new createTrailsLayer() function.

MainScreen.kt
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Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

        operationalLayers.addAll(

            listOf(

                createOpenSpaceLayer(parksAndOpenSpaces),

                createTrailsLayer(trails),

            )

        )

    }
}
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Click Run > Run > app to run the app.

When the app opens, the Trails feature layer is added to the map. The map displays trails with different symbols depending on trail elevation.

Add layers with definition expressions

You can use a definition expression to define a subset of features to display. Features that do not meet the expression criteria are not displayed by the layer. In the following steps, you will create two methods that use a definition expression to apply a symbol to a subset of features in the Trails feature layer.

FeatureLayer.definitionExpression uses a SQL expression to limit the features available for query and display. Your code will create two layers that each display a different subset of trails based on the value for the USE_BIKE field. Trails that allow bikes will be symbolized with a blue symbol ("USE_BIKE = 'Yes'") and those that don't will be yellowred ("USE_BIKE = 'No'"). Another way to symbolize these features would be to create a UniqueValueRenderer that applies a different symbol for these values.

Add a top-level function named createBikeOnlyTrailsLayer() that uses a definitionExpression to filter for trails that permit bikes.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun createBikeOnlyTrailsLayer(featureServiceUri: String): FeatureLayer {
    // Create blue dot style simple line symbol to represent the bike trails
    val bikeTrailSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Dot, Color.fromRgba(0, 0, 255), 2.0f)
    // Create a simple renderer for the feature layer
    val bikeTrailRenderer = SimpleRenderer(bikeTrailSymbol)

    // Create a bike trails feature layer
    val featureLayer = createFeatureLayer(featureServiceUri).apply {
        // Style the feature layer using the simple renderer
        renderer = bikeTrailRenderer
        // Write a definition expression to filter for trails that permit the use of bikes
        definitionExpression = "USE_BIKE = 'Yes'"
    }

    return featureLayer
}
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Add another top-level function named createNoBikeTrailsLayer() with a definition expression to filter for trails that don't allow bikes.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun createNoBikeTrailsLayer(featureServiceUri: String): FeatureLayer {
    // Create a yellow dot style simple line symbol to represent no bike trails
    val noBikeTrailSymbol = SimpleLineSymbol(SimpleLineSymbolStyle.Dot, Color.fromRgba(255, 255, 0), 2.0f)
    // Create a simple renderer for the feature layer
    val noBikeTrailRenderer = SimpleRenderer(noBikeTrailSymbol)

    // Create a no-bike trails feature layer
    val featureLayer = createFeatureLayer(featureServiceUri).apply {
        // Style the feature layer using the simple renderer
        renderer = noBikeTrailRenderer
        // Write a definition expression to filter for trails that don't permit the use of bikes
        definitionExpression = "USE_BIKE = 'No'"
    }

    return featureLayer
}
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Update createMap() to call the new createBikeOnlyTrailsLayer() and createNoBikeTrailsLayer() functions.

MainScreen.kt
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Add line.Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

        operationalLayers.addAll(

            listOf(

                createOpenSpaceLayer(parksAndOpenSpaces),

                createTrailsLayer(trails),

                createBikeOnlyTrailsLayer(trails),

                createNoBikeTrailsLayer(trails),

            )

        )

    }
}
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Click Run > Run > app to run the app.

When the app opens, two Trails feature layers are added to the map. One shows where bikes are permitted and the other where they are prohibited.

Symbolize a layer with a picture symbol and label features with an attribute

Create a method to style trailheads with hiker images and labels for the Trailheads feature layer.

Feature layers, graphics overlays, and map image layer sublayers in your app can be labeled using a combination of attribute values, text strings, and values calculated with an expression. You can determine how labels are positioned and prioritized, and how conflicts between overlapping labels are automatically and dynamically resolved.

For feature layers, graphics overlays, and map image sublayers, labeling is implemented using a collection of LabelDefinition objects to define what labels look like (font, size, color, angle, and so on), the scale at which they display, the text they contain, how they handle overlaps, and so on.

If you want to label everything in your layer or overlay to look identical, you can define a single label definition. If you want to use different label formatting for different attribute values, you can add as many label definitions as you need to define distinct sets of geoelements for labeling.

Add a top-level function named createTrailheadsLayer().

Use a PictureMarkerSymbol to draw a trailhead hiker image. Use the LabelDefinition to label each trailhead by its name.

MainScreen.kt
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    // Create a new picture marker symbol that uses the trailhead image
    val pictureMarkerSymbol = PictureMarkerSymbol(trailheadImage).apply {
        height = 18.0f
        width = 18.0f
    }
    // Create a new simple renderer based on the picture marker symbol
    val simpleRenderer = SimpleRenderer(pictureMarkerSymbol)
    // Create the label definition
    val trailHeadsDefinition = makeLabelDefinition(labelAttribute = "TRL_NAME")

    // Create a trail heads feature layer
    val featureLayer: FeatureLayer = createFeatureLayer(featureServiceUri).apply {
        // Style the feature layer using the simple renderer
        renderer = simpleRenderer
        // Set labeling on the layer to be enabled
        labelsEnabled = true
        // Add the label definition to the layer's label definition collection
        labelDefinitions.add(trailHeadsDefinition)
    }

    return featureLayer
}
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Create a top-level function named makeLabelDefinition() that defines a label definition based on the passed in feature layer attribute. This helper function will also define the label placement and text symbol.

MainScreen.kt
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Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.Add line.fun makeLabelDefinition(labelAttribute: String): LabelDefinition {
    // Create a text symbol for the label definition
    val labelTextSymbol = TextSymbol().apply {
        color = Color.white
        size = 12.0f
        haloColor = Color.red
        haloWidth = 1.0f
        fontFamily = "Arial"
        fontStyle = FontStyle.Italic
        fontWeight = FontWeight.Normal
    }

    // Create an Arcade label expression based on the field name
    val labelExpression = ArcadeLabelExpression("\$feature.$labelAttribute")

    // Create and return the label definition
    return LabelDefinition(labelExpression, labelTextSymbol)
}

Update createMap() to call the new createTrailheadsLayer() function.

MainScreen.kt
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Add line.fun createMap(): ArcGISMap {

    val parksAndOpenSpaces =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Parks_and_Open_Space/FeatureServer/0"
    val trails =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trails/FeatureServer/0"
    val trailheads =
        "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/Trailheads/FeatureServer/0"
    val trailheadImage =
        "https://static.arcgis.com/images/Symbols/NPS/npsPictograph_0231b.png"

    return ArcGISMap(BasemapStyle.ArcGISTopographic).apply {
        initialViewpoint = Viewpoint(
            latitude = 34.0270,
            longitude = -118.8050,
            scale = 72000.0
        )

        operationalLayers.addAll(

            listOf(

                createOpenSpaceLayer(parksAndOpenSpaces),

                createTrailsLayer(trails),

                createBikeOnlyTrailsLayer(trails),

                createNoBikeTrailsLayer(trails),

                createTrailheadsLayer(trailheads, trailheadImage)

            )

        )

    }
}
Expand

Click Run > Run > app to run the app.

When the app opens, all the layers you've created and symbolized are displayed on the map.

Parks and open spaces are displayed with four unique symbols
Trails use different symbols (line widths) depending on trail elevation
Trails are blue where bikes are permitted and red where they are prohibited
Trailheads are displayed with a hiker icon and labels display each trail's name

What's next?

Learn how to use additional API features, ArcGIS location services, and ArcGIS tools in these tutorials:

ArcGIS Maps SDK for Kotlin

Style a feature layer

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