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Render features in a layer using a distinct symbol for each unique attribute value.

Image of unique value renderer

Use case

A unique value renderer allows you to symbolize features in a layer based on one or more matching attributes. This is typically done by using unique colors, fill styles, or images to represent features with equal values in a string field. A unique value renderer could be used to show different types of trees on a vegetation map by using a symbols corresponding to matching name attributes.

How to use the sample

The map with the symbolized feature layer will be shown automatically when the sample loads.

How it works

  1. Define a SimpleFillSymbol for each type of feature.
  2. Apply the SimpleFillSymbol to polygon features, which is the type of feature contained by this ServiceFeatureTable.
  3. Create separate UniqueValue objects which define the values in the renderer field and the symbol used to render matching features.
  4. Create a default symbol to render all features that do not match any of the UniqueValue objects defined.

Relevant API

  • FeatureLayer
  • ServiceFeatureTable
  • SimpleFillSymbol
  • SimpleLineSymbol
  • UniqueValue
  • UniqueValueRenderer

Additional information

Using the UniqueValueRenderer, separate symbols can be used to display features that have a specific value for a given field. In this case, the field is subregions of the USA. While multiple fields can be used, this sample only uses one.

About the data

The map shows U.S. states symbolized by subregion. Symbols are defined for Pacific, Mountain, and West South Central states. All other features are symbolized with the default symbol.

Tags

draw, renderer, symbol, symbology, values

Sample Code

module-info.java module-info.java UniqueValueRendererSample.java
/*
* Copyright 2022 Esri.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
module com.esri.samples.unique_value_renderer {
// require ArcGIS Maps SDK for Java module
requires com.esri.arcgisruntime;
// handle SLF4J http://www.slf4j.org/codes.html#StaticLoggerBinder
requires org.slf4j.nop;
// require JavaFX modules that the application uses
requires javafx.graphics;
exports com.esri.samples.unique_value_renderer;
}