select Features from a FeatureLayer using esri - Java Geographic Information System

Java examples for Geographic Information System:Esri

Description

select Features from a FeatureLayer using esri

Demo Code

  /*/* w w w . j a v  a2  s  .  c  om*/
   * Copyright 2015 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.
   */

  package com.esri.sampleviewer.samples.featurelayers;

  import java.util.concurrent.atomic.AtomicInteger;

  import javafx.application.Application;
  import javafx.application.Platform;
  import javafx.geometry.Insets;
  import javafx.geometry.Point2D;
  import javafx.geometry.Pos;
  import javafx.scene.Scene;
  import javafx.scene.control.Label;
  import javafx.scene.control.TextArea;
  import javafx.scene.input.MouseButton;
  import javafx.scene.input.MouseEvent;
  import javafx.scene.layout.StackPane;
  import javafx.scene.layout.VBox;
  import javafx.stage.Stage;

  import com.esri.arcgisruntime.concurrent.ListenableFuture;
  import com.esri.arcgisruntime.datasource.FeatureQueryResult;
  import com.esri.arcgisruntime.datasource.QueryParameters;
  import com.esri.arcgisruntime.datasource.QueryParameters.SpatialRelationship;
  import com.esri.arcgisruntime.datasource.arcgis.ServiceFeatureTable;
  import com.esri.arcgisruntime.geometry.Envelope;
  import com.esri.arcgisruntime.geometry.GeometryEngine;
  import com.esri.arcgisruntime.geometry.Point;
  import com.esri.arcgisruntime.geometry.Polygon;
  import com.esri.arcgisruntime.geometry.SpatialReferences;
  import com.esri.arcgisruntime.layers.FeatureLayer;
  import com.esri.arcgisruntime.layers.FeatureLayer.SelectionMode;
  import com.esri.arcgisruntime.mapping.Basemap;
  import com.esri.arcgisruntime.mapping.Map;
  import com.esri.arcgisruntime.mapping.view.MapView;
  import com.esri.arcgisruntime.mapping.view.Viewpoint;
  import com.esri.arcgisruntime.symbology.RgbColor;

  /**
   * This sample demonstrates how to select Features from a FeatureLayer.
   * <p>
   * A {@link FeatureLayer} allows us to work with Features from a table, like
   * displaying Features to Map.
   * <h4>How it Works</h4>
   * 
   * A {@link ServiceFeatureTable} is created from a URL and then a FeatureLayer
   * is created by supplying that table. The {@link FeatureLayer#selectFeatures}
   * method will select Features filtered by the {@link QueryParameters} that was
   * passed to it.
   * 
   * <p>
   * A ListenableFuture needs to be a class level field because it could get
   * garbage collected right after being set.
   */
  public class FeatureLayerSelection extends Application {

      private MapView mapView;
      private ServiceFeatureTable featureTable;
      private FeatureLayer featureLayer;

      private ListenableFuture<FeatureQueryResult> queryResult;

      private static final String SERVICE_FEATURE_URL = "http://sampleserver6.arcgisonline.com/arcgis/rest/services/DamageAssessment/FeatureServer/0";
      private static final String SAMPLES_THEME_PATH = "../resources/SamplesTheme.css";

      @Override
public void start(Stage stage) throws Exception {

  // create stack pane and application scene
  StackPane stackPane = new StackPane();
  Scene scene = new Scene(stackPane);
  scene.getStylesheets().add(getClass().getResource(SAMPLES_THEME_PATH)
      .toExternalForm());

  // set title, size, and add scene to stage
  stage.setTitle("Feature Layer Selection Sample");
  stage.setWidth(800);
  stage.setHeight(700);
  stage.setScene(scene);
  stage.show();

  // create a control panel
  VBox vBoxControl = new VBox(6);
  vBoxControl.setMaxSize(250, 190);
  vBoxControl.getStyleClass().add("panel-region");

  // create sample label and description
  Label descriptionLabel = new Label("Sample Description");
  descriptionLabel.getStyleClass().add("panel-label");
  TextArea description = new TextArea(
      "This sample demonstrates how to select Features from a Feature Layer. "
          + "Click a Feature to select it and any Features within a certain "
          + "distance.");
  description.setWrapText(true);
  description.autosize();
  description.setEditable(false);

  // add sample label and description to the control panel
  vBoxControl.getChildren().addAll(descriptionLabel, description);
  try {

    // create a map with the streets basemap
    final Map map = new Map(Basemap.createStreets());

    // set an initial viewpoint
    Point leftPoint = new Point(-1131596.019761, 3893114.069099,
        SpatialReferences.getWebMercator());
    Point rightPoint = new Point(3926705.982140, 7977912.461790,
        SpatialReferences.getWebMercator());

    map.setInitialViewpoint(new Viewpoint(new Envelope(leftPoint,
        rightPoint)));

    // create the service feature table
    featureTable = new ServiceFeatureTable(SERVICE_FEATURE_URL);

    // create the feature layer using the service feature table
    featureLayer = new FeatureLayer(featureTable);
    featureLayer.setSelectionColor(new RgbColor(0, 255, 255, 255)); // cyan, fully opaque
    featureLayer.setSelectionWidth(3);

    // add the layer to the map
    map.getOperationalLayers().add(featureLayer);

    // create a view for this map and set map to it
    mapView = new MapView();
    mapView.setMap(map);

    mapView.addEventHandler(MouseEvent.MOUSE_CLICKED, e -> {
      if (e.getButton() == MouseButton.PRIMARY) {
        // create point from where user clicked
        Point2D point = new Point2D(e.getX(), e.getY());

        // create map point from point
        Point mapPoint = mapView.screenToLocation(point);

        // select feature that user clicked
        selectFeatures(mapPoint);
      }
    });

    // add the map view and control box to stack pane
    stackPane.getChildren().addAll(mapView, vBoxControl);
    StackPane.setAlignment(vBoxControl, Pos.TOP_LEFT);
    StackPane.setMargin(vBoxControl, new Insets(10, 0, 0, 10));
  } catch (Exception e) {
    // on any error, display exception
    e.printStackTrace();
  }
}

      /**
       * Selects features around map point.
       * 
       * @param mapPoint x,y coordinate pair
       */
      private void selectFeatures(Point mapPoint) {

  // create a buffer for the mapPoint
  double distance = mapView.getUnitsPerPixel() * 10;
  Polygon pointBuffer = GeometryEngine.buffer(mapPoint, distance);

  // create a query from pointBuffer
  QueryParameters queryParams = new QueryParameters();
  queryParams.setGeometry(pointBuffer);
  queryParams.setSpatialRelationship(SpatialRelationship.WITHIN);
  queryParams.getOutFields().add("*");

  // select the features based on the query
  queryResult = featureLayer.selectFeatures(queryParams, SelectionMode.NEW);

  try {
    // get selected features from the result
    FeatureQueryResult selectedFeatures = queryResult.get();

    AtomicInteger numberOfFeatures = new AtomicInteger(0);
    selectedFeatures.forEach(feature -> numberOfFeatures.incrementAndGet());

  } catch (Exception e) {
    // on any error, display the stack trace
    e.printStackTrace();
  }
}

      /**
       * Stops and releases all resources used in application.
       * 
       * @throws Exception if security manager doesn't allow JVM to exit with
       *           current status
       */
      @Override
      public void stop() throws Exception {

          // release resources when the application closes
          if (mapView != null) {
              mapView.dispose();
          }
          Platform.exit();
          System.exit(0);
      }

      /**
       * Opens and runs application.
       * 
       * @param args arguments passed to this application
       */
      public static void main(String[] args) {

          Application.launch(args);
      }
  }

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