Implement event handler to get data of individual node of PieChart

We can implement EventHandler of MouseEvent for individual node of a PieChart, to read data of the node by calling getName() and getPieValue().

Example:

package javafx_charts;

import java.awt.event.MouseEvent;
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.event.EventType;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.chart.PieChart;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.layout.StackPane;
import javafx.scene.shape.LineTo;
import javafx.scene.shape.MoveTo;
import javafx.stage.Stage;

/**
*
* @web http://java-buddy.blogspot.com/
*/
public class JavaFX_Charts extends Application {

  Label label;

  /**
   * @param args the command line arguments
   */
  public static void main(String[] args) {
      launch(args);
  }

  @Override
  public void start(Stage primaryStage) {
      primaryStage.setTitle("java-buddy.blogspot.com");
      Group root = new Group();
    
      ObservableList<PieChart.Data> pieChartData =
              FXCollections.observableArrayList(
                  new PieChart.Data("January", 100),
                  new PieChart.Data("February", 200),
                  new PieChart.Data("March", 50),
                  new PieChart.Data("April", 75),
                  new PieChart.Data("May", 110),
                  new PieChart.Data("June", 300),
                  new PieChart.Data("July", 111),
                  new PieChart.Data("August", 30),
                  new PieChart.Data("September", 75),
                  new PieChart.Data("October", 55),
                  new PieChart.Data("November", 225),
                  new PieChart.Data("December", 99));
    
      final PieChart pieChart = new PieChart(pieChartData);
      pieChart.setTitle("PieChart");
    
      label = new Label("");
    
      //add event handler
      for(final PieChart.Data data : pieChart.getData()){
        
          data.getNode().addEventHandler(
                  javafx.scene.input.MouseEvent.MOUSE_PRESSED,
                  new EventHandler<javafx.scene.input.MouseEvent>() {
                    
                      @Override
                      public void handle(javafx.scene.input.MouseEvent mouseEvent) {

                          String name = data.getName();
                          double value = data.getPieValue();
                          label.setText(name + " : " + String.valueOf(value));
                      }
                  });
        
          data.getNode().addEventHandler(
                  javafx.scene.input.MouseEvent.MOUSE_RELEASED,
                  new EventHandler<javafx.scene.input.MouseEvent>() {
                    
                      @Override
                      public void handle(javafx.scene.input.MouseEvent mouseEvent) {
                          label.setText("");
                      }
                  });
      }
    
      root.getChildren().add(pieChart);
      root.getChildren().add(label);

      primaryStage.setScene(new Scene(root, 500, 400));
      primaryStage.show();
  }

}

Related article:
- Create and update PieChart from TableView