import javafx.application.Application;
import javafx.stage.Stage;
import javafx.scene.*;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.event.*;
import javafx.collections.*;
import java.util.*;
public class ExListView extends Application
{
  private ListView                  lvRect;
  private ArrayList<Rectangle>      ayRect;
  private ObservableList<Rectangle> obRect;
  private TextField                 tfLength, tfWidth;
  public void init()
  {
    ayRect = new ArrayList();
    ayRect.add(new Rectangle(10, 1));
    ayRect.add(new Rectangle(20, 1));
    ayRect.add(new Rectangle(30, 1));
    obRect = FXCollections.observableList(ayRect);
  }
  public void start(Stage topView)
  {
    FlowPane fPane = new FlowPane();
    topView.setScene(new Scene(fPane));
    // Adding ListView
    lvRect = new ListView(obRect);
    lvRect.setTooltip(new Tooltip("Rectangle"));
    fPane.getChildren().add(lvRect);
    // ListView selection
    lvRect.setOnMouseClicked(evt -> showSelected(evt));

    // TextField and Button for adding Rectangle instance
    tfLength = new TextField();
    tfWidth  = new TextField();
    Button addRect = new Button("Add");
    addRect.setOnAction(evt -> doAddRect(evt));

    VBox inputBox = new VBox(10);
    inputBox.getChildren().addAll(tfLength, tfWidth, addRect);
    fPane.getChildren().add(inputBox);

    topView.show();
  }
  private void doAddRect(ActionEvent evt)
  {
    double length = Double.parseDouble(tfLength.getText());
    double width  = Double.parseDouble(tfWidth.getText());
    Rectange rect = new Rectangle(length, width);

    obRect.add(rect);


    // Checking
    System.out.println("ArrayList");
    for (Rectangle r : ayRect)
      System.out.println(r);

    System.out.println("ObservableList");
    for (Rectangle r : obRect)
      System.out.println(r);

  }
  private void showSelected(Event evt)
  {
    ObservableList<Rectangle> itemsSelected =
      lvRect.getSelectionModel().getSelectedItems();
    for (Rectangle r : itemsSelected)
      System.out.println(r);
  }
  public static void main(String[] argv)
  {
    launch(argv);
  }
}