javafx实现图形编辑器

下面是一个简单的示例，使用JavaFX实现了一个基本的图形编辑器，可以绘制矩形和圆形。

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.layout.BorderPane;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

public class GraphicsEditor extends Application {

    private Canvas canvas;
    private GraphicsContext gc;
    private ShapeType currentShapeType;
    private double startX, startY, endX, endY;

    public enum ShapeType {
        RECTANGLE, CIRCLE
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        canvas = new Canvas(800, 600);
        gc = canvas.getGraphicsContext2D();

        canvas.setOnMousePressed(e -> {
            startX = e.getX();
            startY = e.getY();
        });

        canvas.setOnMouseReleased(e -> {
            endX = e.getX();
            endY =