CanvasTest.java

//package canvastest;

import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.effect.DropShadow;
import javafx.scene.paint.Color;
import javafx.scene.paint.CycleMethod;
import javafx.scene.paint.LinearGradient;
import javafx.scene.paint.RadialGradient;
import javafx.scene.paint.Stop;
import javafx.stage.Stage;

public class CanvasTest extends Application {

    private Canvas canvas = new Canvas(200, 200);
    private GraphicsContext gc = canvas.getGraphicsContext2D();
    private Group root = new Group();

    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("Canvas Test");
        moveCanvas(0,0);
        drawDShape();
        drawRadialGradient(Color.RED, Color.YELLOW);
        drawLinearGradient(Color.BLUE, Color.GREEN);
        drawDropShadow(Color.GRAY, Color.BLUE, Color.GREEN, Color.RED);
        root.getChildren().add(canvas);
        primaryStage.setScene(new Scene(root, 400, 400));
        primaryStage.show();
    }

    /**
     * Moves the canvas to a new location within the Scene. This is accomplished
     * by performing a translation transformation on the Canvas object, passing 
     * in the desired x and y coordinates. Passing in values of 0,0 will position
     * the Canvas in the upper left corner of the Scene.
     * @param x The new x coordinate
     * @param y The new y coordinate
     */
    private void moveCanvas(int x, int y) {
        canvas.setTranslateX(x);
        canvas.setTranslateY(y);
    }

    /**
     * Draws an area in the shape of a capital letter "D."
     * The user can try substituting numbers 
     * of their own in the bezierCurveTo parameters to 
     * warp the shape away from the letter "D."
     */
    private void drawDShape() {
        gc.beginPath();
        gc.moveTo(50, 50);
        gc.bezierCurveTo(150, 20, 150, 150, 75, 150);
        gc.closePath();
    }

    /**
     * Draws a radial gradient on the Canvas object, which appears as a series of
     * circles radiating outward. This demo uses RED and YELLOW by default. 
     * 
     * @param firstColor The color used in the first Stop of the gradient.
     * @param lastColor  The color used in the last Stop of the gradient.
     */
    private void drawRadialGradient(Color firstColor, Color lastColor) {
        gc.setFill(new RadialGradient(0, 0, 0.5, 0.5, 0.1, true,
                CycleMethod.REFLECT,
                new Stop(0.0, firstColor),
                new Stop(1.0, lastColor)));
        gc.fill();
    }

    /**
     * Draws a linear gradient on the Canvas object, which colors the letter "D"
     * from top to bottom. The default colors used in this demo are BLUE and GREEN.
     * 
     * @param firstColor
     * @param secondColor 
     */
    private void drawLinearGradient(Color firstColor, Color secondColor) {
        LinearGradient lg = new LinearGradient(0, 0, 1, 1, true,
                CycleMethod.REFLECT,
                new Stop(0.0, firstColor),
                new Stop(1.0, secondColor));
        gc.setStroke(lg);
        gc.setLineWidth(20);
        gc.stroke();
    }

    /**
     * Draws a four separate drop shadows around the letter "D." The default 
     * colors used in the demo are GREY, BLUE, GREEN, and RED. 
     * 
     * @param firstColor
     * @param secondColor
     * @param thirdColor
     * @param fourthColor 
     */
    private void drawDropShadow(Color firstColor, Color secondColor,
            Color thirdColor, Color fourthColor) {
        gc.applyEffect(new DropShadow(20, 20, 0, firstColor));
        gc.applyEffect(new DropShadow(20, 0, 20, secondColor));
        gc.applyEffect(new DropShadow(20, -20, 0, thirdColor));
        gc.applyEffect(new DropShadow(20, 0, -20, fourthColor));
    }
}