JAVAFX BASICS - Introduction to Java Programming: Comprehensive Version - page 567

10 public void start(Stage primaryStage) {

11 // Create a pane

12 Pane pane = new Pane();

create a pane

13
14 for ( int i = 0 ; i < 16 ; i++) {
15 // Create an ellipse and add it to pane
16 Ellipse e1 = new Ellipse( 150 , 100 , 100 , 50 );
17 e1.setStroke(Color.color(Math.random(), Math.random(),
18 Math.random()));
19 e1.setFill(Color.WHITE);
20

create an ellipse
set random color for stroke

set fill color
rotate ellipse
add ellipse to pane

e1.setRotate(i * 180 / 16 );

21 pane.getChildren().add(e1);

22 }
23
24 // Create a scene and place it in the stage
25 Scene scene = new Scene(pane, 300 , 200 );
26 primaryStage.setTitle( "ShowEllipse" ); // Set the stage title
27 primaryStage.setScene(scene); // Place the scene in the stage
28 primaryStage.show(); // Display the stage
29 }
30 }

The program repeatedly creates an ellipse (line 16), sets a random stroke color (lines
17-18), sets its fill color to white (line 19), rotates it (line 20), and adds the rectangle to the
pane (line 21).

14.11.5 Arc
An arc is conceived as part of an ellipse, defined by the parameters centerX , centerY ,
radiusX , radiusY , startAngle , length , and an arc type ( ArcType.OPEN , ArcType
.CHORD , or ArcType.ROUND ). The parameter startAngle is the starting angle; and length
is the spanning angle (i.e., the angle covered by the arc). Angles are measured in degrees and
follow the usual mathematical conventions (i.e., 0 degrees is in the easterly direction, and
positive angles indicate counterclockwise rotation from the easterly direction), as shown in
Figure 14.36a.
The Arc class defines an arc. The UML diagram for the Arc class is shown in Figure 14.35.
Listing 14.18 gives an example that demonstrates ellipses, as shown in Figure 14.36b.

The getter and setter methods for property values
and a getter for property itself are provided in the class,
but omitted in the UML diagram for brevity.

javafx.scene.shape.Arc

-centerX: DoubleProperty
-centerY: DoubleProperty
-radiusX: DoubleProperty
-radiusY: DoubleProperty
-startAngle: DoubleProperty
-length: DoubleProperty
-type: ObjectProperty<ArcType>

The x-coordinate of the center of the ellipse (default 0 ).
The y-coordinate of the center of the ellipse (default 0 ).
The horizontal radius of the ellipse (default: 0 ).
The vertical radius of the ellipse (default: 0 ).
The start angle of the arc in degrees.
The angular extent of the arc in degrees.
The closure type of the arc ( ArcType.OPEN, ArcType.CHORD,
ArcType.ROUND ).

+Arc()
+Arc(x: double, y: double,
radiusX: double, radiusY:
double, startAngle: double,
length: double)

Creates an empty Arc .
Creates an Arc with the specified arguments.

F IGURE 14.35

The Arc class defines an arc.