javafx.scene.package-info Maven / Gradle / Ivy
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/**
* Provides the core set of base
* classes for the JavaFX Scene Graph API. A scene graph is a tree-like
* data structure, where each item in the tree has zero or one parent and
* zero or more children.
*
* The two primary classes in this package are:
*
*
*
* - {@link javafx.scene.Scene Scene} – Defines the scene to be rendered. It
* contains a {@code fill} variable that specifies the background of
* the scene, {@code width} and {@code height} variables that
* specify the size of the scene, and a {@code content} sequence
* that contains a list of "root" {@code Nodes} to be rendered onto
* the scene. This sequence of {@code Nodes} is the scene graph for
* this {@code Scene}.
* A {@code Scene} is rendered onto a {@link javafx.stage.Stage}, which is the
* top-level container for JavaFX content.
*
* - {@link javafx.scene.Node Node} – Abstract base class for all nodes in the
* scene graph. Each node is either a "leaf" node with no child nodes or
* a "branch" node with zero or more child nodes. Each node in the tree
* has zero or one parent. Only a single node within each tree in the
* scene graph will have no parent, which is often referred to as the
* "root" node.
* There may be several trees in the scene graph. Some trees may be part of
* a {@link javafx.scene.Scene Scene}, in which case they are eligible to be displayed.
* Other trees might not be part of any {@link javafx.scene.Scene Scene}.
*
*
*
* Branch nodes are of type {@link javafx.scene.Parent Parent} or
* subclasses thereof.
*
* Leaf nodes are classes such as
* {@link javafx.scene.shape.Rectangle}, {@link javafx.scene.text.Text},
* {@link javafx.scene.image.ImageView}, {@link javafx.scene.media.MediaView},
* or other such leaf classes which cannot have children.
*
*
A node may occur at most once anywhere in the scene
* graph. Specifically, a node must appear no more than once in the children
* list of a {@link javafx.scene.Parent Parent} or as the clip of a
* {@link javafx.scene.Node Node}.
* See the {@link javafx.scene.Node Node} class for more details on these restrictions.
*
* Example
*
* An example JavaFX scene graph is as follows:
*
*
* package example;
*
* import javafx.application.Application;
* import javafx.stage.Stage;
* import javafx.scene.Scene;
* import javafx.scene.Group;
* import javafx.scene.paint.Color;
* import javafx.scene.shape.Circle;
* import javafx.scene.text.Text;
* import javafx.scene.text.Font;
*
* public class Example extends Application {
*
* @Override public void start(Stage stage) {
*
* Group root = new Group();
* Scene scene = new Scene(root, 200, 150);
* scene.setFill(Color.LIGHTGRAY);
*
* Circle circle = new Circle(60, 40, 30, Color.GREEN);
*
* Text text = new Text(10, 90, "JavaFX Scene");
* text.setFill(Color.DARKRED);
*
* Font font = new Font(20);
* text.setFont(font);
*
* root.getChildren().add(circle);
* root.getChildren().add(text);
* stage.setScene(scene);
* stage.show();
* }
*
* public static void main(String[] args) {
* Application.launch(args);
* }
* }
*
*
* The above example will generate the following image:
*
* 
*
* Coordinate System and Transformations
*
* The {@code Node} class defines a traditional computer graphics "local"
* coordinate system in which the {@code x} axis increases to the right and the
* {@code y} axis increases downwards. The concrete node classes for shapes
* provide variables for defining the geometry and location of the shape
* within this local coordinate space. For example,
* {@link javafx.scene.shape.Rectangle} provides {@code x}, {@code y},
* {@code width}, {@code height} variables while
* {@link javafx.scene.shape.Circle} provides {@code centerX}, {@code centerY},
* and {@code radius}.
*
* Any {@code Node} can have transformations applied to it. These include
* translation, rotation, scaling, or shearing transformations. A transformation
* will change the position, orientation, or size of the coordinate system as
* viewed from the parent of the node that has been transformed.
*
* See the {@link javafx.scene.Node Node} class for more information on transformations.
*
* Bounding Rectangle
*
* Since every {@code Node} has transformations, every Node's geometric
* bounding rectangle can be described differently depending on whether
* transformations are accounted for or not.
*
* Each {@code Node} has the following properties which
* specifies these bounding rectangles:
*
*
*
* - {@code boundsInLocal} – specifies the bounds of the
* {@code Node} in untransformed local coordinates.
*
* - {@code boundsInParent} – specifies the bounds of the
* {@code Node} after all transformations have been applied.
* It is called "boundsInParent" because the
* rectangle will be relative to the parent's coordinate system.
*
* - {@code layoutBounds} – specifies the rectangular bounds of
* the {@code Node} that should be used as the basis for layout
* calculations, and may differ from the visual bounds of the node. For
* shapes, Text, and ImageView, the default {@code layoutBounds} includes
* only the shape geometry.
*
*
*
* See the {@link javafx.scene.Node Node} class for more information on bounding rectangles.
*
* CSS
*
* The JavaFX Scene Graph provides the facility to style nodes using
* CSS (Cascading Style Sheets).
* The {@link javafx.scene.Node Node} class contains {@code id}, {@code styleClass}, and
* {@code style} variables are used by CSS selectors to find nodes
* to which styles should be applied. The {@link javafx.scene.Scene Scene} class contains
* the {@code stylesheets} variable which is a sequence of URLs that
* reference CSS style sheets that are to be applied to the nodes within
* that scene.
*
* For further information about CSS, how to apply CSS styles
* to nodes, and what properties are available for styling, see the
* CSS Reference Guide.
*/
package javafx.scene;