JavaFX Graphic Interfaces Basics

JavaFX Interfaces Graphiques

• JavaFX is a framework and library for creating user interfaces in Java.
• It was introduced in March 2014 as the official Java GUI library.
• Development of its predecessor, Swing, was largely discontinued, except for bug fixes.
• JavaFX was designed to replace Swing and AWT.

Structure of a JavaFX Application

• A JavaFX application is composed of a hierarchy of components.
• The main application window is represented by a Stage object.
• The user interface's elements are contained in a Scene object.
• Stage and Scene are provided by the system when the application launches.
• The Scene object contains GUI elements. (Label, TextField, ListView, graphic shapes, etc.)
• Layouts (e.g. BorderPane, HBox, VBox, GridPane) organize elements.
• The start() method constructs the entire application.

JavaFX Application Structure

• The Stage is a top-level container.
• A Scene contains the visual components of an application window.
• BorderPane can arrange components in five areas.
• HBox and VBox arrange components horizontally or vertically.
• GridPane organises in a grid where components are added to cells.

Handling User Actions

• The setOnAction() method is used to register EventHandler$ActionEvent for button clicks.
• lambda expressions provide a concise way to define actions.

Style

• JavaFX uses CSS-based styles.
• Global styles are specified through setUserAgentStylesheet(), which accepts CSS file URLs.
• Default styles are Modena and Caspian.

Window Management

• The main window (stage) is centered by default.
• Methods like setX(), setY(), centerOnScreen(), setMinWidth(), setMinHeight(), setMaxWidth(), setMaxHeight(), setResizable(), and sizeToScene() control the position and size of the window.
• Other methods like setTitle(), setFullScreen(), getIcons().add() and show() manage the window further.

Creating Multiple Windows

• JavaFX allows creating multiple windows (Stage) that are independent of the primary stage for a more complex interface and user experience.

Borders, Backgrounds

• Border and BorderStroke classes create and apply borders.
• Background, BackgroundFill and BackgroundImage classes control backgrounds (filling and images).

Method Based on FXML

• XML files define UI structure (FXML).
• Components are instantiated when the application loads.
• Controllers handle UI logic (events).

Layouts

• HBox: Horizontal arrangement of components.
• VBox: Vertical arrangement of components.
• FlowPane: Arranges components horizontally or vertically, wrapping to the next line or column when necessary.
• TilePane: Displays components in a grid with equal-sized tiles.
• BorderPane: Five placement areas (top, bottom, left, right, center).
• AnchorPane: Anchors components relative to the border of the container.
• StackPane: Arranges components in a stack, with the last added one on top.
• GridPane: Organises components in a grid.

Components

• Label, Button, TextField, PasswordField, CheckBox, RadioButton, ComboBox, ListView, Spinner, DatePicker, ColorPicker, and Hyperlink are common elements in JavaFX user interfaces.
• Specific methods exist to create and use each component (e.g., setting text, adding elements to a Container element).

FXML Controllers

• FXML controller handles UI logic (events etc...).

FXML

• XML files describe the UI.
• Components are initialized when loaded (FXML-based).
• Controllers are separate Java classes for event handling, often have @FXML annotations.

Creating Dynamic Components

• Use add() (or addAll()), setAlignment() methods to structure and position components within containers like HBox, VBox, GridPane, etc.

Menus

• MenuBar : The container for menus.
• Menu: A menu container.
• MenuItem: An element in a menu.
• CheckMenuItem: A menu item with a check box.
• RadioMenuItem: A menu item to select only one choice from several.
• SeparatorMenuItem: Separates items in a menu or sub-menu
• CustomMenuItem: Allows implementing custom menu items.

Keyboard Shortcuts

• MnemonicParsing: Controls whether underscores in menu items or buttons act as keyboard shortcuts.

Custom Dialogs

• Dialog: A flexible base for customizing dialog boxes that extend Alert, TextInputDialog, and ChoiceDialog.
• initModality(), setGraphic(), getIcons() and setExpandableContent() can be used to fine-tune properties.

File Handling with FileChooser

• FileChooser : to open, choose files and save files. Subclasses include DirectoryChooser.
• Functions like showOpenDialog(), showOpenMultipleDialog(), and showSaveDialog.

Other components (DatePicker, ColorPicker)

• Individual tools for date selection (DatePicker), color choice (ColorPicker).

Explore the fundamentals of JavaFX, a powerful framework for creating intuitive user interfaces in Java applications. Learn about the structure of a JavaFX application, including the roles of Stage and Scene, as well as various layout options. This quiz will test your knowledge on JavaFX components and their functionalities.