JavaFX Components

What are JavaFX Components?

JavaFX components are objects with a graphical interface that can be displayed in a frame, such as buttons, labels, and text fields.

What are Events in JavaFX?

Events in JavaFX represent user actions like mouse clicks or dragging the mouse. These events trigger actions in the program.

What are Handlers in JavaFX?

Handlers in JavaFX are objects that intercept and evaluate events, responding to user actions like button presses.

What is Event-Driven Programming (EDP)?

Event-driven programming is a programming model where the program is driven by events, such as user inputs, rather than sequential execution.

What are common uses of EDP?

EDP is used in GUIs, web servers, gaming engines, IoT systems, and stock trading platforms, where actions are triggered by events.

What is the basic structure of EDP?

EDP involves components (objects), events (user actions), and handlers (objects reacting to events).

What is the Scene Graph in JavaFX?

The scene graph in JavaFX represents the hierarchical structure of visual elements (stages, scenes, nodes) in an application window.

What is a Stage in JavaFX?

A stage in JavaFX is a top-level container that represents a window in a GUI application.

What is a Scene in JavaFX?

A scene in JavaFX holds the content of a window and is represented as a scene graph. Multiple scenes can be used in a single stage.

What are Nodes in JavaFX?

Nodes are components in JavaFX, such as containers and visual elements, that are part of the scene graph.

What are JavaFX Containers?

Containers in JavaFX are components used to organize and lay out other components, like VBox, HBox, and GridPane.

What is a ScrollPane in JavaFX?

A ScrollPane is a container that enables scrolling when its contents exceed the available space. It’s useful for applications like chat programs.

What is the purpose of nesting containers in JavaFX?

Nesting containers allows for the creation of complex layouts by combining different container types within each other.

What are common JavaFX components?

Common JavaFX components include Label, Button, RadioButton, ProgressBar, ToggleButton, TextArea, ScrollPane, and Slider.

What is the role of buttons in JavaFX?

Buttons in JavaFX trigger events when clicked, making them simple to use for event-driven actions.

What are Event Objects in JavaFX?

Event objects in JavaFX represent user actions, like pressing a key or clicking the mouse, which generate events to be handled.

How are actions triggered from pressing buttons in JavaFX?

To handle button presses, an event handler is added, defining the action to take when the button is clicked.

What is the EventHandler approach in JavaFX?

The EventHandler approach involves creating a class that implements EventHandler to define actions for specific events.

What are Nested Classes in Java?

Nested classes in Java are classes defined within another class. They include static nested classes, inner classes, local inner classes, and anonymous inner classes.

What are the benefits of Nested Classes?

Nested classes help group related classes together, enhance encapsulation, and improve code readability and maintainability.

What is the difference between static nested classes and inner classes in Java?

Static nested classes are defined with the static keyword, while inner classes are non-static and defined within an outer class.

What are Local Inner Classes in Java?

Local inner classes are defined within a method and are only accessible within the method where they are defined.

What are Anonymous Inner Classes in Java?

Anonymous inner classes are unnamed classes defined within a method, typically used for single-use instances, such as in event handling.

What is the Comparator interface in Java?

The Comparator interface is used to define custom sorting logic, often implemented using nested or anonymous classes.

What is the purpose of using Nested Classes for Comparators?

Nested classes provide a convenient way to group and define Comparators within the context of a class, making the code more organized.

What are the four patterns for defining Nested Classes?

The four patterns are static nested class, inner class, local inner class, and anonymous inner class.

What is an example of using Nested Classes for sorting?

A Comparator can be defined using any nested class pattern to define custom sorting behavior, such as sorting elements in an array.