Java Swing Tutorial

Questions and Answers

What does the JButton constructor JButton(String s) do?

Creates a button with specified text. (correct)

Creates a button with an icon.

Creates a button that is not visible by default.

Creates a button without text or icon.

Which of the following classes does JButton extend?

ButtonGroup

Component

JComponent

AbstractButton (correct)

Which method is used to set the visibility of a component in Swing?

public void show(boolean b)

public void setState(boolean b)

public void setVisible(boolean b) (correct)

public void display(boolean b)

How can a frame be created through inheritance in Java Swing?

By extending the Frame class. Signup and view all the answers

Which of the following methods is not a commonly used method of the Component class?

public void remove(Component c) Signup and view all the answers

Which layout management method is primarily used in Swing for arranging components?

setLayout(LayoutManager m) Signup and view all the answers

What is the default visibility state of a component in Java Swing?

false Signup and view all the answers

When creating a JButton without text or icon, which constructor is used?

JButton() Signup and view all the answers

What is the primary purpose of the JButton class in Java Swing?

To act as a clickable button in an application. Signup and view all the answers

Which of the following is NOT a typical use of the JLabel class in Java Swing?

Receiving user input. Signup and view all the answers

How can JTextField be used in a Java Swing application?

To allow users to enter a single line of text. Signup and view all the answers

What interface must be implemented to handle button click events in Java Swing?

ActionListener Signup and view all the answers

Which layout manager organizes components in a top-to-bottom manner in Java Swing?

BoxLayout Signup and view all the answers

Which of the following Swing components is known to be lightweight?

JButton Signup and view all the answers

Which statement is true about ActionListener in Java Swing?

It allows for action handling of various GUI components. Signup and view all the answers

What is the primary difference in component weight between Java AWT and Swing?

Swing is lightweight while AWT is heavyweight. Signup and view all the answers

What does the method `getText()` return in a JLabel?

The text string that a label displays Signup and view all the answers

Which constructor for JTextField initializes the field with specific text and a number of columns?

JTextField(String text, int columns) Signup and view all the answers

What does the `setHorizontalAlignment(int alignment)` method do?

Sets the X-axis alignment of the label's contents Signup and view all the answers

What is the purpose of the JTextField class?

To allow editing of a single line of text Signup and view all the answers

If you want to create an empty JTextField with 10 columns, which constructor would you use?

JTextField(10) Signup and view all the answers

Which method would you use to obtain the icon currently displayed by a JLabel?

getIcon() Signup and view all the answers

What does the `int getHorizontalAlignment()` method return in a JLabel?

The alignment of the label's contents along the X axis Signup and view all the answers

Which of the following methods is not associated with JLabel?

addActionListener() Signup and view all the answers

Study Notes

Overview of Java Swing

Java Swing is part of Java Foundation Classes (JFC) for creating window-based applications.
Built on top of AWT (Abstract Windowing Toolkit) and fully written in Java.
Offers platform-independent and lightweight components.
Key classes in javax.swing package include JButton, JTextField, JTextArea, JRadioButton, JCheckbox, JMenu, and JColorChooser.

Difference between AWT and Swing

AWT components are platform-dependent; Swing components are platform-independent.
AWT components are heavyweight, while Swing components are lightweight.
AWT lacks pluggable look and feel; Swing supports pluggable look and feel.
Swing offers more extensive and advanced components like tables, lists, scroll panes, color choosers, and tabbed panes compared to AWT.
Swing adheres to the MVC (Model-View-Controller) architecture; AWT does not.

Java Foundation Classes (JFC)

JFC consists of a set of GUI components that simplify desktop application development.

Swing Class Hierarchy

The javax.swing package contains a hierarchy of classes designed for creating GUI applications.

Commonly Used Methods of Component Class

add(Component c): Adds a component to another component.
setSize(int width, int height): Sets the size of the component.
setLayout(LayoutManager m): Assigns a layout manager to the component.
setVisible(boolean b): Sets component visibility; default is false.

Frame Creation in Swing

A frame can be created through association by creating an object of the Frame class or through inheritance by extending the Frame class.
Swing code can be written within main(), constructors, or other methods.

JButton Class Overview

Declared as public class JButton extends AbstractButton implements Accessible.
Constructors:
- JButton(): Creates a button with no text and icon.
- JButton(String s): Creates a button with specified text.
- JButton(Icon i): Creates a button with a specified icon.
Common Methods:
- getText(): Returns the text string displayed by the button.
- setText(String text): Sets the text displayed by the button.
- setHorizontalAlignment(int alignment): Aligns the button's contents on the X axis.
- getIcon(): Returns the graphic image displayed by the button.
- getHorizontalAlignment(): Returns the alignment of the button's contents.

JTextField Class Overview

A JTextField is a text component that allows single-line text editing, inheriting from JTextComponent.
Declared as public class JTextField extends JTextComponent implements SwingConstants.
Constructors:
- JTextField(): Creates a new JTextField.
- JTextField(String text): Initializes a JTextField with specified text.
- JTextField(String text, int columns): Initializes with specified text and column count.
- JTextField(int columns): Creates an empty JTextField with a set number of columns.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the fundamentals of Java Swing, a part of the Java Foundation Classes (JFC) designed for creating window-based applications. Learn about its lightweight components and how it differs from AWT, as well as the key classes included in the javax.swing package, like JButton and JTextField.