Question 1

Which container is used to group multiple user-interface components together?
A) text area
B) table
C) panel
D) rectangle

Accepted Answer

A panel is a container used to group multiple user-interface components together. A text area is typically used for displaying or entering a large amount of text. A table is used to display data in a tabular format. A rectangle is a graphical shape that can be used to draw or fill a region on a graphical user interface.

Question 2

Which of the following is an event source?
A) A JButton object.
B) An event listener.
C) An inner class.
D) An event adapter.

Accepted Answer

An event source is an object that generates an event, such as a JButton object that generates an action event when it is clicked. An event listener is an object that receives and processes events generated by an event source. An inner class or event adapter may be used to implement an event listener, but they are not themselves event sources.

Question 3

What is the nickname for the graphical user interface library in Java?
A) Applet
B) GUI
C) JComponent
D) Swing

Accepted Answer

Swing is the nickname for the graphical user interface library in Java. Applet refers to a program that runs in a web browser, GUI is a generic term for any graphical user interface, and JComponent is a class that is used in creating GUI components in Java.

Question 4

Which statement should be added to this code fragment to ensure that the frame is shown?
JFrame frame = new JFrame();
A) frame.setVisible(true);
B) frame.visible = true;
C) JFrame.setVisible();
D) frame.setVisible();

Accepted Answer

To display a JFrame, you need to call the setVisible(true) method on the frame object.

Question 5

A/an ____ object contains methods that describe the actions to be taken when a user clicks a user-interface graphical object.
A) Event listener
B) Event source
C) Action listener
D) Action method

Accepted Answer

An event listener is an object that contains methods that describe the actions to be taken when a user clicks a user-interface graphical object.

Question 6

Place drawing instructions inside the __________ method, which is called whenever the component needs to be repainted.
A) paintComponent
B) draw
C) paint
D) drawComponent

Accepted Answer

The correct method to place drawing instructions inside is paintComponent. This method is automatically called whenever the component needs to be repainted and provides a Graphics object as a parameter, which can be used to perform drawing operations. Choice B (draw) is not a valid method in Swing components. Choice C (paint) is a method in the AWT (Abstract Window Toolkit) but it is not commonly used in Swing. Choice D (drawComponent) is not a valid method.

Question 7

To associate an event listener with a JButton component, you must use the ___ method of the JButton class.
A) addEventListener
B) addActionListener
C) addButtonListener
D) addListener

Accepted Answer

The correct method to use to associate an event listener with a JButton component is the addActionListener method of the JButton class. This method allows you to add an ActionListener object that will be notified when the button is clicked.

Question 8

When an event occurs, the event source notifies all associated ____.
A) components
B) panels
C) interfaces
D) event listeners

Accepted Answer

When an event occurs, the event source notifies all associated event listeners. The event listeners are typically registered on the event source (e.g. button, text field, etc.) and respond to the event notification by executing some specific code or actions. Therefore, option D is the correct answer.

Question 9

Which of the following statements should be added to this code fragment to set the frame size to a width of 400 and a height of 200?
Final int FRAME_WIDTH = 400;
Final int FRAME_HEIGHT = 200;
JFrame frame = new JFrame();
A) frame.size = (FRAME_WIDTH, FRAME_HEIGHT);
B) frame.addSize(FRAME_WIDTH, FRAME_HEIGHT);
C) frame.setSize(FRAME_WIDTH, FRAME_HEIGHT);
D) frame.setSize(FRAME_HEIGHT, FRAME_WIDTH);

Accepted Answer

The method to set the size of the JFrame is "setSize" and it takes two arguments for width and height respectively. Therefore, the correct statement to set the frame size to a width of 400 and a height of 200 is "frame.setSize(FRAME_WIDTH, FRAME_HEIGHT)".

Question 10

Based on the following statement, which of the following statements sets the title of the frame:
JFrame frame = new JFrame();
A) frame.title = "An Empty Frame";
B) frame.setTitle(JFrame.EMPTY);
C) frame.addTitle("An Empty Frame");
D) frame.setTitle("An Empty Frame");

Accepted Answer

The method to set the title of a JFrame object is called "setTitle()", and option D correctly uses this method to set the title to "An Empty Frame".

Question 11

To respond to a button event, a listener must supply instructions for the ____ method of the ActionListener interface.
A) actionEvent
B) actionPerformed
C) eventAction
D) eventResponse

Accepted Answer

The correct method name to respond to a button event in the ActionListener interface is actionPerformed.

Question 12

Complete the following statement to construct a circle.
Graphics g;
g.____________________(x, y, width, height);
A) drawCircle
B) drawOval
C) fillCircle
D) DrawOval

Accepted Answer

The drawOval() method should be used as it allows creating both circles and ovals by specifying the width and height to be equal.

Question 13

When added to the code below, which statement will set the color of the next item drawn to green?
Public class ItalianFlagComponent extends JComponent
{
Public void paintComponent(Graphics g) {
g.drawRect(100, 100, 30, 60);
) . .
____________________________
) . .
}
}
A) g.setColor(GREEN);
B) g.setColor(0, 255, 0);
C) g.setColor(Color.GREEN);
D) g.setColor("GREEN");

Accepted Answer

The correct syntax to set the color of the next item drawn is g.setColor(Color color). "Color.GREEN" is a valid way to specify the color green in Java, so the correct statement to set the color to green is g.setColor(Color.GREEN).

Question 14

Which of the following statements about events and graphical user interface programs is true?
A) Your program must indicate the specific types of events to which it wishes to respond.
B) Your program will automatically receive notifications about all events that have occurred.
C) Your program must respond to notifications of all types of events that are sent to it while it is running.
D) Your program must override the default methods to handle events.

Accepted Answer

In graphical user interface programs, the program must indicate the specific types of events it wishes to respond to, and it must override the default methods to handle those events. The program will not automatically receive notifications about all events that have occurred, and it does not need to respond to notifications of event types it has not indicated a desire to handle.

Question 15

The methods of a/an ____ describe the actions to be taken when an event occurs.
A) event source
B) event listener
C) event interface
D) action source

Accepted Answer

The answer of The methods of a/an ____ describe the...

Question 16

Consider the following code snippet:
JPanel panel = new JPanel();
JFrame frame = new JFrame();
JButton button = new JButton("Click me");
JLabel label = new JLabel("Show the answer");
Frame.add(label);
Frame.add(button);
Panel.add(frame);
Which of the following statements is true?
A) This code will correctly build the user interface.
B) The button and label should be added to the panel first, and then the panel should be added to the frame.
C) The frame should be added to the panel before adding the button and label to the frame.
D) The panel should be added to the frame first, and then the button and label should be added to the panel.

Accepted Answer

The answer of Consider the following code snippet:
JPanel panel =...

Question 17

When drawing complex shapes, provide a(n) ____ to set the position of the shape.
A) constructor
B) viewer
C) component
D) frame

Accepted Answer

The answer of When drawing complex shapes, provide a(n) ____...

Question 18

Which of the following statements about listener classes is true?
A) A listener class can be declared as an anonymous inner class.
B) A listener class cannot be declared as an inner class.
C) A listener class must be declared as an inner class.
D) A listener class must be declared as an anonymous inner class.

Accepted Answer

A listener class can be declared as an anonymous inner class. This is a common practice in Java programming. An anonymous inner class is a class without a name, which is defined and instantiated in a single expression. It is often used when the class being created is used just once, so it is not necessary to give it a name. This makes the code more concise and readable.

Question 19

____ are generated when the user presses a key, clicks a button, or selects a menu item.
A) Listeners
B) Interfaces.
C) Events.
D) Errors.

Accepted Answer

Events are actions that are triggered by the user, such as clicking a button or selecting a menu item. These events are then handled by event handlers, which perform certain actions in response to the event. The other options, Listeners and Interfaces, are related to programming concepts but do not specifically refer to user actions. Errors are a type of exception that occurs when there is a problem with the code.

Question 20

Which of the following statements will compile without error?
A) public interface AccountListener()
{
Void actionPerformed(AccountEvent event);
}
B) public interface AccountListener()
{
Void actionPerformed(AccountEvent);
}
C) public interface AccountListener
{
Void actionPerformed(AccountEvent event);
}
D) public abstract AccountListener
{
Void actionPerformed(AccountEvent event);
}

Accepted Answer

Option C is the only one with the correct syntax for defining an interface. It does not include parentheses after the interface name, the return type (Void) is lowercase, and the parameter in the method definition is properly named. Option A and B have incorrect syntax due to the parentheses and lowercase "void". Option D is attempting to define an abstract class, not an interface.

Quiz 10: Graphical User Interfaces

Which container is used to group multiple user-interface components together?

Which of the following is an event source?

What is the nickname for the graphical user interface library in Java?

Which statement should be added to this code fragment to ensure that the frame is shown? JFrame frame = new JFrame() ;

A/an ____ object contains methods that describe the actions to be taken when a user clicks a user-interface graphical object.

Place drawing instructions inside the __________ method, which is called whenever the component needs to be repainted.

To associate an event listener with a JButton component, you must use the ___ method of the JButton class.

When an event occurs, the event source notifies all associated ____.

Which of the following statements should be added to this code fragment to set the frame size to a width of 400 and a height of 200? Final int FRAME_WIDTH = 400; Final int FRAME_HEIGHT = 200; JFrame frame = new JFrame() ;

Based on the following statement, which of the following statements sets the title of the frame: JFrame frame = new JFrame() ;

To respond to a button event, a listener must supply instructions for the ____ method of the ActionListener interface.

Complete the following statement to construct a circle. Graphics g; g.____________________(x, y, width, height) ;

When added to the code below, which statement will set the color of the next item drawn to green? Public class ItalianFlagComponent extends JComponent { Public void paintComponent(Graphics g) { g.drawRect(100, 100, 30, 60) ; ) . . ____________________________ ) . . } }

Which of the following statements about events and graphical user interface programs is true?

The methods of a/an ____ describe the actions to be taken when an event occurs.

Consider the following code snippet: JPanel panel = new JPanel() ; JFrame frame = new JFrame() ; JButton button = new JButton("Click me") ; JLabel label = new JLabel("Show the answer") ; Frame.add(label) ; Frame.add(button) ; Panel.add(frame) ; Which of the following statements is true?

When drawing complex shapes, provide a(n) ____ to set the position of the shape.

Which of the following statements about listener classes is true?

____ are generated when the user presses a key, clicks a button, or selects a menu item.

Which of the following statements will compile without error?