The method __________ sets the background color to yellow in JFrame frame. – Online Homework Help

DOWNLOAD: The method __________ sets the background color to yellow in JFrame frame. – Online Homework Help

Question 1 

The method __________ sets the background color to yellow in JFrame frame.

Question 1 options:

setBackground(Color.yellow)

frame.setBackGround(Color.yellow)

frame.setBackground(Color.YELLOW)

setBackground(Color.YELLOW)

Save

Question 2 

What layout manager should you use so that every component occupies the same size in the container?

Question 2 options:

GridLayout

BorderLayout

any layout

FlowLayout

Save

Question 3 (5 points)

Which of the following statements is for terminating the program when closing the frame?

Question 3 options:

frame.setDefaultCloseOperation(null)

frame.setDefaultCloseOperation(JFrame.STOP_ON_CLOSE)

frame.setDefaultCloseOperation(JFrame.TERMINATE_ON_CLOSE)

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)

Save

Question 4 (5 points)

Which of the following statements about containers is correct?

Question 4 options:

A frame can be placed inside a panel

A frame can be placed inside a frame

Both frames and panels can be placed inside a panel

A panel can be placed inside a panel

Save

Question 5 (5 points)

Which method call puts the string “Result” into the TextField named result?

Question 5 options:

result.setText(“Result”)

result.findText()

result.newText(“Result”)

result.text(“Result”)

Save

Question 6 (5 points)

How many items can be added into a JComboBox object?

Question 6 options:

Unlimited

1

0

2

Save

Question 7 (5 points)

What kind of object is used group radio buttons?

Question 7 options:

ButtonGroup

ContainerGroup

Group

JButtonGroup

Save

Question 8 (5 points)

Which of the following method calls is used to prevent the user from modifying a text field tf?

Question 8 options:

tf.setUneditable()

tf.setChangable(false);

tf.setEditable(false);

tf.preventMdification()

Save

Question 9 (5 points)

When you want to allow the user to select only one of several choices, which you use?

Question 9 options:

Ordinary buttons

Radio buttons

Check boxes

Text fields

Save

Question 10 (5 points)

What is the benefit of using layout managers?

Question 10 options:

It makes the program run much faster

It reduces the amount of memory necessary to store the window components

It defines how components of a window should be arranged when it is resized

It reduces the amount of code needed

Save

Question 11 (5 points)

Which of the following true about source and listener objects?

Question 11 options:

Both objects must be of the same type

The objects must always be of different types

They can be the same object

They must always be different objects

Save

Question 12 (5 points)

Which of the following statements is incorrect?

Question 12 options:

The listener object must be registered by the source object

The listener object’s class must implement the corresponding event-listener interface

A listener may listen for multiple sources

A source object can only have one listener object

Save

Question 13 (5 points)

Given the code below, indicate which statement describes its behavior.

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Quiz3A extends JFrame implements ActionListener

{

public Quiz3A()

{

JButton okButton = new JButton(“OK”);

add(okButton);

}

public void actionPerformed(ActionEvent e)

{

System.out.println(“The OK button is clicked”);

}

public static void main(String[] args)

{

JFrame frame = new Quiz3A();

frame.setSize(300, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setVisible(true);

}

}

Question 13 options:

The actionPerformed method is not executed when you click the OK button, because no instance of Quiz3A is registered with okButton

The program has a compilation error because no listeners are registered for okButton

The program has a runtime error because no listeners are registered with okButton

The message The OK button is clicked is displayed when you click the OK button

Save

Question 14 (5 points)

The listener for an button event is an instance of ________.

Question 14 options:

ItemListener

ActionListener

KeyListener

MouseListener

Save

Question 15 (5 points)

Which of the following statements registers a panel object aPanel as a listener for a button variable aButton?

Question 15 options:

aPanel.addEventListener(aPanel);

aButton.addActionListener(aPanel);

aButton.addActionEventListener(aPanel);

addActionListener(aPanel);

Save

Question 16 (5 points)

In the program below, which object is listening for the events of okButton?

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Quiz3B extends JFrame implements ActionListener

{

private JButton okButton = new JButton(“OK”);

public Quiz3B()

{

add(okButton);

okButton.addActionListener(this);

}

public void actionPerformed(ActionEvent e)

{

System.out.println(“The OK button is clicked”);

}

public static void main(String[] args)

{

JFrame frame = new Quiz3B();

frame.setSize(300, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setVisible(true);

}

}

Question 16 options:

JButton

frame

okButton

An anonymous object

Save

Question 17 (5 points)

What is the benefit of using adapter classes rather than listeners interfaces?

Question 17 options:

It makes it possible to respond to several events at the same time

It makes it unnecessary to implement unused event handling methods

It enables multiple inheritance of classes

It makes the response time for responding to events much quicker

Save

Question 18 (5 points)

In the program below, which object is listening for the events of okButton?

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Quiz3C extends JFrame

{

private JButton okButton = new JButton(“OK”);

public Quiz3C()

{

add(okButton);

okButton.addActionListener(

new ActionListener()

{

@Override

public void actionPerformed(ActionEvent ae)

{

System.out.println(“The OK button is clicked”);

}

});

}

public static void main(String[] args)

{

JFrame frame = new Quiz3C();

frame.setSize(300, 300);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setVisible(true);

}

}

Question 18 options:

frame

JButton

okButton

An anonymous object

Save

Question 19 (5 points)

Which of the following will occur if you fail to register an object as a listener for the click events of a button?

Question 19 options:

A compilation error will occur

Nothing will happen when the button is clicked

A class cast exception will be thrown at run-time

The containing frame will be considered as the default listener

Save

Question 20 (5 points)

When a mouse event is generated how is the location of the click point determined?

Question 20 options:

It is extracted from the mouse event that is passed to the event handler

The event handler must generate a secondary event to obtain the location

It is automatically saved as an instance variable in the object of which the mouse was clicked

It is obtained by calling a method of the mouse object