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Quiz
9
Swing
Components
There are
25 questions
Question 1.
A
component is
(a)
an
application object
(b)
a
class method
(c)
a
visual object with which a user can interact
(d)
a
part of an instance of a class
Question 2.
The
main superclass of swing components is...
(a) JPanel
(b) JComponent
(c) Frame
(d) Container
Question 3.
What
is the main class called from which all other classes ultimately descend?
______________________
Question 4.
Which
one of the following are components only?
(a)
Button,
Font, Label
(b)
Button,
Label, LayoutManager
(c)
Label,
Button, TextArea
(d)
Label,
Panel, Menu.
Question 5.
Which
one of the following expressions correctly sets the text color of a label to
blue?
(a) lbl.setForeground(Colour.blue);
(b) lbl.setForeground(0,0,255);
(c)
lbl.setBackground(Colour.blue);
(d) lbl.setBackground(0,0,255);
Question 6.
What
do you call a text component that cannot be modified by the user?
______________________
Question 7.
Write
down the method and parameter value you would use to make a text field or text
area uneditable.
______________________
Question 8.
Supposing
you have created a container and a component. Which method would you use
to show the component in the container?
______________________
Question 9.
Suppose
you want to take out a component from a container, which method would you
use?
______________________
Question 10.
A
panel cannot be added to another panel...
(a)
true
(b)
false
Question 11.
Write
down an expression to add a swing radio button referenced by a variable bt
to an applet.
_________________________________________________
Question 12.
Write
down an expression to add a swing combo box referenced by the variable aCombo
to a swing panel referenced by the variable mainPanel.
_________________________________________________
Question 13.
The
following statement is incorrect.
JButton
cmd = JButton("Hi everyone!");
Write
down the correct way of creating an instance of a JButton.
_________________________________________________
Question 14.
The
following statement is incorrect.
JCheckBox
= new JCheckBox ("Select Me");
Write
down a correct statement.
_________________________________________________
Question 15.
Which
of the following expression creates an action button with a caption and an
image?
(a) JButton
but1 = new JButton ();
(b) JButton
but1 = new JButton (new ImageIcon ("sun.gif"));
(c) JButton
but1 = new JButton ("hi", new ImageIcon ("sun.gif"));
(d) JButton
but1 = new JButton ("hi");
Question 16.
Checkboxes
provide a set of mutually exclusive options.
(a)
true
(b)
false
Question 17.
Radio
buttons provide a set of mutually exclusive options.
(a)
true
(b)
false
Question 18.
Write
down the name of the class used to create groups of radio buttons.
______________________
Question 19.
Write
down an expression to set the font of a text field referenced by the variable
aText to Arial, bold and size 14 points.
_________________________________________________
Question
20.
What
is the difference between a TextArea and a TextField?
(a)
A
TextArea
can handle multiple lines of text but
a TextField cannot
(b)
A
TextArea can be used for text output but aTextField cannot
(c)
A
TextArea is a class but a TextFields is an instance of a class.
(d)
You
can only draw onto TextAreas.
Question 21.
Two
of the following components displays a scrollbar if there is not enough room
to display everything. Which two?
(a)
JList
(b)
JScrollPane
(c)
JTextArea
(b)
JComboBox
Question 22.
Let's
suppose you wish to change the text displayed by a label which has already
been created. Which method would you use?
______________________
Question 23.
Let's
suppose you wish to disable an action button. Which method and
parameter value would you use?
______________________
Question 24.
Let's
suppose you wish to make a label invisible. Which method and parameter
value would you use?
______________________
Question 25.
Let's
suppose you wish to set the background color of a label referenced by the
variable anotherLabel to yellow. Write down the expression would
you use?
______________________
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