Web Design and Development MCQs with Answers
Practice important Web Design and Development MCQs with answers and explanations.
Multiple Choice Questions
Q301: In the Test class example, what is the role of setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE)?
- A: Ensures the JFrame closes when the window is closed
- B: Sets the default size of the JFrame
- C: Sets the layout manager for the JFrame
- D: Adds MyPanel to the JFrame
View Answer
A
Q302: What is the purpose of the repaint() method in Java Swing?
- A: To directly call paintComponent()
- B: To schedule a call to paint() at the appropriate time
- C: To immediately clear the component's drawing
- D: To update the component's layout
View Answer
B
Q303: Why should you avoid calling paintComponent() directly for animations?
- A: It can be called before the component is visible
- B: It may not handle repainting correctly
- C: It may lead to incorrect graphics object handling
- D: It requires manual management of painting
View Answer
B
Q304: What method should be overridden to handle custom painting in Swing components?
- A: paintBorder()
- B: paintComponent()
- C: paintChildren()
- D: repaint()
View Answer
B
Q305: In the example code, what does g.fillRect(mX, mY, 20, 20) do?
- A: Draws a filled rectangle at position (mX, mY)
- B: Draws an oval at position (mX, mY)
- C: Clears the drawing area
- D: Changes the color of the graphics object
View Answer
A
Q306: What is the role of super.paintComponent(g) in the paintComponent method?
- A: It clears previous drawings before new painting
- B: It sets the color of the graphics object
- C: It paints the component's border
- D: It updates the component's layout
View Answer
A
Q307: How is the mX and mY position updated during mouse drag events?
- A: By calling repaint()
- B: By using MouseEvent.getX() and MouseEvent.getY()
- C: By directly assigning hard-coded values
- D: By calling paintComponent()
View Answer
B
Q308: What is the purpose of the Timer class in the ball animation example?
- A: To schedule repeated updates to the ball's position
- B: To handle mouse events
- C: To change the ball's color
- D: To create a new instance of JFrame
View Answer
A
Q309: How does the actionPerformed method handle the ball's movement?
- A: By directly setting mX and mY to random values
- B: By updating the direction variables and calling repaint()
- C: By changing the JPanel size
- D: By stopping the Timer
View Answer
B
Q310: What happens if you comment out super.paintComponent(g) in the paintComponent method?
- A: Previous drawings will not be cleared
- B: The component will not be visible
- C: The component's border will not be painted
- D: The component will not respond to mouse events
View Answer
A