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Trail: Learning the Java Language
Lesson: Object-Oriented Programming Concepts

## Answers to Questions and Exercises: Object-Oriented Concepts

> ### Answers to Questions

> > 1. Question: The ClickMe applet uses `Color.red` to set the drawing color to red. What other colors can you get by name like this?
> >    Answer: `Color.black`, `Color.blue`, `Color.cyan`, `Color.darkGray`, `Color.gray`, `Color.green`, `Color.lightGray`, `Color.magenta`, `Color.orange`, `Color.pink`, `Color.white`, and `Color.yellow`

> > 2. Question: How would you specify other colors, like purple?
> >    Answer: You specify them using the RGB (red-green-blue) color model. In RGB, purple is: 0.5, 0.0, 0.5

> ### Answers to Exercises

> > To read explanations about the solutions and to run the resulting applets, see Run the ClickMe Applets.
> > 1. Exercise: Modify the applet to draw a green square instead of a red spot.
> >    Answer: Look at our solution, contained in the `ClickMeGreen.java` source file.

> > 2. Exercise: Modify the applet to display your name in purple instead of a red spot.
> >    Answer: Look at our solution, contained in the `ClickMePurple.java` source file.

> ### Answers to Extra Credit Exercises

> > To read explanations about the solutions and to run the resulting applets, see Run the ClickMe Applets.
> > 1. Exercise: Modify the applet to erase the red spot instead of redrawing the whole applet.
> >    Answer: Look at our solution, contained in the `ClickMeErase.java` source file.

> > 2. Exercise: Modify the applet to drag the red spot when the mouse is held down.
> >    Answer: Look at our solution, contained in the `ClickMeDrag.java` source file.

> > 3. Exercise: Starting with your solution to the previous exercise, change the applet into a "scribble" applet, which draws as the mouse is dragged.
> >    Answer: Look at our solution, contained in the `ClickMeScribble.java` source file.

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