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Part B - Wake Up - Display Time

In this step, we will add the display of the changing time. We will use a GregorianCalendar object to get the current time.

GregorianCalendar xday = new GregorianCalendar();
String xtime = xday.getTime().toString();

screen.drawString("DDD MMM 31 99:99:99 EDT 2008", 5,15);

screen.drawString(xtime, 5, 15);

The problem with this display is that as the time value changes, the modified value overlays what was there and it becomes unreadable.

What is needed is to erase the old time display before showing the new time display. Erase it by rewriting the old time with the current background color. Then the new time can be written on the cleared area using the desired foreground color.

String lastTime = "";

screen.setColor(getBackground());
screen.drawString(lastTime, 5, 15);

lastTime = xtime;

These changes all take place in the class DteTimePanel which now looks like the following. The rest of the code has not changed.

class DteTimePanel extends JPanel {
    String lastTime = "";

    public void paint(Graphics screen) {
        GregorianCalendar xday = new GregorianCalendar();
        String xtime = xday.getTime().toString();

	Color fgColor = new Color(40, 120, 160);
        Font type = new Font("Monospaced", Font.BOLD, 20);
        screen.setFont(type);
        screen.setColor(getBackground());
        screen.drawString(lastTime, 5, 15);
        screen.setColor(fgColor);
        screen.drawString(xtime, 5, 15);
        lastTime = xtime;
        repaint();
    }
}

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