cis 461 hw1p1

package hw461;

/**
 * Please do not modify this file!!!
 */

/**
 * CIS 461: Formal Methods for Software Engineering
 * FM Radio Demonstration
 * The radio project class: DisplayPanel.java
 *
 * @author Haiping Xu
 * Revised on Sept. 15, 2016
 **/


import java.awt.*;
import javax.swing.JPanel;

public class DisplayPanel extends JPanel {
    private static final long serialVersionUID = 1L;
    private boolean on = false;
    private float frequency = 108;
    private String title;

    private Font f1 = new Font("Helvetica",Font.BOLD,36);
    private Font f2 = new Font("Times",Font.ITALIC+Font.BOLD,24);

    public DisplayPanel(String title) {
        this.title = title;
        setBackground(Color.green);
    }

    public void setValue(float value){
        this.frequency = value;
        repaint();
    }

    public boolean isOn() {
        return on;
    }

    public void turnOn() {
        on = true;
        repaint();
    }

    public void turnOff() {
        on = false;
        repaint();
    }

    public void paintComponent(Graphics g) {
        g.setColor(Color.green);
        g.fillRect(0, 0, getWidth(), getHeight());

        // Display the title
        g.setFont(f2);
        g.setColor(Color.black);
        FontMetrics fm = g.getFontMetrics();
        int fontWidth = fm.stringWidth(title);
        int fontHeight = fm.getHeight();
        int x = (getSize().width - fontWidth)/2;
        int y = fontHeight;
        g.drawString(title, x, y);
        g.drawLine(x, y+3, x+fontWidth, y+3);

        // Display the content
        g.setFont(f1);
        g.setColor(Color.red);
        fm = g.getFontMetrics();
        String content;
        if (!on) content = "----";
        else content = String.valueOf(Math.round(frequency*10)/10.0) + " MHz";
        fontWidth = fm.stringWidth(content);
        fontHeight = fm.getHeight();
        x = (getSize().width - fontWidth)/2;
        y = (getSize().height + fontHeight)/2;
        g.drawString(content, x, y);
    }
}