// MatrixStarter.java
// Class that allows the program to run under an applet.
import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class MatrixStarter extends Applet implements ActionListener
{
   private Button start = new Button("Start Matrix Chain Multiplier");
   private MatrixApp ma = null;

   public void init()
   {
      start.setBackground(SystemColor.control);
      setBGColor(getParameter("background"));
      setLayout(new FlowLayout());
      add(start);
      start.addActionListener(this);
   }

   public void close()
   {
      ma.setVisible(false);
      ma.dispose();
      ma = null;
   }

   public void actionPerformed(ActionEvent ae)
   {
      if (ae.getSource() == start)
        if (ma == null)
          ma = new MatrixApp(this, true);
        else
          ma.toFront();
   }

   private void setBGColor(String background)
   {
      if ((background == null) || (background.length() != 7) ||
          (background.charAt(0) != '#'))
         setBackground(Color.white);
      else
      {
         String hexcolor, red, green, blue;
         hexcolor = background.substring(1, background.length());
         red = hexcolor.substring(0, 2);
         green = hexcolor.substring(2, 4);
         blue = hexcolor.substring(4, 6);
         setBackground(new Color(Integer.parseInt(red, 16),
                                 Integer.parseInt(green, 16),
                                 Integer.parseInt(blue, 16)));
      }
   }

}