import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class week4a extends Applet
			    implements ActionListener, ItemListener
{
  final String SPATIES = "          ";
  TextField redText    = new TextField(""),
            greenText  = new TextField(""),
            blueText   = new TextField("");

  Button inverteerKnop = new Button("inverteerknop"),
         toonKnop      = new Button("toonknop");

  CheckboxGroup keuzeGroep = new CheckboxGroup();
  Checkbox keuze1Check     = new Checkbox("methode 1", keuzeGroep, true),
           keuze2Check     = new Checkbox("methode 2", keuzeGroep, false);

  List redList    = new List(17, false),
       greenList  = new List(17, false),
       blueList   = new List(17, false);

  Label roodLab   = new Label("", Label.CENTER),
        greenLab  = new Label("", Label.CENTER),
        blueLab   = new Label("", Label.CENTER),
        rgbLab    = new Label("", Label.CENTER),
        textRood  = new Label("Rood"),
        textGroen = new Label("Groen"),
        textBlauw = new Label("Blauw");
  
  public void init()
  {
    setLayout(new GridLayout(11, 2));

    //1e layout regel
    add(keuze1Check);
    keuze1Check.addItemListener(this);
    add(new Label(" "));

    //2e layout regel
    add(new Label("Rood:  0.0 - 1.0"));
    add(redText);

    //3e layout regel
    add(new Label("Groen: 0.0 - 1.0"));
    add(greenText);

    //4e layout regel
    add(new Label("Blauw: 0.0 - 1.0"));
    add(blueText);

    //5e layout regel
    add(keuze2Check);
    keuze2Check.addItemListener(this);
    add(new Label(" "));

    //6e layout regel
    add(textRood);
    add(redList);

    //7e layout regel
    add(textGroen);
    add(greenList);

    //8e layout regel
    add(textBlauw);
    add(blueList);

    //9e layout regel
    add(roodLab);
    add(greenLab);

    //10e layout regel
    add(blueLab);
    add(rgbLab);

    //11e layout regel
    add(toonKnop);
    toonKnop.addActionListener(this);
    add(inverteerKnop);
    inverteerKnop.addActionListener(this);

    //opzetten listboxen 
    for(int i=0;i<256;i+=16)
    {
      redList.addItem(Integer.toString(i));
      greenList.addItem(Integer.toString(i));
      blueList.addItem(Integer.toString(i));
    }
    redList.addItem(Integer.toString(255));
    greenList.addItem(Integer.toString(255));
    blueList.addItem(Integer.toString(255));
    
    //opzetten labels
    roodLab.setBackground(new Color(0.5f, 0.0f, 0.0f));
    greenLab.setBackground(new Color(0.0f, 0.5f, 0.0f));
    blueLab.setBackground(new Color(0.0f, 0.0f, 0.5f));
    rgbLab.setBackground(new Color(0.5f, 0.5f, 0.5f));

    //instellen interface
    redList.hide();
    greenList.hide();
    blueList.hide();

    redText.setText("0.5");
    greenText.setText("0.5");
    blueText.setText("0.5"); 
 
    redList.select(8);  
    greenList.select(8);      
    blueList.select(8);  
  }

  public void itemStateChanged(ItemEvent gebeurtenis)
  {    
    if (gebeurtenis.getSource() == keuze1Check)
    {
      redList.hide();
      greenList.hide();
      blueList.hide();
      redText.show();
      greenText.show();
      blueText.show();
    }
    else if (gebeurtenis.getSource() == keuze2Check)
    {
      redList.show();
      greenList.show();
      blueList.show();
      redText.hide();
      greenText.hide();
      blueText.hide();
    }
  }

  public void actionPerformed(ActionEvent gebeurtenis)
  {
    //er wordt op de toon- of inverteerknop gedrukt
    if (keuze1Check.getState())
    {
      float red, green, blue;

      red   = Float.valueOf(redText.getText()).floatValue();
      green = Float.valueOf(greenText.getText()).floatValue();
      blue  = Float.valueOf(blueText.getText()).floatValue();

      if (gebeurtenis.getSource() == inverteerKnop)
      {
        red   = 1.0f - red;
        green = 1.0f - green;
        blue  = 1.0f - blue;
      }

      roodLab.setBackground(new Color(red, 0 ,0));
      greenLab.setBackground(new Color(0, green, 0));
      blueLab.setBackground(new Color(0, 0, blue));
      rgbLab.setBackground(new Color(red, green, blue));

      //vul aan
    }
    else if (keuze2Check.getState())
    {
      int r, g, b;

      r = Integer.parseInt(redList.getSelectedItem());
      g = Integer.parseInt(greenList.getSelectedItem());
      b = Integer.parseInt(blueList.getSelectedItem());
 
     if (gebeurtenis.getSource() == inverteerKnop)
      {
        r = 255 - r;
        g = 255 - g;
        b = 255 - b;
      }
   
      roodLab.setBackground(new Color(r, 0, 0));
      greenLab.setBackground(new Color(0, g, 0));
      blueLab.setBackground(new Color(0, 0, b));
      rgbLab.setBackground(new Color(r, g, b));
    }
  }
}