/*  UIDemo.java
 *
 *  A program to illustrate some basic UI components (controls).
 *
 *  Bruce M. Bolden
 *  April 5, 1998
 *  http://www.cs.uidaho.edu/~bruceb/
 */

import java.awt.*;
import java.awt.event.*;
import corejava.*;

public class UIDemo extends CloseableFrame
    implements ActionListener
{
    static  DrawingCanvas  drawingArea;
    static  TextArea  textArea;             //  A text window
       
    
    public static void main(String[] args)
    {
        Frame f = new UIDemo("UI Demo");
        
        f.setSize(350, 300);
        f.show();
    }
    
    public void paint( Graphics g )
    {
        drawingArea.doUpdate();
    }
    
    public void actionPerformed( ActionEvent e )
    {
        /*
              Dummy method
        */

        /*
        if( e.getActionCommand().equals( "red" ) )
            drawingArea.showColor( "red" );
        else if( e.getActionCommand().equals( "green" ) )
            drawingArea.showColor( "green" );
        else if( e.getActionCommand().equals( "blue" ) )
            drawingArea.showColor( "blue" );
        */
    }

    public UIDemo(String title)
    {
        setLayout( new BorderLayout() );
        
        //  Control/Display regions
        Panel  panelCheck  = new Panel();
        Panel  panelChoice = new Panel();
        Panel  panelDraw   = new Panel();
       
           //  use grid layout to place things correctly 
        panelChoice.setLayout( new GridLayout(8,1) );
        
        //  Drawing/Information display
        drawingArea = new DrawingCanvas();
        textArea    = new TextArea( 6, 35 ); 
        panelDraw.add( drawingArea );
        panelDraw.add( textArea );
               
        //  Color check boxes (display circles)
        Label circleInfoLabel = new Label( "Show:" );
        
        final int N_COLORS = 3;
        Checkbox colorCheckbox[] = new Checkbox[N_COLORS];
        colorCheckbox[0] = new Checkbox( "red"   );
        colorCheckbox[1] = new Checkbox( "green" );
        colorCheckbox[2] = new Checkbox( "blue"  );
        
            //  create event handler
        ItemListener colorCheckBoxListener = new ItemListener()
        {
            public void itemStateChanged( ItemEvent e )
            {
                String theColor =
                    ((Checkbox)e.getItemSelectable()).getLabel() ;
                    //  set color and force redraw
                drawingArea.showColor( theColor );
                drawingArea.doUpdate();
                textArea.append( "colorChoice: " + theColor + "\n" );
            }
        };
        
            //  add components and event handler to panel
        panelCheck.add( circleInfoLabel );
        
        for( int i = 0 ; i < N_COLORS ; i++ )
        {
            colorCheckbox[i].addItemListener( colorCheckBoxListener );
            panelCheck.add( colorCheckbox[i] );
        }
        
        // Create a menu for background choices
        Label bgInfoLabel = new Label( "Background:" );
        Choice choice = new Choice();
        choice.addItem( "white" );
        choice.addItem( "red"   );
        choice.addItem( "green" );
        choice.addItem( "blue"  );
        panelChoice.add( bgInfoLabel );
        panelChoice.add( choice );
        
            //  create event handler
        ItemListener colorChoiceListener = new ItemListener()
        {
            public void itemStateChanged( ItemEvent e )
            {
                    //  set color and force redraw
                //drawingArea.showColor( (String)e.getItem() );
                drawingArea.setBackgroundColor( (String)e.getItem() );
                drawingArea.doUpdate();
                textArea.append( "Background color: " + e.getItem() + "\n" );
            }
        };
        
        choice.addItemListener( colorChoiceListener );
        
        //  add panels to the frame
        add( panelCheck,  "South" );
        add( panelChoice, "East"  );
        add( panelDraw,   "Center" );
    }
}


class DrawingCanvas extends Canvas
{
    final int dcWidth  = 250;
    final int dcHeight = 120;

    boolean  showRed   = false;
    boolean  showGreen = false;
    boolean  showBlue  = false;
    
    Color  bgColor = Color.white;    //  background color
    
    DrawingCanvas()
    {
        setSize( dcWidth, dcHeight );
    }
   
    /**  force update by calling repaint().  */ 
    public void doUpdate()
    {
        repaint();
    }
   
    /**  display selected circles    */ 
    public void paint( Graphics g )
    {
        setBackground( bgColor );
        if( showRed )
        {
            g.setColor( Color.red );
            g.fillOval( 25, 20, 50, 50 );
        }
        
        if( showGreen )
        {
            g.setColor( Color.green );
            g.fillOval( 100, 20, 50, 50 );
        }
        
        if( showBlue )
        {
            g.setColor( Color.blue );
            g.fillOval( 175, 20, 50, 50 );
        }
    }
   
    /**  set circles to be displayed   */ 
    public void showColor( String s )
    {
        if( s.equals( "red" ) )
            showRed = showRed ? false : true;
        else if( s.equals( "green" ) )
            showGreen = showGreen ? false : true;
        else if( s.equals( "blue" ) )
            showBlue = showBlue ? false : true;
    }
   
    /**  set canvas background    */ 
    public void setBackgroundColor( String s )
    {
        if( s.equals( "red" ) )
            bgColor = Color.red;
        else if( s.equals( "green" ) )
            bgColor = Color.green;
        else if( s.equals( "blue" ) )
            bgColor = Color.blue;
        else
            bgColor = Color.white;

    }
}