• Click the Change Swatch button and see one of SIX new colors chosen.
• Drag the Color Swatch rectangle and drop it on top of one of the bottom row of three rectangles.
• That will cause the dropped on rectangle to get the Swatches current color, if your onMouseRelease point was within one of the three rectangles, i.e. .contains(point) method is used, right?

1. Describe exactly what is happening in English and then go look at the code. It should help you understand part B of the Laundry program better, and suggest ideas for how to get that finished up.

2. Here is the Java code...

   import objectdraw.*;
   import java.awt.*;
   
   public class ColorDragging extends WindowController
   {
      private Location lastPoint;
   
      private FilledRect rectA, 
                         rectB,
                         rectC,
                         rectColorSwatch,
                         rectForColoring,
                         changeColorButton;
   
      private boolean draggingSwatch;   // Dragging dirty laundry item hint...
   
      private int currentSwatchColorIndex;
   
      private RandomIntGenerator generator;
   
      private static final int    RED = 1;
      private static final int PURPLE = 2;
      private static final int ORANGE = 3;
      private static final int   BLUE = 4;
      private static final int   CYAN = 5;
      private static final int YELLOW = 6;
   
      private static final int RECT_WIDTH = 100;
      private static final int RECT_HEIGHT = 50;
   
      private static final Location COLOR_SWATCH_LOCATION = 
                                                       new Location(150, 100);
      public void begin()
      {
         generator = new RandomIntGenerator(1, 6);
   
         rectA = new FilledRect(25, 200, RECT_WIDTH, RECT_HEIGHT, canvas);
         rectB = new FilledRect(150, 200, RECT_WIDTH, RECT_HEIGHT, canvas);
         rectC = new FilledRect(275, 200, RECT_WIDTH, RECT_HEIGHT, canvas); 
   
         rectColorSwatch = new FilledRect(COLOR_SWATCH_LOCATION,
                                          RECT_WIDTH, RECT_HEIGHT, canvas);    
    
         currentSwatchColorIndex = generator.nextValue();
         rectColorSwatch.setColor( whatColor(currentSwatchColorIndex) );
   
         changeColorButton = new FilledRect(100, 20, RECT_WIDTH * 2, 25, canvas);
         changeColorButton.setColor( Color.lightGray );
   
         Text t = new Text( "Change Swatch Color", 140, 25, canvas );
         t.setBold();
         t.setColor( Color.blue );
   
         Line hr = new Line(45, 280, 340, 280, canvas);
         hr.setColor( Color.orange );
   
         hr = new Line(45, 298, 340, 298, canvas);
         hr.setColor( Color.orange );
   
         new Text("Drag the swatch to any rectangle to change its color!",
                  50, 280, canvas);
   
         t = new Text("Color Swatch", 163, 114, canvas);
         t.setBold();
      }
   
      public void onMousePress(Location point)
      {
          draggingSwatch = rectColorSwatch.contains(point);
   
          if ( rectColorSwatch.contains(point) )
          { 
             lastPoint = point;
          }
          else if (changeColorButton.contains(point))
          {
             currentSwatchColorIndex = generator.nextValue();
             rectColorSwatch.setColor( whatColor( currentSwatchColorIndex ) );
          }
      }
   
      public void onMouseDrag(Location point)
      {
         if ( draggingSwatch == true )
         {
            rectColorSwatch.move( point.getX() - lastPoint.getX(), 
                                  point.getY() - lastPoint.getY() ); 
            lastPoint = point; 
         }
      }
   
      public void onMouseRelease(Location point)
      {
          FilledRect rectForColoring;
   
          if ( draggingSwatch )
          {
             rectColorSwatch.moveTo( COLOR_SWATCH_LOCATION );     
   
             if (rectA.contains(point))
             {
                rectForColoring = rectA;
             }
             else if (rectB.contains(point))
             {
                rectForColoring = rectB;
             }
             else if (rectC.contains(point))
             {
                rectForColoring = rectC;
             }          
             else
             {
                rectForColoring = null;
                return;
             }
             rectForColoring.setColor( whatColor( currentSwatchColorIndex ) );
         }
      }
   
      private Color whatColor( int colorIndex )
      {
          if (colorIndex == RED)
          { 
             return ( Color.red );
          }
          else if (colorIndex == PURPLE)
          {
             return ( Color.magenta );
          }
          else if (colorIndex == ORANGE)
          {
             return ( Color.orange );
          }
          else if (colorIndex == BLUE)
          {
             return ( new Color(0, 0, 255) );
          }
          else if (colorIndex == CYAN)
          {
             return ( Color.cyan );
          }
          else if (colorIndex == YELLOW)
          {
             return ( new Color(255, 255, 0) );
          }
          else
          {
             return Color.black;
          }
      }
   }
   

3. It looks like we only needed ONE variable for the int randomly chosen color value, not SIX variables!