Grinding4.java

package GUITools;
import GUITools.Tooltip;
import java.AWT.*;
import java.AWT.event.*;

/**
 * The Hints class was developed to encapsulate the Tooltip class
 * This class draws a yellow label tooltip (or hint/hovering help...).
 * This class takes care of all the tooltip showing and hideing events.
 * This class was developed to run under JDK 1.1.1, with very little assistance
 * from VisualAge for Java, most of the work was done using javac.
 * This class was written by Shai Almog 5/4/97. The sorce is in the public
 * domain and may be modified and used freely. It is not a requirment but
 * I would consider it good manners if you credit me and EDM/2 (www.edm2.com)
 * in applications in which this code was used ;-)
**/
class Hints extends Component implements MouseListener
{
        /**
         * The constructor accepts the following parameters:
         * displayArea - The Container where the tooltip will show on, this has to be
         * the same place where the Component is (this is a slight limitation).
         * hintOwner - The Component to which the tooltip refers.
         * textFont - The font used in the tooltip.
         * hintText - The text of the tooltip.
         * orientation - A constant (one of those defined below) referring to the location
         * of the tooltip relatively to the Component.
        **/
        public Hints(Container displayArea,Component hintOwner,Font textFont,
                     String hintText,int orientation)
        {
               this.orientation = orientation;
               this.hintText = hintText;
               this.hintOwner = hintOwner;
               this.displayArea = displayArea;
               setFont(textFont);
               hintOwner.addMouseListener(this);
        }

        public void setBackColor(Color c)
        {
               backColor = c;
        }

        public void setTextColor(Color c)
        {
               textColor = c;
        }

        public void setFont(Font textFont)
        {
               if (textFont == null) throw (new NullPointerException("Font textFont is null!"));
               this.textFont = textFont;
        }

        /**
         * Invoked when the mouse has been clicked on a component.
         * Required by the MouseListener interface.
        **/
        public void mouseClicked(MouseEvent e)
        {
        }

        /**
         * Invoked when a mouse button has been pressed on a component.
         * Required by the MouseListener interface.
        **/
        public void mousePressed(MouseEvent e)
        {
        }

        /**
         * Invoked when a mouse button has been released on a component.
         * Required by the MouseListener interface.
        **/
        public void mouseReleased(MouseEvent e)
        {
        }

        /**
         * Invoked when the mouse enters a component.
         * Required by the MouseListener interface.
        **/
        public void mouseEntered(MouseEvent e)
        {
               calculateXY();
               tooltipInstance = new Tooltip(hintText,textFont,displayArea,x,y);
               tooltipInstance.paint(displayArea.getGraphics());
        }

        /**
         * Invoked when the mouse exits the component.
         * Required by the MouseListener interface.
        **/
        public void mouseExited(MouseEvent e)
        {
               tooltipInstance.dispose();
               tooltipInstance = null;
               displayArea.repaint();
        }

        /**
         * This method calculates the X and Y where the Tooltip should be drawn
         * considering the orientation and the font size.
        **/
        private void calculateXY()
        {
               FontMetrics fontSize = getToolkit().getFontMetrics(textFont);
               int fontWidth = fontSize.stringWidth(hintText);
               int fontHeight = fontSize.getHeight();
               switch(orientation)
               {
                      case TOP_LEFT:
                      {
                              x = hintOwner.getLocation().x - fontWidth;
                              y = hintOwner.getLocation().y - fontHeight;
                              break;
                      }
                      case TOP:
                      {
                              x = hintOwner.getLocation().x - fontWidth;
                              y = hintOwner.getLocation().y;
                              break;
                      }
                      case TOP_RIGHT:
                      {
                              x = hintOwner.getLocation().x + hintOwner.getSize().width;
                              y = hintOwner.getLocation().y - fontHeight;
                              break;
                      }
                      case LEFT:
                      {
                              x = hintOwner.getLocation().x - fontWidth;
                              y = hintOwner.getLocation().y + (hintOwner.getSize().height / 2)
                                           - fontHeight;
                              break;
                      }
                      case RIGHT:
                      {
                               x = hintOwner.getLocation().x + hintOwner.getSize().width;
                               y = hintOwner.getLocation().y + (hintOwner.getSize().height / 2)
                                               - fontHeight;
                               break;
                      }
                      case BOTTOM_RIGHT:
                      {
                               x = hintOwner.getLocation().x + hintOwner.getSize().width;
                               y = hintOwner.getLocation().y + hintOwner.getSize().height;
                               break;
                      }
                      case BOTTOM_LEFT:
                      {
                               x = hintOwner.getLocation().x - fontWidth;
                               y = hintOwner.getLocation().y + hintOwner.getSize().height;
                               break;
                      }
                      case BOTTOM:
                      {
                               x = hintOwner.getLocation().x;
                               y = hintOwner.getLocation().y + hintOwner.getSize().height;
                               break;
                      }
               }
        }

        private int x,y; // The x and y location where the hint will be
                         // displayed (relative to the container).
        private Color backColor = Color.yellow,  // The background color of the hint.
                      textColor = Color.black;   // The text color of the hint.
        private Font textFont; // The font of the hint.
        private Tooltip tooltipInstance = null; // The tooltip that will be used.
        private String hintText; // The text of the hint.
        private Container displayArea; // The area contains the hintOwner where
                                       // the label will be displayed.
        private Component hintOwner;   // The Component to which this hint refers
        private int orientation = 0;
        public static final int TOP_LEFT = 1; // These are all the possible
        public static final int TOP = 2;      // orientation values.
        public static final int TOP_RIGHT = 3;
        public static final int LEFT = 4;
        public static final int RIGHT = 5;
        public static final int BOTTOM_RIGHT = 6;
        public static final int BOTTOM_LEFT = 7;
        public static final int BOTTOM = 8;
}