mousehandler.java

一个用Java写的

/******************************************************************
 * Copyright (C) 2002-2006 Andrew Girow. All rights reserved.     *
 * ---------------------------------------------------------------*
 * This software is published under the terms of the TinyLine     *
 * License, a copy of which has been included with this           *
 * distribution in the TINYLINE_LICENSE.TXT file.                 *
 *                                                                *
 * For more information on the TinyLine,                          *
 * please see <http://www.tinyline.com/>.                         *
 *****************************************************************/
package com.tinyline.app;
import java.awt.event.*;
import java.awt.Graphics;
import java.awt.Color;
import java.net.URL;

import com.tinyline.svg.*;
import com.tinyline.tiny2d.*;


/**
 * This class represents the MouseListener associated with the
 * PPSVGCanvas and used for the Personal Profile SVG Player.
 * <p>
 * @author (C) Andrew Girow
 * @version 1.9
 * <p>
 */

public class MouseHandler
  implements MouseListener, MouseMotionListener
{

  /**
   * The Canvas that this mouse handler uses
   */
  PPSVGCanvas canvas;

  /**
   * Type of the MouseHandler
   */
  public static final int LINK_MOUSE      = 0;
  public static final int PAN_MOUSE       = 1;
  public static final int ZOOM_IN_MOUSE   = 2;
  public static final int ZOOM_OUT_MOUSE  = 3;

  public int type = LINK_MOUSE;

  /**
   * The original values to calculate pan.
   */
  int pressedX;
  int pressedY;
  int draggedX;
  int draggedY;


  /**
   * Constructs a Mouse Handler object with the given canvas. The
   * handler will perform some function on the canvas when it
   * is given mouse events.
   *
   * @param canvas The canvas this mouse handler is handling.
   */
  public MouseHandler(PPSVGCanvas canvas)
  {
    this.canvas = canvas;
  }


  /**
   * Invoked when the mouse has been clicked in the Canvas canvas.
   */
  public void mouseClicked(MouseEvent e)
  {
  }

  /**
   * Invoked when the mouse has been pressed in the canvas.
   */
  public void mousePressed(MouseEvent e)
  {
    if(type == PAN_MOUSE)
    {
      pressedX = e.getX();
      pressedY = e.getY();
      draggedX = pressedX;
      draggedY = pressedY;
    }
  }

  /**
   * Invoked when the mouse has been released in the canvas.
   */
  public void mouseReleased(MouseEvent e)
  {
      if(type == ZOOM_OUT_MOUSE)
      {
         SVGEvent  event = new SVGEvent(SVGEvent.EVENT_ZOOM, new TinyNumber(1));
         canvas.postEvent(event);
      }
      else if(type == ZOOM_IN_MOUSE)
      {
         SVGEvent  event = new SVGEvent(SVGEvent.EVENT_ZOOM, new TinyNumber(0));
         canvas.postEvent(event);
      }
      else if(type == LINK_MOUSE)
      {
         SVGEvent  event = new SVGEvent(SVGEvent.EVENT_CLICK, new TinyPoint(e.getX(),e.getY()) );
         canvas.postEvent(event);
      }
      else if(type == PAN_MOUSE)
      {
         SVGEvent  event = new SVGEvent(SVGEvent.EVENT_SCROLL,new TinyPoint(pressedX -e.getX(),pressedY -e.getY()));
         canvas.postEvent(event);
      }
  }

  /**
   * Invoked when the mouse has entered the canvas.
   */
  public void mouseEntered(MouseEvent e) {}

  /**
   * Invoked when the mouse has exited the canvas.
   */
  public void mouseExited(MouseEvent e) {}

  /**
   * Invoked when a mouse button is pressed within the Canvas canvas and then
   * dragged.
   */
  public void mouseDragged(MouseEvent e)
  {
     if(type == PAN_MOUSE && canvas.raster.document.isZoomAndPanAnable() )
     {
          drawXORLine(pressedX,pressedY,draggedX,draggedY);
          draggedX = e.getX();
          draggedY = e.getY();
          drawXORLine(pressedX,pressedY,draggedX,draggedY);
     }
  }

  /**
   * Invoked when the mouse button has been moved in the Canvas canvas,
   * when there are no buttons pressed.
   */
  public void mouseMoved ( MouseEvent e ) {}

  public void drawXORLine(int x0, int y0, int x1, int y1)
  {
      Graphics g = canvas.getGraphics();
      if(g!=null)
      {
         g.setXORMode(Color.white);
         g.setColor(Color.black);
         g.drawLine(x0,y0,x1,y1);
         g.dispose();
         g = null;
      }
  }

}