XViewerMouseListener.java

/*******************************************************************************
 * Copyright (c) 2004, 2007 Boeing.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Boeing - initial API and implementation
 *******************************************************************************/
package org.eclipse.nebula.widgets.xviewer.util.internal;

import org.eclipse.nebula.widgets.xviewer.XViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.swt.widgets.TreeItem;

/**
 * @author Donald G. Dunne
 */
public class XViewerMouseListener implements MouseListener {

   private final XViewer xViewer;
   private MouseEvent leftClickEvent;

   public XViewerMouseListener(XViewer xViewer) {
      this.xViewer = xViewer;
   }

   @Override
   public void mouseDoubleClick(MouseEvent event) {
      Point point = new Point(event.x, event.y);
      TreeColumn column = xViewer.getColumnUnderMouseClick(point);
      TreeItem itemToReturn = xViewer.getItemUnderMouseClick(point);

      xViewer.handleDoubleClick(column, itemToReturn);
   }

   @Override
   public void mouseDown(MouseEvent event) {
      if (isLeftClick(event)) {
         leftClickEvent = event;
      }
      if (isRightClick(event)) {
         xViewer.processRightClickMouseEvent(new Point(event.x, event.y));
      }
   }

   private boolean isRightClick(MouseEvent event) {
      return event.button == 3;
   }

   @Override
   public void mouseUp(MouseEvent event) {
      TreeItem item = xViewer.getItemUnderMouseClick(new Point(event.x, event.y));
      if (item == null) {
         return;
      }

      try {
         TreeColumn column = xViewer.getColumnUnderMouseClick(new Point(event.x, event.y));
         if (column == null) {
            return;
         }
         if (isLeftClick(event) && controlNotBeingHeld(event)) {

            if (altIsBeingHeld(event)) {
               // System.out.println("Column " + colNum);
               xViewer.handleAltLeftClick(column, item);
            } else if (clickOccurredInIconArea(event, item)) {
               xViewer.handleLeftClickInIconArea(column, item);
            } else {
               // System.out.println("Column " + colNum);
               xViewer.handleLeftClick(column, item);
            }
         }
         xViewer.updateStatusLabel();
      } catch (ArrayIndexOutOfBoundsException ex) {
         // mouse clicked outside of last/valid column
         return;
      }

   }

   private boolean clickOccurredInIconArea(MouseEvent event, TreeItem item) {
      Integer columnNumber = xViewer.getColumnNumberUnderMouseClick(new Point(event.x, event.y));
      if (columnNumber == null) {
         return false;
      }
      Rectangle rect = item.getBounds(columnNumber);
      return (event.x <= (rect.x + 18));
   }

   private boolean isLeftClick(MouseEvent event) {
      return event.button == 1;
   }

   private boolean altIsBeingHeld(MouseEvent event) {
      return ((event.stateMask & SWT.MODIFIER_MASK) == SWT.ALT);
   }

   private boolean controlNotBeingHeld(MouseEvent event) {
      return !controlBeingHeld(event);
   }

   private boolean controlBeingHeld(MouseEvent event) {
      return ((event.stateMask & SWT.MODIFIER_MASK) == SWT.CTRL);
   }

   public MouseEvent getLeftClickEvent() {
      return leftClickEvent;
   }

}