defaultcontainer.java

Java 3D Desktop Environment旨在使用Java 3D来创建一个3D桌面环境。功能包括：分布式的应用程序

package org.j3de.ui.impl; 

import java.rmi.RemoteException;

import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.event.EventListenerList;

import javax.media.j3d.BranchGroup;
import javax.media.j3d.Group; 
import javax.media.j3d.Node; 
import javax.media.j3d.TransformGroup;
import javax.media.j3d.Transform3D;

import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;

import org.j3de.exception.ExceptionHandler; 
import org.j3de.ui.LayoutManager3D;
import org.j3de.ui.LayoutConstraint;
import org.j3de.ui.UIContainer;
import org.j3de.ui.UIElement;
import org.j3de.ui.UILocalElement;
import org.j3de.ui.UIElementMapper;
import org.j3de.ui.Skin;
import org.j3de.ui.Skinable;
import org.j3de.ui.SkinException;
import org.j3de.ui.skin.SkinLayoutManagerUnconstrained;

public class DefaultContainer implements UILocalElement, Skinable {   
  private BranchGroup     bg;
  private Class           layoutManagerClass;
  private LayoutManager3D layoutManager;
  private UILocalElement  localElement;
  private RemoteContainer remoteContainer;
  private UIElementMapper elementMapper;                         
  private Skin            skin;
  private BoundsChangeHelper boundsHelper;

  private ChangeListener boundsChangeListener = new ChangeListener() {
      public void stateChanged(ChangeEvent e) {
        updateBounds();
      }
    };

  public DefaultContainer(UIElementMapper elementMapper) {    
    this.elementMapper  = elementMapper;
    this.layoutManagerClass = SkinLayoutManagerUnconstrained.class;
    
    boundsHelper = new BoundsChangeHelper(this);

    bg = new BranchGroup();  
    bg.setCapability(Group.ALLOW_CHILDREN_READ);
    bg.setCapability(Group.ALLOW_CHILDREN_WRITE);
    bg.setCapability(Group.ALLOW_CHILDREN_EXTEND);     
    bg.setBoundsAutoCompute(false);
    bg.setCapability(BranchGroup.ALLOW_BOUNDS_WRITE);
    bg.setCapability(BranchGroup.ALLOW_BOUNDS_READ);
     
    remoteContainer = getRemoteContainer();  
  }  
    
  public void setSkin(Skin skin) throws SkinException {
    this.skin = skin;
    layoutManagerChanged();
  }
  
  private void layoutManagerChanged()  {
    if (layoutManager != null)
      layoutManager.removeBoundsChangeListener(boundsChangeListener);

    try {
      layoutManager = skin.getLayoutManager(layoutManagerClass);
    } catch (SkinException e) {
      // we didn't get a layoutmanager. perhaps the previous one is
      // valid, so log error and try to continue without changing the
      // layoutmanager
      ExceptionHandler.handleException(e);
      layoutManager.addBoundsChangeListener(boundsChangeListener);
      return;
    }

    // TODO : UIELements have to be moved from old to new LayoutManager
    // Currently all elements disappear
    for (int i=0; i<bg.numChildren(); i++) {
      if (bg.getChild(i) instanceof LayoutManager3D)
        bg.removeChild(i);
    }

    layoutManager.setElementMapper(elementMapper);

    bg.addChild(layoutManager);
    
    // Add BoundsChangeListener to the layoutManager
    layoutManager.addBoundsChangeListener(boundsChangeListener);
    
    updateBounds();
  }
  
  protected RemoteContainer getRemoteContainer() {   
    return new RemoteContainer();
  }    
  
  public Node getNode() {
    return bg;
  }
  
  public UIElement getRemoteElement() {  
    return remoteContainer; 
  }

  private void updateBounds() {
    bg.setBounds(layoutManager.getBounds());
     boundsHelper.updateBounds();
  }

  public void addBoundsChangeListener(ChangeListener listener) {
    boundsHelper.addBoundsChangeListener(listener);
  }

  public void removeBoundsChangeListener(ChangeListener listener) {
    boundsHelper.removeBoundsChangeListener(listener);
  }
   
  protected class RemoteContainer implements UIContainer {
    public void add(UIElement element) throws RemoteException {        
      layoutManager.add(element);
    }
    
    public void remove(UIElement element) throws RemoteException { 
      layoutManager.remove(element);
    }
    
    public void setLayoutManager(Class layoutManagerClass) {
      DefaultContainer.this.layoutManagerClass = layoutManagerClass;
      DefaultContainer.this.layoutManagerChanged();
    } 
                
  }
 
}