ngstacklayout.java

Novocode的 SWT 控件框架 丰富了MDI功能

/*******************************************************************************
 * Copyright (c) 2004 Stefan Zeiger and others.
 * 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.novocode.com/legal/epl-v10.html
 * 
 * Contributors:
 *     Stefan Zeiger ([e-mail]) - initial API and implementation
 *******************************************************************************/

package com.novocode.naf.gui.layout;

import org.eclipse.swt.custom.StackLayout;
import org.eclipse.swt.widgets.*;
import org.w3c.dom.Element;

import com.novocode.naf.app.NAFException;
import com.novocode.naf.data.ModelBinding;
import com.novocode.naf.data.SizeMeasure;
import com.novocode.naf.data.SizeMeasurePair;
import com.novocode.naf.data.XMLProperty;
import com.novocode.naf.gui.SWTUtil;
import com.novocode.naf.gui.ShellWindowInstance;
import com.novocode.naf.gui.event.ChangeEvent;
import com.novocode.naf.gui.event.IChangeListener;
import com.novocode.naf.model.DefaultIntModel;
import com.novocode.naf.model.IIntModel;


/**
 * Layout creator for SWT StackLayout.
 * 
 * @author Stefan Zeiger ([e-mail])
 * @since Apr 24, 2004
 */

public class NGStackLayout extends NGLayout
{
  private SizeMeasurePair margin = new SizeMeasurePair(new SizeMeasure(0));
  private ModelBinding topModelBinding;


  @XMLProperty
  public void setMargin(SizeMeasurePair a) { this.margin = new SizeMeasurePair(a); }


  @XMLProperty("hmargin")
  public void setHorizontalMargin(SizeMeasure s) { this.margin.setHorizonal(s); }
  public SizeMeasure getHorizontalMargin() { return margin.getHorizonal(); }


  @XMLProperty("vmargin")
  public void setVerticalMargin(SizeMeasure s) { this.margin.setVertical(s); }
  public SizeMeasure getVerticalMargin() { return margin.getVertical(); }


  protected void parseNAFChildElement(Element e) throws NAFException
  {
    if("model".equals(e.getLocalName()))
    {
      ModelBinding mb = new ModelBinding(e, 0);
      if("top".equals(mb.type)) topModelBinding = mb;
    }
    else super.parseNAFChildElement(e);
  }

  
  public void assignLayout(final Composite comp, ShellWindowInstance wi) throws NAFException
  {
    int embase = SWTUtil.computeEMBase(comp);
    final StackLayout l = new StackLayout();
    l.marginWidth  = margin.getHorizonal().compute(embase);
    l.marginHeight = margin.getVertical().compute(embase);
    comp.setLayout(l);
    if(topModelBinding != null)
    {
      IIntModel model = wi.models.get(topModelBinding.id);
      if(model == null && (topModelBinding.create != ModelBinding.Create.NO))
        model = new DefaultIntModel();
      if(model != null)
      {
        final IIntModel finalModel = model;
        final Control[] ch = comp.getChildren();
        IChangeListener cl = new IChangeListener()
        {
          public void stateChanged(ChangeEvent e)
          {
            int i = finalModel.getInt();
            if(i < 0) i = 0;
            else if(i >= ch.length) i = ch.length-1;
            Control c = ch[i];
            if(l.topControl != c)
            {
              l.topControl = c;
              comp.layout();
            }
          }
        };
        SWTUtil.registerModel(comp, finalModel, cl);
        cl.stateChanged(null);
      }
    }
  }
}