ngdropdown.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;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;

import com.novocode.naf.app.*;
import com.novocode.naf.data.DataDecoder;
import com.novocode.naf.data.ModelBinding;
import com.novocode.naf.data.XMLProperty;
import com.novocode.naf.gui.event.ActionEvent;
import com.novocode.naf.gui.event.DefaultActionBroadcaster;
import com.novocode.naf.gui.event.IActionListener;
import com.novocode.naf.gui.event.ChangeEvent;
import com.novocode.naf.gui.event.IChangeListener;
import com.novocode.naf.model.DefaultItemListModel;
import com.novocode.naf.model.IItemListModel;
import com.novocode.naf.resource.NGComponent;


/**
 * A drop-down menu button.
 * 
 * @author Stefan Zeiger ([e-mail])
 * @since Dec 4, 2003
 */

public final class NGDropDown extends NGWidget implements IToolItemWidget
{
  private String text, imageResource;


  @XMLProperty public void setText(String s) { this.text = s;}
  public String getText() { return text; }
  
  
  @XMLProperty("image") public void setImageResource(String s) { this.imageResource = s; }
  public String getImageResource() { return imageResource; }


  public ToolItem createToolItem(NGToolBar parentComp, final ToolBar bar, final ShellWindowInstance wi) throws NAFException
  {
    final ToolItem item = new ToolItem(bar, SWT.DROP_DOWN);
    parentComp.addRegisteredImage(imageResource, item, wi.imageManager);
    if(text != null) item.setText(DataDecoder.decodeAccessKey(text));
    else if((bar.getStyle() & SWT.RIGHT) != 0) item.setText("");

    final IActionListener actionModel = getModel("action", wi.models);
    final ActionEvent ae = (actionModel == null) ? null : new ActionEvent(this, getModelBinding("action").getAttribute("command"), wi);
    IItemListModel itemsModel = getModel("items", wi.models);


    final Menu[] menu = new Menu[1];
    if(itemsModel != null)
    {
      final boolean[] dirty = new boolean[1];

      final IChangeListener cl = new IChangeListener()
      {
        public void stateChanged(ChangeEvent e)
        {
          dirty[0] = true;
        }
      };
      SWTUtil.registerModel(item, itemsModel, cl);

      item.addListener(SWT.Selection, new Listener ()
      {
        public void handleEvent (Event event)
        {
          if(event.detail == SWT.ARROW)
          {
            if(menu[0] == null || dirty[0])
            {
              dirty[0] = false;
              if(menu[0] != null)
              {
                //System.out.println("Disposing of dynamic menu");
                menu[0].dispose();
              }
              //System.out.println("Creating dynamic menu");
              menu[0] = new Menu (wi.getShell(true), SWT.POP_UP);
              addMenuChildren(menu[0], wi);
            }
            Rectangle rect = item.getBounds();
            Point pt = bar.toDisplay(new Point(rect.x, rect.y + rect.height));
            menu[0].setLocation(pt.x, pt.y);
            menu[0].setVisible(true);
          }
          else if(actionModel != null)
          {
            actionModel.performAction(ae);
          }
        }
      });
    }
    else // no dynamic items
    {
      menu[0] = new Menu (wi.getShell(true), SWT.POP_UP);
      item.addListener(SWT.Selection, new Listener ()
      {
        public void handleEvent (Event event)
        {
          if(event.detail == SWT.ARROW)
          {
            Rectangle rect = item.getBounds();
            Point pt = bar.toDisplay(new Point(rect.x, rect.y + rect.height));
            menu[0].setLocation(pt.x, pt.y);
            menu[0].setVisible(true);
          }
          else if(actionModel != null)
          {
            actionModel.performAction(ae);
          }
        }
      });
      addMenuChildren(menu[0], wi);
    }
    
    item.addListener(SWT.Dispose, new Listener()
    {
      public void handleEvent(Event event)
      {
        if(menu[0] != null)
        {
          menu[0].dispose();
          menu[0] = null;
        }
      }
    });

    //addModels(item, wi);
    return item;
  }


  private void addMenuChildren(Menu parent, ShellWindowInstance wi)
  {
    ModelBinding itemsModelBinding = getModelBinding("items");
    IItemListModel itemsModel = getModel("items", wi.models);
    //System.out.println("itemsModel = "+itemsModel);
    //System.out.println("itemsModelBinding.widgetListIdx = "+itemsModelBinding.widgetListIdx);

    List<NGComponent> list = getUnexpandedChildren(null);
    List<NGComponent> childList = new ArrayList<NGComponent>();
    for(int i=0; i<=list.size(); i++)
    {
      if(itemsModel != null && itemsModelBinding.widgetListIdx == i)
      {
        NGComponent[] dynamicWidgets = itemsModel.getItems();
        childList.clear();
        //System.out.println("dynamicWidgets.length = "+dynamicWidgets.length);
        for(int j=0; j<dynamicWidgets.length; j++) dynamicWidgets[j].expandSelf(childList);
        //System.out.println("childList.size() = "+childList.size());
        for(NGComponent ch : childList)
        {
          if(!(ch instanceof IMenuItemWidget))
            throw new NAFException("Cannot create a menu item from a "+ch.getClass()+" object");
          MenuItem item = ((IMenuItemWidget)ch).createMenuItem(parent, wi);
          ((NGWidget)ch).addModels(item, wi, this);
        }
      }
      if(i != list.size())
      {
        childList.clear();
        list.get(i).expandSelf(childList);
        for(NGComponent ch : childList)
        {
          if(!(ch instanceof IMenuItemWidget))
            throw new NAFException("Cannot create a menu item from a "+ch.getClass()+" object");
          MenuItem item = ((IMenuItemWidget)ch).createMenuItem(parent, wi);
          ((NGWidget)ch).addModels(item, wi, this);
        }
      }
    }
  }


  protected Object createDefaultModel(ModelBinding mb)
  {
    if("items".equals(mb.type)) return new DefaultItemListModel();
    else if("action".equals(mb.type)) return new DefaultActionBroadcaster(mb.id);
    else return super.createDefaultModel(mb);
  }
}