ViewToolBarManager.java

/******************************************************************************* 
* Copyright (c) 2008 EclipseSource 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.eclipse.org/legal/epl-v10.html
*
* Contributors:
*   EclipseSource - initial API and implementation
*******************************************************************************/ 
package org.eclipse.rap.internal.design.example.managers;

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

import org.eclipse.jface.action.IContributionItem;
import org.eclipse.jface.internal.provisional.action.ToolBarManager2;
import org.eclipse.rwt.lifecycle.WidgetUtil;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.ToolBar;
import org.eclipse.swt.widgets.ToolItem;


public class ViewToolBarManager extends ToolBarManager2 {
  
  private static final String STYLING_VARIANT = "viewToolbar";
  private ToolBar toolBar;
  private ToolBar fakeToolbar;


  public ToolBar createControl(Composite parent) {
    if( !toolBarExist() && parent != null ) {
      toolBar = new ToolBar( parent, SWT.NONE );
      toolBar.setData( WidgetUtil.CUSTOM_VARIANT, STYLING_VARIANT );
      toolBar.setMenu( getContextMenuControl() );
      // create the fake Toolbar
      fakeToolbar = new ToolBar( parent, SWT.NONE );
      fakeToolbar.setVisible( false );
      update( true );
    }
    return toolBar;
  }
  
  public ToolBar getControl() {
    return toolBar;
  }
  
  private Menu getContextMenuControl() {
    Menu result = null;
    if( ( getContextMenuManager() != null ) && ( toolBar != null ) ) {
      Menu menuWidget = getContextMenuManager().getMenu();
      if( ( menuWidget == null ) || ( menuWidget.isDisposed() ) ) {
        menuWidget = getContextMenuManager().createContextMenu( toolBar);
      }
      result = menuWidget;
    }
    return result;
  }
  
  private boolean toolBarExist() {
    return toolBar != null && !toolBar.isDisposed();
  }
  
  /*
   * (non-Javadoc) Method declared on IContributionManager.
   */
  public void update( boolean force ) {
    if( isDirty() || force ) {
      if( toolBarExist() ) {

        // clean contains all active items without separators
        IContributionItem[] items = getItems();
        ArrayList clean = new ArrayList( items.length );
        for( int i = 0; i < items.length; ++i ) {
          IContributionItem ci = items[ i ];
          if( !ci.isSeparator() ) {
            clean.add( ci );
          }
        }
        // determine obsolete items (removed or non active)
        ToolItem[] mi = toolBar.getItems();
        ArrayList toRemove = new ArrayList();
        for( int i = 0; i < mi.length; i++ ) {
          toRemove.add( mi[ i ] );
        }
        // add fake toolbar items to the items to remove
        for( int i = 0; i < fakeToolbar.getItemCount(); i++ ) {
          toRemove.add( fakeToolbar.getItem( i ) );
        }

        // Turn redraw off if the number of items to be added
        // is above a certain threshold, to minimize flicker,
        // otherwise the toolbar can be seen to redraw after each item.
        // Do this before any modifications are made.
        // We assume each contribution item will contribute at least one
        // toolbar item.
        boolean useRedraw = clean.size() - ( mi.length - toRemove.size() ) >= 3;
        try {
          if( useRedraw ) {
            toolBar.setRedraw( false );
          }

          // remove obsolete items
          for( int i = toRemove.size(); --i >= 0; ) {
            ToolItem item = ( ToolItem ) toRemove.get(i);
            if( !item.isDisposed() ) {
              Control ctrl = item.getControl();
              if( ctrl != null ) {
                item.setControl( null );
                ctrl.dispose();
              }
              item.dispose();
            }
          }

          // add new items
          IContributionItem src, dest;
          mi = toolBar.getItems();
          int srcIx = 0;
          int destIx = 0;         
          
          for( Iterator e = clean.iterator(); e.hasNext(); ) {
            src = ( IContributionItem )e.next();

            // get corresponding item in SWT widget
            if( srcIx < mi.length ) {
              dest = ( IContributionItem ) mi[ srcIx ].getData();
            } else {
              dest = null;
            }

            if( dest != null && src.equals( dest ) ) {
              srcIx++;
              destIx++;
              continue;
            }

            if(    dest != null && dest.isSeparator()
                && src.isSeparator() ) 
            {
              mi[ srcIx ].setData( src );
              srcIx++;
              destIx++;
              continue;
            }

            // fill item if visible, if not fill it into the fake toolbar
            ToolBar tempToolBar = null;
            if( src.isVisible() ) {
              src.fill( toolBar, destIx );
              tempToolBar = toolBar;
            } else {
              src.fill( fakeToolbar, destIx );
              tempToolBar = fakeToolbar;
            }
            // check necessary for bug 306741
            if( destIx >= 0 && destIx < tempToolBar.getItemCount() - 1 ) {
              ToolItem toolItem = tempToolBar.getItem( destIx );
              toolItem.setData( src );
              toolItem.setData( WidgetUtil.CUSTOM_VARIANT, STYLING_VARIANT );
            }
          }

          // remove any old tool items not accounted for
          for( int i = mi.length; --i >= srcIx; ) {
            ToolItem item = mi[ i ];
            if( !item.isDisposed() ) {
              Control ctrl = item.getControl();
              if( ctrl != null ) {
                item.setControl( null );
                ctrl.dispose();
              }
              item.dispose();
            }
          }

          setDirty( false );
        } finally {
          // turn redraw back on if we turned it off above
          if( useRedraw ) {
            toolBar.setRedraw( true );
          }
        }
      }
    }
  }
  
  public List getToolItems() {
    List result = new ArrayList();
    for( int i = 0; i < toolBar.getItemCount(); i++ ) {
      result.add( toolBar.getItem( i ) );
    }
    for( int i = 0; i < fakeToolbar.getItemCount(); i++ ) {
      result.add( fakeToolbar.getItem( i ) );
    }
    return result;
  }

}