package org.glassbox.graphview;
   
   import org.glassbox.executor.Executor;
   
   import de.fzi.wim.guibase.graphview.graph.*;
   
   /***
      Not implemented yet.
    */
  public class OffScreenLayouter {
      private Executor _executor;
      private OffScreenLayoutStrategy _layout;
  
      /***
         Constructor.
         @param executor The executor to run the layout tasks.
         @param layout The layout strategy to be used.
       */
      public OffScreenLayouter(Executor executor, Graph onscreengraph, OffScreenLayoutStrategy layout) {
  	_executor = executor;
  	_layout = layout;
  	// _layout.getGraph().addGraphListener(new GraphHandler());
      }
  
      /***
         Do the layouting if necessary and notify the specified instance.
         @param notify The object to be notified when the layouting is finished.
       */
      public void doLayout(OffScreenLayoutNotify notify) {
  	// call shouldExecuteLayout() at strategy
  	// if layout is unchanged: 
  	//   if no layout task is running in the background: call notify.notifyLayoutUnchanged() 
  	//   else do nothing
  	// else
  	//   cancel running layout task if one is running
  	//   start new layout task
      }
  
      /***
      private class GraphHandler implements GraphListener {
      }
      */
  
      /***
      private class LayoutTask implements VisibleExecutor.VisibleTask, StatusBarExecutor.Task {
      }
      */
  }