// **********************************************************************
//
// <copyright>
//
// BBN Technologies
// 10 Moulton Street
// Cambridge, MA 02138
// (617) 873-8000
//
// Copyright (C) BBNT Solutions LLC. All rights reserved.
//
// </copyright>
// **********************************************************************
//
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/layer/policy/ListResetPCPolicy.java,v $
// $RCSfile: ListResetPCPolicy.java,v $
// $Revision: 1.6.2.2 $
// $Date: 2005/09/13 14:34:02 $
// $Author: dietrick $
//
// **********************************************************************
package com.bbn.openmap.layer.policy;
import com.bbn.openmap.layer.OMGraphicHandlerLayer;
import com.bbn.openmap.event.LayerStatusEvent;
import com.bbn.openmap.event.ProjectionEvent;
import com.bbn.openmap.omGraphics.OMGraphicList;
import com.bbn.openmap.proj.Projection;
import com.bbn.openmap.util.Debug;
/**
* ProjectionChangePolicy that uses a Layer SwingWorker to kick off a
* thread to call layer.prepare() and deletes the current
* OMGraphicList between projection changes. The standard behavior for
* layers that gather new OMGraphics for new projections.
*/
public class ListResetPCPolicy implements ProjectionChangePolicy {
/**
* Don't let this be null.
*/
protected OMGraphicHandlerLayer layer;
/**
* You MUST set a layer at some point.
*/
public ListResetPCPolicy() {}
/**
* Don't pass in a null layer.
*/
public ListResetPCPolicy(OMGraphicHandlerLayer layer) {
this.layer = layer;
}
public void setLayer(OMGraphicHandlerLayer l) {
layer = l;
}
public OMGraphicHandlerLayer getLayer() {
return layer;
}
public void projectionChanged(ProjectionEvent pe) {
if (layer != null) {
Projection proj = layer.setProjection(pe);
// proj will be null if the projection hasn't changed, a
// signal that work does not need to be done.
if (proj != null) {
if (Debug.debugging("layer")) {
Debug.output(getLayer().getName()
+ ": ListResetPCPolicy projectionChanged with NEW projection, resetting list.");
}
layer.setList(null);
// Check to see if the projection is worth reacting to.
if (layer.isProjectionOK(proj)) {
layer.doPrepare();
}
} else {
if (Debug.debugging("layer")) {
Debug.output(getLayer().getName()
+ ": ListResetPCPolicy projectionChanged with OLD projection, repainting.");
}
if (!layer.isWorking()) {
// This repaint may look redundant, but it handles
// the situation where a layer is removed from a
// map and readded when the projection doesn't
// change. Since it already had the projection,
// and remove() hasn't been called yet, the proj
// == null. When the new layer is added, it
// receives a projectionChanged call, and even
// though it's all set, it still needs to call
// repaint to have itself show up on the map.
layer.repaint();
layer.fireStatusUpdate(LayerStatusEvent.FINISH_WORKING);
}
}
} else {
Debug.error("ListResetPCPolicy.projectionChanged(): NULL layer, can't do anything.");
}
}
/**
* This is a subtle call, that dictates what should happen when
* the LayerWorker has completed working in it's thread. The
* LayerWorker.get() method returns whatever was returned in the
* OMGraphicHandler.prepare() method, an OMGraphicList. In most
* cases, this object should be set as the Layer's list at this
* time. Some Layers, working asynchronously with their data
* sources, might want nothing to happen and should use a policy
* that overrides this method so that nothing does.
*/
public void workerComplete(OMGraphicList aList) {
if (layer != null) {
layer.setList(aList);
}
}
}