/* A drop target for the ptolemy editor.
Copyright (c) 1999-2008 The Regents of the University of California.
All rights reserved.
Permission is hereby granted, without written agreement and without
license or royalty fees, to use, copy, modify, and distribute this
software and its documentation for any purpose, provided that the above
copyright notice and the following two paragraphs appear in all copies
of this software.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
ENHANCEMENTS, OR MODIFICATIONS.
PT_COPYRIGHT_VERSION_2
COPYRIGHTENDKEY
*/
package ptolemy.vergil.basic;
import java.awt.Color;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.List;
import java.util.Vector;
import javax.swing.JComponent;
import javax.swing.ToolTipManager;
import ptolemy.actor.gui.Configuration;
import ptolemy.kernel.util.Location;
import ptolemy.kernel.util.NamedObj;
import ptolemy.kernel.util.Singleton;
import ptolemy.kernel.util.StringAttribute;
import ptolemy.moml.MoMLChangeRequest;
import ptolemy.util.MessageHandler;
import ptolemy.vergil.kernel.AnimationRenderer;
import ptolemy.vergil.toolbox.PtolemyTransferable;
import ptolemy.vergil.toolbox.SnapConstraint;
import diva.canvas.CanvasComponent;
import diva.canvas.Figure;
import diva.canvas.FigureLayer;
import diva.graph.GraphController;
import diva.graph.GraphModel;
import diva.graph.GraphPane;
import diva.graph.JGraph;
import diva.util.UserObjectContainer;
//////////////////////////////////////////////////////////////////////////
//// EditorDropTarget
/**
This class provides drag-and-drop support. When this drop target
receives a transferable object containing a ptolemy entity, it creates
a new instance of the object, and adds it to the given graph.
If the drop location falls on top of an icon associated with an
instance of NamedObj, then the object is deposited inside that
instance (so the instance becomes its container). Otherwise,
the object is deposited inside the model associated with the
target graph. In either case, if the target container implements
the DropListener interface, then it is informed of the drop by
calling its dropped() method.
<p>
Sometimes, you will want to disable the feature that a drop
onto a NamedObj results in the dropped object being placed inside
that NamedObj. To disable this feature, call setDropIntoEnabled()
with a false argument.
@author Steve Neuendorffer and Edward A. Lee, Contributor: Michael Shilman
@version $Id: EditorDropTarget.java,v 1.57 2008/01/24 02:07:23 cxh Exp $
@since Ptolemy II 2.0
@Pt.ProposedRating Red (eal)
@Pt.AcceptedRating Red (johnr)
*/
public class EditorDropTarget extends DropTarget {
/** Construct a new graph target to operate on the given JGraph.
* @param graph The diva graph panel.
*/
public EditorDropTarget(JGraph graph) {
setComponent(graph);
try {
addDropTargetListener(new DTListener());
} catch (java.util.TooManyListenersException wow) {
}
}
///////////////////////////////////////////////////////////////////
//// public methods ////
/** Return true if the feature is enabled that a a drop onto an
* instance of NamedObj results in that NamedObj containing the
* dropped object. Otherwise, return false.
* @return True if drop into is enabled.
*/
public boolean isDropIntoEnabled() {
return _dropIntoEnabled;
}
/** Register additional DropTargetListeners.
* @param listener The DropTargetListener to be added.
*/
public void registerAdditionalListener(DropTargetListener listener) {
_additionalListeners.addElement(listener);
}
/** Remove an additional listener.
* @param listener The DropTargetListener to be removed.
*/
public void deRegisterAdditionalListener(DropTargetListener listener) {
_additionalListeners.remove(listener);
}
/** If the argument is false, then disable the feature that a
* a drop onto an instance of NamedObj results in that NamedObj
* containing the dropped object. If the argument is true, then
* reenable the feature. The feature is enabled by default.
* @param enabled False to disable the drop into feature.
*/
public void setDropIntoEnabled(boolean enabled) {
_dropIntoEnabled = enabled;
}
///////////////////////////////////////////////////////////////////
//// private variables ////
/** Flag indicating whether drop into is enabled. */
private boolean _dropIntoEnabled = true;
/** Vector to contain additional listeners. */
private Vector _additionalListeners = new Vector();
///////////////////////////////////////////////////////////////////
//// inner classes ////
/** The drop target listener used with the diva graph object.
*/
private class DTListener implements DropTargetListener {
///////////////////////////////////////////////////////////////
//// public methods ////
/** Accept the event if the data is a known key.
* This is called while a drag operation is ongoing,
* when the mouse pointer enters the operable part of
* the drop site for the DropTarget registered with
* this listener.
* @param dtde The drop event.
*/
public void dragEnter(DropTargetDragEvent dtde) {
//notify additionalListeners
for (int i = 0; i < _additionalListeners.size(); i++) {
DropTargetListener l = (DropTargetListener) _additionalListeners
.elementAt(i);
l.dragEnter(dtde);
}
if (dtde.isDataFlavorSupported(PtolemyTransferable.namedObjFlavor)) {
dtde.acceptDrag(DnDConstants.ACTION_COPY_OR_MOVE);
} else {
dtde.rejectDrag();
}
}
/** Remove any highlighting that might be active.
* This is called while a drag operation is ongoing, when the mouse
* pointer has exited the operable part of the drop site for the
* DropTarget registered with this listener.
* @param dtde The drop event.
*/
public void dragExit(DropTargetEvent dtde) {
//notify additionalListeners
for (int i = 0; i < _additionalListeners.size(); i++) {
DropTargetListener l = (DropTargetListener) _additionalListeners
.elementAt(i);
l.dragExit(dtde);
}
if (_highlighted != null) {
_highlighter.renderDeselected(_highlightedFigure);
_highlighted = null;
_highlightedFigure = null;
}
}
/** If the location of the event is over an icon for
* an instance of NamedObj, then highlight that icon.
* This is called when a drag operation is ongoing,
* while the mouse pointer is still over the operable
* part of the drop site for the DropTarget registered
* with this listener.
* @param dtde The drop event.
*/
public void dragOver(DropTargetDragEvent dtde) {
//notify additionalListeners
for (int i = 0; i < _additionalListeners.size(); i++) {
DropTargetListener l = (DropTargetListener) _additionalListeners
.elementAt(i);
l.dragOver(dtde);
}
// See whether there is a container under the point.
Point2D originalPoint = SnapConstraint.constrainPoint(dtde
.getLocation());
NamedObj over = _getObjectUnder(originalPoint);
if (over != _highlighted) {
if (_highlighted != null) {
_highlighter.renderDeselected(_highlightedFigure);
_highlighted = null;
_highlightedFigure = null;
}
if ((over != null) && _dropIntoEnabled) {
if (_highlighter == null) {
_highlighter = new AnimationRenderer(Color.white);
}
_highlighted = over;
_highlightedFigure = _getFigureUnder(originalPoint);
_highlighter.renderSelected(_highlightedFigure);
}
}
// Used to do this... Any reason for it?
// dragEnter(dtde);
}
/** If the transferrable object is recognized as a Ptolemy II object,
* then use the MoML description of the object to create a new
* instance of the object at the drop location. If the drop
* location is on top of an icon representing an instance of
* NamedObj, then make that instance the container of the new
* object. Otherwise, make the model associated with the graph
* the container.
* This is called when the drag operation has terminated with a
* drop on the operable part of the drop site for the DropTarget
* registered with this listener.
* @param dtde The drop event.
*/
public void drop(DropTargetDropEvent dtde) {
//notify additionalListeners
for (int i = 0; i < _additionalListeners.size(); i++) {
DropTargetListener l = (DropTargetListener) _additionalListeners
.elementAt(i);
l.drop(dtde);
}
// Unhighlight the target. Do this first in case
// errors occur... Don't want to leave highlighting.
if (_highlighted != null) {
_highlighter.renderDeselected(_highlightedFigure);
_highlighted = null;
_highlightedFigure = null;
}
// See whether there is a container under the point.
Point2D originalPoint = SnapConstraint.constrainPoint(dtde
.getLocation());
NamedObj container = _getObjectUnder(originalPoint);
GraphPane pane = ((JGraph) getComponent()).getGraphPane();
if ((container == null) || !_dropIntoEnabled) {
// Find the default container for the dropped object
GraphController controller = pane.getGraphController();
GraphModel model = controller.getGraphModel();
container = (NamedObj) model.getRoot();
}
// Find the location for the dropped objects.
// Account for the scaling in the pane.
Point2D transformedPoint = new Point2D.Double();
pane.getTransformContext().getInverseTransform().transform(
originalPoint, transformedPoint);
// Get an iterator over objects to drop.
Iterator iterator = null;
if (dtde.isDataFlavorSupported(PtolemyTransferable.namedObjFlavor)) {
try {
dtde.acceptDrop(DnDConstants.ACTION_COPY_OR_MOVE);
iterator = (Iterator) dtde
.getTransferable()
.getTransferData(PtolemyTransferable.namedObjFlavor);
} catch (Exception e) {
MessageHandler.error(
"Can't find a supported data flavor for drop in "
+ dtde, e);
return;
}
} else {
dtde.rejectDrop();
}
if (iterator == null) {
// Nothing to drop!
return;
}
// Create the MoML change request to instantiate the new objects.
StringBuffer moml = new StringBuffer();
moml.append("<group>");
while (iterator.hasNext()) {
final NamedObj dropObj = (NamedObj) iterator.next();
final String name;
if (dropObj instanceof Singleton) {
name = dropObj.getName();
} else {
name = container.uniqueName(dropObj.getName());
}
// Constrain point to snap to grid.
Point2D newPoint = SnapConstraint
.constrainPoint(transformedPoint);
/* At this point we wish to provide for an alternatice way to get the MOML
* code for the drop object. This is to allow for a drop object that may just
* contain a reference (e.g. an LSID) to the complete MOML rather than including
* all the information in the tree node object being dragged.
* DFH July 2007
*/
// first try to get the LSID; if one cannot be found use the Ptolemy method for dropping
boolean lsidFlag = true;
try {
String lsidString = ((StringAttribute) (dropObj
.getAttribute("entityId"))).getExpression();
if ((lsidString == null) || (lsidString.equals("")))
lsidFlag = false;
} catch (Exception eee) {
lsidFlag = false;
}
String result = "";
String rootNodeName = dropObj.getElementName();
List configsList = Configuration.configurations();
Configuration config = null;
Object object = null;
for (Iterator it = configsList.iterator(); it.hasNext();) {
config = (Configuration) it.next();
if (config != null)
break;
}
StringAttribute alternateGetMomlActionAttribute = (StringAttribute) config
.getAttribute("_alternateGetMomlAction");
if ((alternateGetMomlActionAttribute != null) && (lsidFlag)) {
String alternateGetMomlClassName = alternateGetMomlActionAttribute
.getExpression();
try {
Class getMomlClass = Class
.forName(alternateGetMomlClassName);
object = getMomlClass.newInstance();
Class[] parameterTypes = new Class[] { NamedObj.class };
Method getMomlMethod;
getMomlMethod = getMomlClass.getMethod("getMoml",
parameterTypes);
Object[] arguments = new Object[] { dropObj };
result = (String) getMomlMethod.invoke(object,
arguments);
int int1 = 1;
int int2 = result.indexOf(" ");
rootNodeName = result.substring(int1, int2);
// following string substitution is needed to replace possible name changes
// when multiple copies of an actor are added to a workspace canvas
// (name then has integer appended to it) -- DFH
int1 = result.indexOf("\"", 1);
int2 = result.indexOf("\"", int1 + 1);
result = result.substring(0, int1 + 1) + name
+ result.substring(int2, result.length());
// System.out.println("alternate getMOML result string (in EditorDropTarget) - "+result);
} catch (Exception w) {
System.out.println("Error creating alternateGetMoml!");
}
} else { // default method for PtolemyII use
result = dropObj.exportMoML(name);
}
moml.append(result);
moml.append("<" + rootNodeName + " name=\"" + name + "\">\n");
moml
.append("<property name=\"_location\" class=\"ptolemy.kernel.util.Location\" value=\"{");
moml.append((int) newPoint.getX());
moml.append(", ");
moml.append((int) newPoint.getY());
moml.append("}\"/>\n</" + rootNodeName + ">\n");
}
moml.append("</group>");
MoMLChangeRequest request = new MoMLChangeRequest(this, container,
moml.toString());
request.setUndoable(true);
container.requestChange(request);
dtde.dropComplete(true); //success!
//Added by MB 6Apr06 - without this, tooltips don't work
//after first actor is dragged to canvas from library, until
//pane loses & regains focus
JComponent comp = (JComponent) getComponent();
if (comp != null) {
ToolTipManager.sharedInstance().registerComponent(comp);
}
}
/** Accept the event if the data is a known key.
* This is called if the user has modified the current drop gesture.
* @param dtde The drop event.
*/
public void dropActionChanged(DropTargetDragEvent dtde) {
//notify additionalListeners
for (int i = 0; i < _additionalListeners.size(); i++) {
DropTargetListener l = (DropTargetListener) _additionalListeners
.elementAt(i);
l.dropActionChanged(dtde);
}
// Used to do this... Not needed?
// dragEnter(dtde);
}
///////////////////////////////////////////////////////////////
//// private methods ////
/** Return the figure that is an icon of a NamedObj and is
* under the specified point, or null if there is none.
* @param point The point in the graph pane.
* @return The object under the specified point, or null if there
* is none or it is not a NamedObj.
*/
private Figure _getFigureUnder(Point2D point) {
GraphPane pane = ((JGraph) getComponent()).getGraphPane();
// Account for the scaling in the pane.
Point2D transformedPoint = new Point2D.Double();
pane.getTransformContext().getInverseTransform().transform(point,
transformedPoint);
FigureLayer layer = pane.getForegroundLayer();
// Find the figure under the point.
// NOTE: Unfortunately, FigureLayer.getCurrentFigure() doesn't
// work with a drop target (I guess it hasn't seen the mouse events),
// so we have to use a lower level mechanism.
double halo = layer.getPickHalo();
double width = halo * 2;
Rectangle2D region = new Rectangle2D.Double(transformedPoint.getX()
- halo, transformedPoint.getY() - halo, width, width);
CanvasComponent figureUnderMouse = layer.pick(region);
// Find a user object belonging to the figure under the mouse
// or to any figure containing it (it may be a composite figure).
Object objectUnderMouse = null;
while (figureUnderMouse instanceof UserObjectContainer
&& (objectUnderMouse == null)) {
objectUnderMouse = ((UserObjectContainer) figureUnderMouse)
.getUserObject();
if (objectUnderMouse instanceof NamedObj) {
if (figureUnderMouse instanceof Figure) {
return (Figure) figureUnderMouse;
}
}
figureUnderMouse = figureUnderMouse.getParent();
}
return null;
}
/** Return the object under the specified point, or null if there
* is none.
* @param point The point in the graph pane.
* @return The object under the specified point, or null if there
* is none or it is not a NamedObj.
*/
private NamedObj _getObjectUnder(Point2D point) {
Figure figureUnderMouse = _getFigureUnder(point);
if (figureUnderMouse == null) {
return null;
}
Object objectUnderMouse = ((UserObjectContainer) figureUnderMouse)
.getUserObject();
// Object might be a Location, in which case we want its container.
if (objectUnderMouse instanceof Location) {
return ((NamedObj) objectUnderMouse).getContainer();
} else if (objectUnderMouse instanceof NamedObj) {
return (NamedObj) objectUnderMouse;
}
return null;
}
///////////////////////////////////////////////////////////////
//// private variables ////
// Currently highlighted drop target.
private NamedObj _highlighted = null;
// Currently highlighted figure.
private Figure _highlightedFigure = null;
// The renderer used for highlighting.
private AnimationRenderer _highlighter = null;
}
}