I'm trying to create a connection between two ellipses on a canvas, AFTER having created the ellipses and storing their positions on the canvas. These stored positions need to be used to create the connection. The code I've written works for RectangleFigures but does not for Ellipses. I can't seem to see the difference between the two cases. Could someone please help? Thanks.*I've added short testable code to illustrate my problem. To see it working with Rectangles, please uncomment the line saying UNCOMMENT THIS
import java.util.ArrayList;
import org.eclipse.draw2d.ColorConstants;
import org.eclipse.draw2d.ChopboxAnchor;
import org.eclipse.draw2d.Ellipse;
import org.eclipse.draw2d.Figure;
import org.eclipse.draw2d.IFigure;
import org.eclipse.draw2d.LightweightSystem;
import org.eclipse.draw2d.PolygonDecoration;
import org.eclipse.draw2d.PolylineConnection;
import org.eclipse.draw2d.RectangleFigure;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.draw2d.geometry.Rectangle;
import org.eclipse.swt.SWT;
import org.eclipse.swt.dnd.DND;
import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DragSourceEvent;
import org.eclipse.swt.dnd.DragSourceListener;
import org.eclipse.swt.dnd.DropTarget;
import org.eclipse.swt.dnd.DropTargetEvent;
import org.eclipse.swt.dnd.DropTargetListener;
import org.eclipse.swt.dnd.TextTransfer;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Layout;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Label;
public class EllipseProblem
{
private Shell shell;
private Display display;
private final Label lblUnicorn;
private final Canvas canvas;
final IFigure panel;
public static ArrayList canvasElements= new ArrayList();
public static void main(String args[])
{
new EllipseProblem();
}
public EllipseProblem()
{
display = new Display();
shell = new Shell(display);
shell.setText("SWT Application");
shell.setLayout(new GridLayout(2, false));
Group grpPalette = new Group(shell, SWT.NONE);
grpPalette.setText("Palette");
grpPalette.setLayout(new GridLayout());
grpPalette.setLayoutData(new GridData(SWT.BEGINNING, SWT.FILL, false, true));
lblUnicorn = new Label(grpPalette, SWT.BORDER | SWT.HORIZONTAL | SWT.CENTER);
lblUnicorn.setText("UNICORN");
lblUnicorn.setAlignment(SWT.CENTER);
final Group grpCanvas = new Group(shell, SWT.NONE);
grpCanvas.setText("Canvas");
grpCanvas.setLayout(new GridLayout());
grpCanvas.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
canvas = new Canvas(grpCanvas, SWT.NONE);
canvas.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
Button btnCreate = new Button(grpPalette, SWT.CENTER);
GridData gd_btnCreate = new GridData(SWT.LEFT, SWT.CENTER, false, false, 1, 1);
gd_btnCreate.widthHint = 87;
gd_btnCreate.heightHint = 33;
btnCreate.setLayoutData(gd_btnCreate);
btnCreate.addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
drawConnection();
}
});
btnCreate.setText("Make Connection");
LightweightSystem lws = new LightweightSystem(canvas);
panel = new Figure();
lws.setContents(panel);
DragSource dragSource1 = new DragSource(lblUnicorn, DND.DROP_COPY);
Transfer[] transfers1 = new Transfer[] { TextTransfer.getInstance() };
dragSource1.setTransfer(transfers1);
dragSource1.addDragListener(new DragSourceListener()
{
public void dragStart(DragSourceEvent event)
{
if (lblUnicorn.getText().length() == 0)
{
event.doit = false;
}
}
public void dragSetData(DragSourceEvent event)
{
if (TextTransfer.getInstance().isSupportedType(event.dataType))
{
event.data = lblUnicorn.getText();
}
}
public void dragFinished(DragSourceEvent event)
{
}
});
Transfer[] types = new Transfer[] { TextTransfer.getInstance() };
DropTarget dropTarget = new DropTarget(canvas, DND.DROP_COPY | DND.DROP_DEFAULT);
dropTarget.setTransfer(types);
dropTarget.addDropListener(new DropTargetListener()
{
public void dragEnter(DropTargetEvent event)
{
if (event.detail == DND.DROP_DEFAULT)
{
if ((event.operations & DND.DROP_COPY) != 0)
{
event.detail = DND.DROP_COPY;
}
else
{
event.detail = DND.DROP_NONE;
}
}
}
public void dragLeave(DropTargetEvent event)
{
}
public void dragOperationChanged(DropTargetEvent event)
{
}
public void dragOver(DropTargetEvent event)
{
}
public void drop(DropTargetEvent event)
{
}
public void dropAccept(final DropTargetEvent event)
{
if (TextTransfer.getInstance().isSupportedType(event.currentDataType))
{
String d = (String) TextTransfer.getInstance().nativeToJava(event.currentDataType);
final String finald= d;
org.eclipse.swt.graphics.Point droppoint = canvas.toControl(event.x, event.y);
canvasElements.add(droppoint);
Rectangle rect=new Rectangle(droppoint.x, droppoint.y, 40, 20);
Rectangle rect2=new Rectangle(droppoint.x+20, droppoint.y, 100, 25);
Ellipse node= new Ellipse();
//RectangleFigure node= new RectangleFigure(); UNCOMMENT THIS
node.setBounds(rect);
System.out.println(node.getBounds());
node.setLocation(new Point(droppoint.x, droppoint.y));
node.setBackgroundColor(ColorConstants.red);
panel.add(node);
org.eclipse.draw2d.Label droppedName=
new org.eclipse.draw2d.Label(finald);
droppedName.setLocation(new Point(droppoint.x, droppoint.y)); //draw2d. point
droppedName.setBounds(rect2);
panel.add(node);
panel.add(droppedName);
canvas.redraw();
}
}
});
shell.pack();
shell.setSize(400, 300);
shell.open();
while (!shell.isDisposed())
{
if (!display.readAndDispatch())
{
display.sleep();
}
}
}
protected void drawConnection()
{
org.eclipse.swt.graphics.Point swt_origin= (org.eclipse.swt.graphics.Point) canvasElements.get(0);
org.eclipse.draw2d.geometry.Point origin_point= new org.eclipse.draw2d.geometry.Point(swt_origin.x, swt_origin.y);
org.eclipse.swt.graphics.Point swt_destination= (org.eclipse.swt.graphics.Point) canvasElements.get(1);
org.eclipse.draw2d.geometry.Point destination_point= new org.eclipse.draw2d.geometry.Point(swt_destination.x, swt_destination.y);
IFigure origin = panel.findFigureAt(origin_point);
IFigure destination = panel.findFigureAt(destination_point);
PolylineConnection conn = new PolylineConnection();
conn.setSourceAnchor(new ChopboxAnchor(origin));
conn.setTargetAnchor(new ChopboxAnchor(destination));
conn.setTargetDecoration(new PolygonDecoration());
panel.add(conn);
}
}
