Code
class TabTransferHandler extends TransferHandler {
private final DataFlavor localObjectFlavor;
public TabTransferHandler() {
System.out.println("TabTransferHandler");
localObjectFlavor = new DataFlavor(DnDTabData.class, "DnDTabData");
}
private DnDTabbedPane source = null;
@Override protected Transferable createTransferable(JComponent c) {
System.out.println("createTransferable");
if (c instanceof DnDTabbedPane) source = (DnDTabbedPane) c;
return new Transferable() {
@Override public DataFlavor[] getTransferDataFlavors() {
return new DataFlavor[] {localObjectFlavor};
}
@Override public boolean isDataFlavorSupported(DataFlavor flavor) {
return Objects.equals(localObjectFlavor, flavor);
}
@Override public Object getTransferData(DataFlavor flavor)
throws UnsupportedFlavorException, IOException {
if (isDataFlavorSupported(flavor)) {
return new DnDTabData(source);
} else {
throw new UnsupportedFlavorException(flavor);
}
}
};
}
@Override public boolean canImport(TransferSupport support) {
//System.out.println("canImport");
if (!support.isDrop() || !support.isDataFlavorSupported(localObjectFlavor)) {
return false;
}
support.setDropAction(TransferHandler.MOVE);
DropLocation tdl = support.getDropLocation();
Point pt = tdl.getDropPoint();
DnDTabbedPane target = (DnDTabbedPane) support.getComponent();
target.autoScrollTest(pt);
DnDTabbedPane.DropLocation dl =
(DnDTabbedPane.DropLocation) target.dropLocationForPoint(pt);
int idx = dl.getIndex();
boolean isDroppable = false;
if (target == source) {
isDroppable = target.getTabAreaBounds().contains(pt) && idx >= 0 &&
idx != target.dragTabIndex && idx != target.dragTabIndex + 1;
} else {
if (source != null && target != source.getComponentAt(source.dragTabIndex)) {
isDroppable = target.getTabAreaBounds().contains(pt) && idx >= 0;
}
}
Component c = target.getRootPane().getGlassPane();
c.setCursor(isDroppable?DragSource.DefaultMoveDrop:DragSource.DefaultMoveNoDrop);
if (isDroppable) {
support.setShowDropLocation(true);
dl.setDroppable(true);
target.setDropLocation(dl, null, true);
return true;
} else {
support.setShowDropLocation(false);
dl.setDroppable(false);
target.setDropLocation(dl, null, false);
return false;
}
}
private BufferedImage makeDragTabImage(DnDTabbedPane tabbedPane) {
Rectangle rect = tabbedPane.getBoundsAt(tabbedPane.dragTabIndex);
BufferedImage image = new BufferedImage(
tabbedPane.getWidth(), tabbedPane.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics g = image.getGraphics();
tabbedPane.paint(g);
g.dispose();
if (rect.x < 0) {
rect.translate(-rect.x, 0);
}
if (rect.y < 0) {
rect.translate(0, -rect.y);
}
if (rect.x + rect.width > image.getWidth()) {
rect.width = image.getWidth() - rect.x;
}
if (rect.y + rect.height > image.getHeight()) {
rect.height = image.getHeight() - rect.y;
}
return image.getSubimage(rect.x, rect.y, rect.width, rect.height);
}
private static GhostGlassPane glassPane;
@Override public int getSourceActions(JComponent c) {
System.out.println("getSourceActions");
DnDTabbedPane src = (DnDTabbedPane) c;
if (glassPane == null) {
c.getRootPane().setGlassPane(glassPane = new GhostGlassPane(src));
}
if (src.dragTabIndex < 0) return TransferHandler.NONE;
glassPane.setImage(makeDragTabImage(src));
source = src;
//setDragImage(img); //java 1.7.0-ea-b84
glassPane.setVisible(true);
return TransferHandler.MOVE;
}
@Override public boolean importData(TransferSupport support) {
System.out.println("importData");
if (!canImport(support)) return false;
DnDTabbedPane target = (DnDTabbedPane) support.getComponent();
DnDTabbedPane.DropLocation dl = target.getDropLocation();
try {
DnDTabbedPane source = (DnDTabbedPane) support.getTransferable()
.getTransferData(localObjectFlavor);
int index = dl.getIndex(); //boolean insert = dl.isInsert();
if (target == source) {
source.convertTab(source.dragTabIndex, index);
} else {
source.exportTab(source.dragTabIndex, target, index);
}
return true;
} catch (UnsupportedFlavorException ufe) {
ufe.printStackTrace();
} catch (IOException ioe) {
ioe.printStackTrace();
}
return false;
}
@Override protected void exportDone(JComponent c, Transferable data, int action) {
System.out.println("exportDone");
DnDTabbedPane src = (DnDTabbedPane) c;
c.getRootPane().getGlassPane().setVisible(false);
src.setDropLocation(null, null, false);
}
}
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