0N/A/*
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2362N/A * published by the Free Software Foundation. Oracle designates this
0N/A * particular file as subject to the "Classpath" exception as provided
2362N/A * by Oracle in the LICENSE file that accompanied this code.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
0N/A *
2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
2362N/A * or visit www.oracle.com if you need additional information or have any
2362N/A * questions.
0N/A */
0N/Apackage javax.swing.plaf.basic;
0N/A
0N/Aimport java.awt.Toolkit;
0N/Aimport java.awt.event.*;
0N/Aimport java.awt.dnd.DragSource;
0N/Aimport javax.swing.*;
0N/Aimport sun.awt.dnd.SunDragSourceContextPeer;
0N/Aimport sun.awt.AppContext;
0N/A
0N/A/**
0N/A * Drag gesture recognition support for classes that have a
0N/A * <code>TransferHandler</code>. The gesture for a drag in this class is a mouse
0N/A * press followed by movement by <code>DragSource.getDragThreshold()</code>
0N/A * pixels. An instance of this class is maintained per AppContext, and the
0N/A * public static methods call into the appropriate instance.
0N/A *
0N/A * @author Shannon Hickey
0N/A */
0N/Aclass DragRecognitionSupport {
0N/A private int motionThreshold;
0N/A private MouseEvent dndArmedEvent;
0N/A private JComponent component;
0N/A
0N/A /**
0N/A * This interface allows us to pass in a handler to mouseDragged,
0N/A * so that we can be notified immediately before a drag begins.
0N/A */
0N/A public static interface BeforeDrag {
0N/A public void dragStarting(MouseEvent me);
0N/A }
0N/A
0N/A /**
0N/A * Returns the DragRecognitionSupport for the caller's AppContext.
0N/A */
0N/A private static DragRecognitionSupport getDragRecognitionSupport() {
0N/A DragRecognitionSupport support =
0N/A (DragRecognitionSupport)AppContext.getAppContext().
0N/A get(DragRecognitionSupport.class);
0N/A
0N/A if (support == null) {
0N/A support = new DragRecognitionSupport();
0N/A AppContext.getAppContext().put(DragRecognitionSupport.class, support);
0N/A }
0N/A
0N/A return support;
0N/A }
0N/A
0N/A /**
0N/A * Returns whether or not the event is potentially part of a drag sequence.
0N/A */
0N/A public static boolean mousePressed(MouseEvent me) {
614N/A return getDragRecognitionSupport().mousePressedImpl(me);
0N/A }
0N/A
0N/A /**
0N/A * If a dnd recognition has been going on, return the MouseEvent
0N/A * that started the recognition. Otherwise, return null.
0N/A */
0N/A public static MouseEvent mouseReleased(MouseEvent me) {
614N/A return getDragRecognitionSupport().mouseReleasedImpl(me);
0N/A }
0N/A
0N/A /**
0N/A * Returns whether or not a drag gesture recognition is ongoing.
0N/A */
0N/A public static boolean mouseDragged(MouseEvent me, BeforeDrag bd) {
614N/A return getDragRecognitionSupport().mouseDraggedImpl(me, bd);
0N/A }
0N/A
0N/A private void clearState() {
0N/A dndArmedEvent = null;
0N/A component = null;
0N/A }
0N/A
0N/A private int mapDragOperationFromModifiers(MouseEvent me,
0N/A TransferHandler th) {
0N/A
0N/A if (th == null || !SwingUtilities.isLeftMouseButton(me)) {
0N/A return TransferHandler.NONE;
0N/A }
0N/A
0N/A return SunDragSourceContextPeer.
0N/A convertModifiersToDropAction(me.getModifiersEx(),
0N/A th.getSourceActions(component));
0N/A }
0N/A
0N/A /**
0N/A * Returns whether or not the event is potentially part of a drag sequence.
0N/A */
0N/A private boolean mousePressedImpl(MouseEvent me) {
0N/A component = (JComponent)me.getSource();
0N/A
0N/A if (mapDragOperationFromModifiers(me, component.getTransferHandler())
0N/A != TransferHandler.NONE) {
0N/A
0N/A motionThreshold = DragSource.getDragThreshold();
0N/A dndArmedEvent = me;
0N/A return true;
0N/A }
0N/A
0N/A clearState();
0N/A return false;
0N/A }
0N/A
0N/A /**
0N/A * If a dnd recognition has been going on, return the MouseEvent
0N/A * that started the recognition. Otherwise, return null.
0N/A */
0N/A private MouseEvent mouseReleasedImpl(MouseEvent me) {
0N/A /* no recognition has been going on */
0N/A if (dndArmedEvent == null) {
0N/A return null;
0N/A }
0N/A
0N/A MouseEvent retEvent = null;
0N/A
0N/A if (me.getSource() == component) {
0N/A retEvent = dndArmedEvent;
0N/A } // else component has changed unexpectedly, so return null
0N/A
0N/A clearState();
0N/A return retEvent;
0N/A }
0N/A
0N/A /**
0N/A * Returns whether or not a drag gesture recognition is ongoing.
0N/A */
0N/A private boolean mouseDraggedImpl(MouseEvent me, BeforeDrag bd) {
0N/A /* no recognition is in progress */
0N/A if (dndArmedEvent == null) {
0N/A return false;
0N/A }
0N/A
0N/A /* component has changed unexpectedly, so bail */
0N/A if (me.getSource() != component) {
0N/A clearState();
0N/A return false;
0N/A }
0N/A
0N/A int dx = Math.abs(me.getX() - dndArmedEvent.getX());
0N/A int dy = Math.abs(me.getY() - dndArmedEvent.getY());
0N/A if ((dx > motionThreshold) || (dy > motionThreshold)) {
0N/A TransferHandler th = component.getTransferHandler();
0N/A int action = mapDragOperationFromModifiers(me, th);
0N/A if (action != TransferHandler.NONE) {
0N/A /* notify the BeforeDrag instance */
0N/A if (bd != null) {
0N/A bd.dragStarting(dndArmedEvent);
0N/A }
0N/A th.exportAsDrag(component, dndArmedEvent, action);
0N/A clearState();
0N/A }
0N/A }
0N/A
0N/A return true;
0N/A }
0N/A}