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Diffstat (limited to 'bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/carbon/org/eclipse/swt/dnd/DragSource.java')
| -rw-r--r-- | bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/carbon/org/eclipse/swt/dnd/DragSource.java | 567 |
1 files changed, 567 insertions, 0 deletions
diff --git a/bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/carbon/org/eclipse/swt/dnd/DragSource.java b/bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/carbon/org/eclipse/swt/dnd/DragSource.java new file mode 100644 index 0000000000..414c209721 --- /dev/null +++ b/bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/carbon/org/eclipse/swt/dnd/DragSource.java @@ -0,0 +1,567 @@ +/******************************************************************************* + * Copyright (c) 2000, 2009 IBM Corporation and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * which accompanies this distribution, and is available at + * http://www.eclipse.org/legal/epl-v10.html + * + * Contributors: + * IBM Corporation - initial API and implementation + *******************************************************************************/ +package org.eclipse.swt.dnd; + + +import org.eclipse.swt.*; +import org.eclipse.swt.graphics.*; +import org.eclipse.swt.widgets.*; +import org.eclipse.swt.internal.Callback; +import org.eclipse.swt.internal.carbon.CGPoint; +import org.eclipse.swt.internal.carbon.EventRecord; +import org.eclipse.swt.internal.carbon.OS; +import org.eclipse.swt.internal.carbon.Point; + +/** + * + * <code>DragSource</code> defines the source object for a drag and drop transfer. + * + * <p>IMPORTANT: This class is <em>not</em> intended to be subclassed.</p> + * + * <p>A drag source is the object which originates a drag and drop operation. For the specified widget, + * it defines the type of data that is available for dragging and the set of operations that can + * be performed on that data. The operations can be any bit-wise combination of DND.MOVE, DND.COPY or + * DND.LINK. The type of data that can be transferred is specified by subclasses of Transfer such as + * TextTransfer or FileTransfer. The type of data transferred can be a predefined system type or it + * can be a type defined by the application. For instructions on how to define your own transfer type, + * refer to <code>ByteArrayTransfer</code>.</p> + * + * <p>You may have several DragSources in an application but you can only have one DragSource + * per Control. Data dragged from this DragSource can be dropped on a site within this application + * or it can be dropped on another application such as an external Text editor.</p> + * + * <p>The application supplies the content of the data being transferred by implementing the + * <code>DragSourceListener</code> and associating it with the DragSource via DragSource#addDragListener.</p> + * + * <p>When a successful move operation occurs, the application is required to take the appropriate + * action to remove the data from its display and remove any associated operating system resources or + * internal references. Typically in a move operation, the drop target makes a copy of the data + * and the drag source deletes the original. However, sometimes copying the data can take a long + * time (such as copying a large file). Therefore, on some platforms, the drop target may actually + * move the data in the operating system rather than make a copy. This is usually only done in + * file transfers. In this case, the drag source is informed in the DragEnd event that a + * DROP_TARGET_MOVE was performed. It is the responsibility of the drag source at this point to clean + * up its displayed information. No action needs to be taken on the operating system resources.</p> + * + * <p> The following example shows a Label widget that allows text to be dragged from it.</p> + * + * <code><pre> + * // Enable a label as a Drag Source + * Label label = new Label(shell, SWT.NONE); + * // This example will allow text to be dragged + * Transfer[] types = new Transfer[] {TextTransfer.getInstance()}; + * // This example will allow the text to be copied or moved to the drop target + * int operations = DND.DROP_MOVE | DND.DROP_COPY; + * + * DragSource source = new DragSource(label, operations); + * source.setTransfer(types); + * source.addDragListener(new DragSourceListener() { + * public void dragStart(DragSourceEvent e) { + * // Only start the drag if there is actually text in the + * // label - this text will be what is dropped on the target. + * if (label.getText().length() == 0) { + * event.doit = false; + * } + * }; + * public void dragSetData(DragSourceEvent event) { + * // A drop has been performed, so provide the data of the + * // requested type. + * // (Checking the type of the requested data is only + * // necessary if the drag source supports more than + * // one data type but is shown here as an example). + * if (TextTransfer.getInstance().isSupportedType(event.dataType)){ + * event.data = label.getText(); + * } + * } + * public void dragFinished(DragSourceEvent event) { + * // A Move operation has been performed so remove the data + * // from the source + * if (event.detail == DND.DROP_MOVE) + * label.setText(""); + * } + * }); + * </pre></code> + * + * + * <dl> + * <dt><b>Styles</b></dt> <dd>DND.DROP_NONE, DND.DROP_COPY, DND.DROP_MOVE, DND.DROP_LINK</dd> + * <dt><b>Events</b></dt> <dd>DND.DragStart, DND.DragSetData, DND.DragEnd</dd> + * </dl> + * + * @see <a href="http://www.eclipse.org/swt/snippets/#dnd">Drag and Drop snippets</a> + * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: DNDExample</a> + * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> + * @noextend This class is not intended to be subclassed by clients. + */ +public class DragSource extends Widget { + + // info for registering as a drag source + Control control; + Listener controlListener; + Transfer[] transferAgents = new Transfer[0]; + DragSourceEffect dragEffect; + + static final String DEFAULT_DRAG_SOURCE_EFFECT = "DEFAULT_DRAG_SOURCE_EFFECT"; //$NON-NLS-1$ + static Callback DragSendDataProc; + + static { + DragSendDataProc = new Callback(DragSource.class, "DragSendDataProc", 4); //$NON-NLS-1$ + int dragSendDataProcAddress = DragSendDataProc.getAddress(); + if (dragSendDataProcAddress == 0) SWT.error(SWT.ERROR_NO_MORE_CALLBACKS); + } + +/** + * Creates a new <code>DragSource</code> to handle dragging from the specified <code>Control</code>. + * Creating an instance of a DragSource may cause system resources to be allocated depending on the platform. + * It is therefore mandatory that the DragSource instance be disposed when no longer required. + * + * @param control the <code>Control</code> that the user clicks on to initiate the drag + * @param style the bitwise OR'ing of allowed operations; this may be a combination of any of + * DND.DROP_NONE, DND.DROP_COPY, DND.DROP_MOVE, DND.DROP_LINK + * + * @exception SWTException <ul> + * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> + * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> + * </ul> + * @exception SWTError <ul> + * <li>ERROR_CANNOT_INIT_DRAG - unable to initiate drag source; this will occur if more than one + * drag source is created for a control or if the operating system will not allow the creation + * of the drag source</li> + * </ul> + * + * <p>NOTE: ERROR_CANNOT_INIT_DRAG should be an SWTException, since it is a + * recoverable error, but can not be changed due to backward compatibility.</p> + * + * @see Widget#dispose + * @see DragSource#checkSubclass + * @see DND#DROP_NONE + * @see DND#DROP_COPY + * @see DND#DROP_MOVE + * @see DND#DROP_LINK + */ +public DragSource(Control control, int style) { + super (control, checkStyle(style)); + this.control = control; + if (control.getData(DND.DRAG_SOURCE_KEY) != null) { + DND.error(DND.ERROR_CANNOT_INIT_DRAG); + } + control.setData(DND.DRAG_SOURCE_KEY, this); + + controlListener = new Listener () { + public void handleEvent (Event event) { + if (event.type == SWT.Dispose) { + if (!DragSource.this.isDisposed()) { + DragSource.this.dispose(); + } + } + if (event.type == SWT.DragDetect) { + if (!DragSource.this.isDisposed()) { + DragSource.this.drag(event); + } + } + } + }; + control.addListener (SWT.Dispose, controlListener); + control.addListener (SWT.DragDetect, controlListener); + + this.addListener(SWT.Dispose, new Listener() { + public void handleEvent(Event e) { + onDispose(); + } + }); + + Object effect = control.getData(DEFAULT_DRAG_SOURCE_EFFECT); + if (effect instanceof DragSourceEffect) { + dragEffect = (DragSourceEffect) effect; + } else if (control instanceof Tree) { + dragEffect = new TreeDragSourceEffect((Tree) control); + } else if (control instanceof Table) { + dragEffect = new TableDragSourceEffect((Table) control); + } +} + +static int checkStyle (int style) { + if (style == SWT.NONE) return DND.DROP_MOVE; + return style; +} + +static int DragSendDataProc(int theType, int dragSendRefCon, int theItemRef, int theDrag) { + DragSource source = FindDragSource(dragSendRefCon, theDrag); + if (source == null) return OS.cantGetFlavorErr; + return source.dragSendDataProc(theType, dragSendRefCon, theItemRef, theDrag); +} + +static DragSource FindDragSource(int dragSendRefCon, int theDrag) { + if (dragSendRefCon == 0) return null; + Display display = Display.findDisplay(Thread.currentThread()); + if (display == null || display.isDisposed()) return null; + Widget widget = display.findWidget(dragSendRefCon); + if (widget == null) return null; + return (DragSource)widget.getData(DND.DRAG_SOURCE_KEY); +} + +/** + * Adds the listener to the collection of listeners who will + * be notified when a drag and drop operation is in progress, by sending + * it one of the messages defined in the <code>DragSourceListener</code> + * interface. + * + * <p><ul> + * <li><code>dragStart</code> is called when the user has begun the actions required to drag the widget. + * This event gives the application the chance to decide if a drag should be started. + * <li><code>dragSetData</code> is called when the data is required from the drag source. + * <li><code>dragFinished</code> is called when the drop has successfully completed (mouse up + * over a valid target) or has been terminated (such as hitting the ESC key). Perform cleanup + * such as removing data from the source side on a successful move operation. + * </ul></p> + * + * @param listener the listener which should be notified + * + * @exception IllegalArgumentException <ul> + * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> + * </ul> + * @exception SWTException <ul> + * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> + * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> + * </ul> + * + * @see DragSourceListener + * @see #getDragListeners + * @see #removeDragListener + * @see DragSourceEvent + */ +public void addDragListener(DragSourceListener listener) { + if (listener == null) DND.error (SWT.ERROR_NULL_ARGUMENT); + DNDListener typedListener = new DNDListener (listener); + typedListener.dndWidget = this; + addListener (DND.DragStart, typedListener); + addListener (DND.DragSetData, typedListener); + addListener (DND.DragEnd, typedListener); +} + +protected void checkSubclass () { + String name = getClass().getName (); + String validName = DragSource.class.getName(); + if (!validName.equals(name)) { + DND.error (SWT.ERROR_INVALID_SUBCLASS); + } +} + +void drag(Event dragEvent) { + DNDEvent event = new DNDEvent(); + event.widget = this; + event.x = dragEvent.x; + event.y = dragEvent.y; + event.time = dragEvent.time; + event.doit = true; + notifyListeners(DND.DragStart, event); + if (!event.doit || transferAgents == null || transferAgents.length == 0) return; + + int[] theDrag = new int[1]; + if (OS.NewDrag(theDrag) != OS.noErr) { + event = new DNDEvent(); + event.widget = this; + event.time = (int)System.currentTimeMillis(); + event.doit = false; + event.detail = DND.DROP_NONE; + notifyListeners(DND.DragEnd, event); + return; + } + + Point pt = new Point(); + OS.GetGlobalMouse (pt); + + for (int i = 0; i < transferAgents.length; i++) { + Transfer transfer = transferAgents[i]; + if (transfer != null) { + int[] types = transfer.getTypeIds(); + if (transfer instanceof FileTransfer) { + TransferData transferData = new TransferData(); + transferData.type = types[0]; + DNDEvent event2 = new DNDEvent(); + event2.widget = this; + event2.time = (int)System.currentTimeMillis(); + event2.dataType = transferData; + notifyListeners(DND.DragSetData, event2); + if (event2.data != null) { + for (int j = 0; j < types.length; j++) { + transferData.type = types[j]; + transfer.javaToNative(event2.data, transferData); + if (transferData.result == OS.noErr) { + for (int k = 0; k < transferData.data.length; k++) { + byte[] datum = transferData.data[k]; + OS.AddDragItemFlavor(theDrag[0], 1 + k, types[j], datum, datum.length, 0); + } + } + } + } + } else { + for (int j = 0; j < types.length; j++) { + OS.AddDragItemFlavor(theDrag[0], 1, types[j], null, 0, 0); + } + } + } + } + + OS.SetDragSendProc(theDrag[0], DragSendDataProc.getAddress(), control.handle); + + int theRegion = 0; + Image newImage = null; + try { + theRegion = OS.NewRgn(); + OS.SetRectRgn(theRegion, (short)(pt.h), (short)(pt.v), (short)(pt.h+20), (short)(pt.v+20)); + + int operations = opToOsOp(getStyle()); + //set operations twice - local and not local + OS.SetDragAllowableActions(theDrag[0], operations, true); + OS.SetDragAllowableActions(theDrag[0], operations, false); + + Image image = event.image; + if (image != null) { + CGPoint imageOffsetPt = new CGPoint(); + imageOffsetPt.x = 0; + imageOffsetPt.y = 0; + /* + * Bug in the Macintosh. For some reason, it seems that SetDragImageWithCGImage() + * expects an image with the alpha, otherwise the image does not draw. The fix is + * to make sure that the image has an alpha by creating a new image with alpha + * when necessary. + */ + if (OS.CGImageGetAlphaInfo(image.handle) == OS.kCGImageAlphaNoneSkipFirst) { + ImageData data = image.getImageData(); + data.alpha = 0xFF; + newImage = new Image(image.getDevice(), data); + image = newImage; + } + OS.SetDragImageWithCGImage(theDrag[0], image.handle, imageOffsetPt, 0); + } + EventRecord theEvent = new EventRecord(); + theEvent.message = OS.kEventMouseMoved; + theEvent.modifiers = (short)OS.GetCurrentEventKeyModifiers(); + theEvent.what = (short)OS.osEvt; + theEvent.where_h = pt.h; + theEvent.where_v = pt.v; + int result = OS.TrackDrag(theDrag[0], theEvent, theRegion); + int operation = DND.DROP_NONE; + if (result == OS.noErr) { + int[] outAction = new int[1]; + OS.GetDragDropAction(theDrag[0], outAction); + operation = osOpToOp(outAction[0]); + } + event = new DNDEvent(); + event.widget = this; + event.time = (int)System.currentTimeMillis(); + event.doit = result == OS.noErr; + event.detail = operation; + notifyListeners(DND.DragEnd, event); + } finally { + if (theRegion != 0) OS.DisposeRgn(theRegion); + if (newImage != null) newImage.dispose(); + } + OS.DisposeDrag(theDrag[0]); +} + +int dragSendDataProc(int theType, int dragSendRefCon, int theItemRef, int theDrag) { + if (theType == 0) return OS.badDragFlavorErr; + TransferData transferData = new TransferData(); + transferData.type = theType; + DNDEvent event = new DNDEvent(); + event.widget = this; + event.time = (int)System.currentTimeMillis(); + event.dataType = transferData; + notifyListeners(DND.DragSetData, event); + if (!event.doit) return OS.dragNotAcceptedErr; + Transfer transfer = null; + for (int i = 0; i < transferAgents.length; i++) { + Transfer transferAgent = transferAgents[i]; + if (transferAgent != null && transferAgent.isSupportedType(transferData)) { + transfer = transferAgent; + break; + } + } + if (transfer == null) return OS.badDragFlavorErr; + transfer.javaToNative(event.data, transferData); + if (transferData.result != OS.noErr) return transferData.result; + // Except for FileTransfer (see #drag), only one item can be transferred + // in a Drag operation + byte[] datum = transferData.data[0]; + if (datum == null) return OS.cantGetFlavorErr; + return OS.SetDragItemFlavorData(theDrag, theItemRef, theType, datum, datum.length, 0); +} + +/** + * Returns the Control which is registered for this DragSource. This is the control that the + * user clicks in to initiate dragging. + * + * @return the Control which is registered for this DragSource + */ +public Control getControl () { + return control; +} + +/** + * Returns an array of listeners who will be notified when a drag and drop + * operation is in progress, by sending it one of the messages defined in + * the <code>DragSourceListener</code> interface. + * + * @return the listeners who will be notified when a drag and drop + * operation is in progress + * + * @exception SWTException <ul> + * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> + * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> + * </ul> + * + * @see DragSourceListener + * @see #addDragListener + * @see #removeDragListener + * @see DragSourceEvent + * + * @since 3.4 + */ +public DragSourceListener[] getDragListeners() { + Listener[] listeners = getListeners(DND.DragStart); + int length = listeners.length; + DragSourceListener[] dragListeners = new DragSourceListener[length]; + int count = 0; + for (int i = 0; i < length; i++) { + Listener listener = listeners[i]; + if (listener instanceof DNDListener) { + dragListeners[count] = (DragSourceListener) ((DNDListener) listener).getEventListener(); + count++; + } + } + if (count == length) return dragListeners; + DragSourceListener[] result = new DragSourceListener[count]; + System.arraycopy(dragListeners, 0, result, 0, count); + return result; +} + +/** + * Returns the drag effect that is registered for this DragSource. This drag + * effect will be used during a drag and drop operation. + * + * @return the drag effect that is registered for this DragSource + * + * @since 3.3 + */ +public DragSourceEffect getDragSourceEffect() { + return dragEffect; +} + +/** + * Returns the list of data types that can be transferred by this DragSource. + * + * @return the list of data types that can be transferred by this DragSource + */ +public Transfer[] getTransfer(){ + return transferAgents; +} + +void onDispose() { + if (control == null) + return; + if (controlListener != null) { + control.removeListener(SWT.Dispose, controlListener); + control.removeListener(SWT.DragDetect, controlListener); + } + controlListener = null; + control.setData(DND.DRAG_SOURCE_KEY, null); + control = null; + transferAgents = null; +} + +int opToOsOp(int operation) { + int osOperation = 0; + if ((operation & DND.DROP_COPY) != 0){ + osOperation |= OS.kDragActionCopy; + } + if ((operation & DND.DROP_LINK) != 0) { + osOperation |= OS.kDragActionAlias; + } + if ((operation & DND.DROP_MOVE) != 0) { + osOperation |= OS.kDragActionMove; + } + if ((operation & DND.DROP_TARGET_MOVE) != 0) { + osOperation |= OS.kDragActionDelete; + } + return osOperation; +} + +int osOpToOp(int osOperation){ + int operation = 0; + if ((osOperation & OS.kDragActionCopy) != 0){ + operation |= DND.DROP_COPY; + } + if ((osOperation & OS.kDragActionAlias) != 0) { + operation |= DND.DROP_LINK; + } + if ((osOperation & OS.kDragActionDelete) != 0) { + operation |= DND.DROP_TARGET_MOVE; + } + if ((osOperation & OS.kDragActionMove) != 0) { + operation |= DND.DROP_MOVE; + } + if (osOperation == OS.kDragActionAll) { + operation = DND.DROP_COPY | DND.DROP_MOVE | DND.DROP_LINK; + } + return operation; +} + +/** + * Removes the listener from the collection of listeners who will + * be notified when a drag and drop operation is in progress. + * + * @param listener the listener which should no longer be notified + * + * @exception IllegalArgumentException <ul> + * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> + * </ul> + * @exception SWTException <ul> + * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> + * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> + * </ul> + * + * @see DragSourceListener + * @see #addDragListener + * @see #getDragListeners + */ +public void removeDragListener(DragSourceListener listener) { + if (listener == null) DND.error (SWT.ERROR_NULL_ARGUMENT); + removeListener (DND.DragStart, listener); + removeListener (DND.DragSetData, listener); + removeListener (DND.DragEnd, listener); +} + +/** + * Specifies the drag effect for this DragSource. This drag effect will be + * used during a drag and drop operation. + * + * @param effect the drag effect that is registered for this DragSource + * + * @since 3.3 + */ +public void setDragSourceEffect(DragSourceEffect effect) { + dragEffect = effect; +} +/** + * Specifies the list of data types that can be transferred by this DragSource. + * The application must be able to provide data to match each of these types when + * a successful drop has occurred. + * + * @param transferAgents a list of Transfer objects which define the types of data that can be + * dragged from this source + */ +public void setTransfer(Transfer[] transferAgents){ + this.transferAgents = transferAgents; +} + +} |