| /******************************************************************************* |
| * Copyright (c) 2000, 2011 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.widgets.*; |
| import org.eclipse.swt.internal.*; |
| import org.eclipse.swt.internal.motif.*; |
| |
| /** |
| * |
| * <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 ConvertProc; |
| static Callback DragDropFinish; |
| static Callback DropFinish; |
| static { |
| ConvertProc = new Callback(DragSource.class, "ConvertProcCallback", 10); //$NON-NLS-1$ |
| if (ConvertProc.getAddress() == 0) SWT.error(SWT.ERROR_NO_MORE_CALLBACKS); |
| DragDropFinish = new Callback(DragSource.class, "DragDropFinishCallback", 3); //$NON-NLS-1$ |
| if (DragDropFinish.getAddress() == 0) SWT.error(SWT.ERROR_NO_MORE_CALLBACKS); |
| DropFinish = new Callback(DragSource.class, "DropFinishCallback", 3); //$NON-NLS-1$ |
| if (DropFinish.getAddress() == 0) SWT.error(SWT.ERROR_NO_MORE_CALLBACKS); |
| } |
| boolean moveRequested; |
| |
| int dragContext; |
| |
| /** |
| * 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)); |
| if (ConvertProc == null || DragDropFinish == null || DropFinish == null) |
| DND.error(DND.ERROR_CANNOT_INIT_DRAG); |
| 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 DragSource FindDragSource(int handle) { |
| Display display = Display.findDisplay(Thread.currentThread()); |
| if (display == null || display.isDisposed()) return null; |
| return (DragSource)display.getData(Integer.toString(handle)); |
| } |
| static int ConvertProcCallback(int widget, int pSelection, int pTarget, int pType_return, int ppValue_return, int pLength_return, int pFormat_return, int max_length, int client_data, int request_id) { |
| DragSource source = FindDragSource(widget); |
| if (source == null) return 0; |
| return source.convertProcCallback(widget, pSelection, pTarget, pType_return, ppValue_return, pLength_return, pFormat_return, max_length, client_data, request_id); |
| } |
| static int DragDropFinishCallback(int widget, int client_data, int call_data) { |
| DragSource source = FindDragSource(widget); |
| if (source == null) return 0; |
| return source.dragDropFinishCallback(widget, client_data, call_data); |
| } |
| static int DropFinishCallback(int widget, int client_data, int call_data) { |
| DragSource source = FindDragSource(widget); |
| if (source == null) return 0; |
| return source.dropFinishCallback(widget, client_data, call_data); |
| } |
| /** |
| * 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); |
| } |
| |
| static int checkStyle (int style) { |
| if (style == SWT.NONE) return DND.DROP_MOVE; |
| return style; |
| } |
| |
| protected void checkSubclass () { |
| String name = getClass().getName (); |
| String validName = DragSource.class.getName(); |
| if (!validName.equals(name)) { |
| DND.error (SWT.ERROR_INVALID_SUBCLASS); |
| } |
| } |
| |
| int convertProcCallback(int widget, int pSelection, int pTarget, int pType_return, int ppValue_return, int pLength_return, int pFormat_return, int max_length, int client_data, int request_id) { |
| if (pSelection == 0 ) return 0; |
| |
| // is this a drop? |
| int[] selection = new int[1]; |
| OS.memmove(selection, pSelection, 4); |
| int xDisplay = getDisplay().xDisplay; |
| byte[] bName = Converter.wcsToMbcs (null, "_MOTIF_DROP", true); //$NON-NLS-1$ |
| int motifDropAtom = OS.XmInternAtom (xDisplay, bName, true); |
| if (selection[0] != motifDropAtom) return 0; |
| |
| // get the target value from pTarget |
| int[] target = new int[1]; |
| OS.memmove(target, pTarget, 4); |
| |
| // handle the "Move" case |
| bName = Converter.wcsToMbcs (null, "DELETE", true); // DELETE corresponds to a Move request //$NON-NLS-1$ |
| int deleteAtom = OS.XmInternAtom (xDisplay, bName, true); |
| if (target[0] == deleteAtom) { |
| moveRequested = true; |
| bName = Converter.wcsToMbcs (null, "NULL", true); //$NON-NLS-1$ |
| int nullAtom = OS.XmInternAtom (xDisplay, bName, true); |
| OS.memmove(pType_return,new int[]{nullAtom}, 4); |
| OS.memmove(ppValue_return, new int[]{0}, 4); |
| OS.memmove(pLength_return, new int[]{0}, 4); |
| OS.memmove(pFormat_return, new int[]{8}, 4); |
| return 1; |
| } |
| |
| // do we support the requested data type? |
| boolean dataMatch = false; |
| TransferData transferData = new TransferData(); |
| transferData.type = target[0]; |
| for (int i = 0; i < transferAgents.length; i++){ |
| Transfer transfer = transferAgents[i]; |
| if (transfer != null && transfer.isSupportedType(transferData)){ |
| dataMatch = true; |
| break; |
| } |
| } |
| if (!dataMatch) return 0; |
| |
| DNDEvent event = new DNDEvent(); |
| event.widget = control; |
| //event.time = ??; |
| event.dataType = transferData; |
| notifyListeners(DND.DragSetData,event); |
| |
| if (!event.doit) return 0; |
| Transfer transferAgent = null; |
| for (int i = 0; i < transferAgents.length; i++){ |
| Transfer transfer = transferAgents[i]; |
| if (transfer != null && transfer.isSupportedType(transferData)){ |
| transferAgent = transfer; |
| break; |
| } |
| } |
| if (transferAgent == null) return 0; |
| |
| transferAgent.javaToNative(event.data, transferData); |
| if (transferData.result == 1){ |
| OS.memmove(ppValue_return, new int[]{transferData.pValue}, 4); |
| OS.memmove(pType_return, new int[]{transferData.type}, 4); |
| OS.memmove(pLength_return, new int[]{transferData.length}, 4); |
| OS.memmove(pFormat_return, new int[]{transferData.format}, 4); |
| return 1; |
| } |
| OS.memmove(ppValue_return, new int[]{0}, 4); |
| OS.memmove(pLength_return, new int[]{0}, 4); |
| OS.memmove(pFormat_return, new int[]{8}, 4); |
| return 0; |
| } |
| void drag(Event dragEvent) { |
| moveRequested = false; |
| // Current event must be a Button Press event |
| Display display = control.getDisplay (); |
| XButtonEvent xEvent = new XButtonEvent(); |
| OS.memmove(xEvent, display.xEvent, XButtonEvent.sizeof); |
| if (xEvent.type != OS.ButtonPress) return; |
| |
| DNDEvent event = new DNDEvent(); |
| event.widget = this; |
| event.x = dragEvent.x; |
| event.y = dragEvent.y; |
| event.time = xEvent.time; |
| event.doit = true; |
| notifyListeners(DND.DragStart, event); |
| if (!event.doit || transferAgents == null || transferAgents.length == 0) { |
| int time = xEvent.time; |
| int dc = OS.XmGetDragContext(control.handle, time); |
| if (dc != 0){ |
| OS.XmDragCancel(dc); |
| } |
| return; |
| } |
| |
| // set the protocol (optional) |
| // not implemented |
| |
| // create pixmaps for icons (optional) |
| // not implemented |
| |
| // Copy targets to global memory |
| TransferData[] transferData = new TransferData[0]; |
| for (int i = 0; i < transferAgents.length; i++){ |
| Transfer transfer = transferAgents[i]; |
| if (transfer != null) { |
| TransferData[] data = transfer.getSupportedTypes(); |
| TransferData[] newTransferData = new TransferData[transferData.length + data.length]; |
| System.arraycopy(transferData, 0, newTransferData, 0, transferData.length); |
| System.arraycopy(data, 0, newTransferData, transferData.length, data.length); |
| transferData = newTransferData; |
| } |
| } |
| int[] dataTypes = new int[transferData.length]; |
| for (int i = 0; i < transferData.length; i++){ |
| dataTypes[i] = transferData[i].type; |
| } |
| int pExportTargets = OS.XtMalloc(dataTypes.length * 4); |
| OS.memmove(pExportTargets, dataTypes, dataTypes.length * 4); |
| |
| int[] args = new int[]{ |
| OS.XmNexportTargets, pExportTargets, |
| OS.XmNnumExportTargets, dataTypes.length, |
| OS.XmNdragOperations, opToOsOp(getStyle()), |
| OS.XmNconvertProc, ConvertProc.getAddress(), |
| OS.XmNoperationCursorIcon, 0, |
| OS.XmNsourceCursorIcon, 0, |
| OS.XmNstateCursorIcon, 0, |
| OS.XmNclientData, 0, |
| OS.XmNblendModel, OS.XmBLEND_ALL |
| }; |
| |
| // look for existing drag contexts |
| int time = xEvent.time; |
| dragContext = OS.XmGetDragContext(control.handle, time); |
| if (dragContext != 0){ |
| OS.XtSetValues(dragContext, args, args.length /2); |
| } else { |
| dragContext = OS.XmDragStart(this.control.handle, display.xEvent, args, args.length / 2); |
| } |
| OS.XtFree(pExportTargets); |
| if (dragContext == 0) return; |
| |
| // register a call back to clean up when drop is done (optional) |
| OS.XtAddCallback(dragContext, OS.XmNdragDropFinishCallback, DragDropFinish.getAddress(), 0); |
| |
| // register a call back to tell user what happened (optional) |
| OS.XtAddCallback(dragContext, OS.XmNdropFinishCallback, DropFinish.getAddress(), 0); |
| |
| display.setData(Integer.toString(dragContext), this); |
| return; |
| } |
| |
| int dragDropFinishCallback(int widget, int client_data, int call_data) { |
| |
| // uncomment the following code when we allow users to specify their own source icons |
| // release the pre set source icon |
| //int pSourceIcon = OS.XtMalloc(4); |
| //int[] args = new int[]{OS.XmNsourceCursorIcon, pSourceIcon}; |
| //OS.XtGetValues(control.handle, args, args.length / 2); |
| //int[] sourceIcon = new int[1]; |
| //OS.memmove(sourceIcon, pSourceIcon, 4); |
| //if (sourceIcon[0] != 0) |
| //OS.XtDestroyWidget(sourceIcon[0]); |
| //OS.XtFree(pSourceIcon); |
| |
| dragContext = 0; |
| getDisplay().setData(Integer.toString(dragContext), null); |
| return 0; |
| } |
| int dropFinishCallback(int widget, int client_data, int call_data) { |
| XmDropFinishCallbackStruct data = new XmDropFinishCallbackStruct(); |
| OS.memmove(data, call_data, XmDropFinishCallbackStruct.sizeof); |
| if (data.dropAction != OS.XmDROP || data.dropSiteStatus != OS.XmDROP_SITE_VALID) { |
| DNDEvent event = new DNDEvent(); |
| event.widget = this.control; |
| event.time = data.timeStamp; |
| event.detail = DND.DROP_NONE; |
| event.doit = false; |
| notifyListeners(DND.DragEnd,event); |
| return 0; |
| } |
| DNDEvent event = new DNDEvent(); |
| event.widget = this.control; |
| event.time = data.timeStamp; |
| if (moveRequested) { |
| event.detail = DND.DROP_MOVE; |
| } else { |
| if (data.operation == OS.XmDROP_MOVE) { |
| event.detail = DND.DROP_NONE; |
| } else { |
| event.detail = osOpToOp(data.operation); |
| } |
| } |
| event.doit = (data.completionStatus != 0); |
| notifyListeners(DND.DragEnd,event); |
| moveRequested = false; |
| return 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; |
| } |
| byte opToOsOp(int operation){ |
| byte osOperation = OS.XmDROP_NOOP; |
| |
| if ((operation & DND.DROP_COPY) == DND.DROP_COPY) |
| osOperation |= OS.XmDROP_COPY; |
| if ((operation & DND.DROP_MOVE) == DND.DROP_MOVE) |
| osOperation |= OS.XmDROP_MOVE; |
| if ((operation & DND.DROP_LINK) == DND.DROP_LINK) |
| osOperation |= OS.XmDROP_LINK; |
| |
| return osOperation; |
| } |
| int osOpToOp(byte osOperation){ |
| int operation = DND.DROP_NONE; |
| |
| if ((osOperation & OS.XmDROP_COPY) == OS.XmDROP_COPY) |
| operation |= DND.DROP_COPY; |
| if ((osOperation & OS.XmDROP_MOVE) == OS.XmDROP_MOVE) |
| operation |= DND.DROP_MOVE; |
| if ((osOperation & OS.XmDROP_LINK) == OS.XmDROP_LINK) |
| operation |= 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; |
| } |
| |
| } |