private int GetData(long /*int*/ pFormatetc, long /*int*/ pmedium) {
/* Called by a data consumer to obtain data from a source data object.
The GetData method renders the data described in the specified FORMATETC
structure and transfers it through the specified STGMEDIUM structure.
The caller then assumes responsibility for releasing the STGMEDIUM structure.
*/
if (pFormatetc == 0 || pmedium == 0) return COM.E_INVALIDARG;
if (QueryGetData(pFormatetc) != COM.S_OK) return COM.DV_E_FORMATETC;
TransferData transferData = new TransferData();
transferData.formatetc = new FORMATETC();
COM.MoveMemory(transferData.formatetc, pFormatetc, FORMATETC.sizeof);
transferData.type = transferData.formatetc.cfFormat;
transferData.stgmedium = new STGMEDIUM();
transferData.result = COM.E_FAIL;
DNDEvent event = new DNDEvent();
event.widget = this;
event.time = OS.GetMessageTime();
event.dataType = transferData;
notifyListeners(DND.DragSetData, event);
if (!event.doit) return COM.E_FAIL;
// get matching transfer agent to perform conversion
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 COM.DV_E_FORMATETC;
transfer.javaToNative(event.data, transferData);
if (transferData.result != COM.S_OK) return transferData.result;
COM.MoveMemory(pmedium, transferData.stgmedium, STGMEDIUM.sizeof);
return transferData.result;
}
private void drag(Event dragEvent) {
DNDEvent event = new DNDEvent();
event.widget = this;
event.x = dragEvent.x;
event.y = dragEvent.y;
event.time = OS.GetMessageTime();
event.doit = true;
notifyListeners(DND.DragStart, event);
if (!event.doit || transferAgents == null || transferAgents.length == 0) return;
int[] pdwEffect = new int[1];
int operations = opToOs(getStyle());
Display display = control.getDisplay();
String key = "org.eclipse.swt.internal.win32.runMessagesInIdle"; // $NON-NLS-1$
Object oldValue = display.getData(key);
display.setData(key, Boolean.TRUE);
ImageList imagelist = null;
Image image = event.image;
hwndDrag = 0;
topControl = null;
if (image != null) {
imagelist = new ImageList(SWT.NONE);
imagelist.add(image);
topControl = control.getShell();
/*
* Bug in Windows. The image is inverted if the shell is RIGHT_TO_LEFT.
* The fix is to create a transparent window that covers the shell client
* area and use it during the drag to prevent the image from being inverted.
* On XP if the shell is RTL, the image is not displayed.
*/
int offsetX = event.offsetX;
hwndDrag = topControl.handle;
if ((topControl.getStyle() & SWT.RIGHT_TO_LEFT) != 0) {
offsetX = image.getBounds().width - offsetX;
RECT rect = new RECT();
OS.GetClientRect(topControl.handle, rect);
hwndDrag =
OS.CreateWindowEx(
OS.WS_EX_TRANSPARENT | OS.WS_EX_NOINHERITLAYOUT,
WindowClass,
null,
OS.WS_CHILD | OS.WS_CLIPSIBLINGS,
0,
0,
rect.right - rect.left,
rect.bottom - rect.top,
topControl.handle,
0,
OS.GetModuleHandle(null),
null);
OS.ShowWindow(hwndDrag, OS.SW_SHOW);
}
OS.ImageList_BeginDrag(imagelist.getHandle(), 0, offsetX, event.offsetY);
/*
* Feature in Windows. When ImageList_DragEnter() is called,
* it takes a snapshot of the screen If a drag is started
* when another window is in front, then the snapshot will
* contain part of the other window, causing pixel corruption.
* The fix is to force all paints to be delivered before
* calling ImageList_DragEnter().
*/
if (OS.IsWinCE) {
OS.UpdateWindow(topControl.handle);
} else {
int flags = OS.RDW_UPDATENOW | OS.RDW_ALLCHILDREN;
OS.RedrawWindow(topControl.handle, null, 0, flags);
}
POINT pt = new POINT();
pt.x = dragEvent.x;
pt.y = dragEvent.y;
OS.MapWindowPoints(control.handle, 0, pt, 1);
RECT rect = new RECT();
OS.GetWindowRect(hwndDrag, rect);
OS.ImageList_DragEnter(hwndDrag, pt.x - rect.left, pt.y - rect.top);
}
int result = COM.DRAGDROP_S_CANCEL;
try {
result =
COM.DoDragDrop(iDataObject.getAddress(), iDropSource.getAddress(), operations, pdwEffect);
} finally {
// ensure that we don't leave transparent window around
if (hwndDrag != 0) {
OS.ImageList_DragLeave(hwndDrag);
OS.ImageList_EndDrag();
imagelist.dispose();
if (hwndDrag != topControl.handle) OS.DestroyWindow(hwndDrag);
hwndDrag = 0;
topControl = null;
}
display.setData(key, oldValue);
}
int operation = osToOp(pdwEffect[0]);
if (dataEffect == DND.DROP_MOVE) {
operation =
(operation == DND.DROP_NONE || operation == DND.DROP_COPY)
? DND.DROP_TARGET_MOVE
: DND.DROP_MOVE;
} else {
if (dataEffect != DND.DROP_NONE) {
operation = dataEffect;
}
}
event = new DNDEvent();
event.widget = this;
event.time = OS.GetMessageTime();
event.doit = (result == COM.DRAGDROP_S_DROP);
event.detail = operation;
notifyListeners(DND.DragEnd, event);
dataEffect = DND.DROP_NONE;
}