/**
* Displays the Tracker rectangles for manipulation by the user. Returns when the user has either
* finished manipulating the rectangles or has cancelled the Tracker.
*
* @return <code>true</code> if the user did not cancel the Tracker, <code>false</code> otherwise
* @exception SWTException
* <ul>
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
* </ul>
*/
public boolean open() {
checkWidget();
int xDisplay = display.xDisplay;
window = OS.XDefaultRootWindow(xDisplay);
if (parent != null) {
window = OS.XtWindow(parent.handle);
if (window == 0) return false;
}
cancelled = false;
tracking = true;
update();
drawRectangles(rectangles, stippled);
int[] oldX = new int[1], oldY = new int[1];
int[] unused = new int[1], mask = new int[1];
OS.XQueryPointer(xDisplay, window, unused, unused, oldX, oldY, unused, unused, mask);
/*
* If exactly one of UP/DOWN is specified as a style then set the cursor
* orientation accordingly (the same is done for LEFT/RIGHT styles below).
*/
int vStyle = style & (SWT.UP | SWT.DOWN);
if (vStyle == SWT.UP || vStyle == SWT.DOWN) {
cursorOrientation |= vStyle;
}
int hStyle = style & (SWT.LEFT | SWT.RIGHT);
if (hStyle == SWT.LEFT || hStyle == SWT.RIGHT) {
cursorOrientation |= hStyle;
}
int mouseMasks = OS.Button1Mask | OS.Button2Mask | OS.Button3Mask;
boolean mouseDown = (mask[0] & mouseMasks) != 0;
if (!mouseDown) {
Point cursorPos = null;
if ((style & SWT.RESIZE) != 0) {
cursorPos = adjustResizeCursor();
} else {
cursorPos = adjustMoveCursor();
}
if (cursorPos != null) {
oldX[0] = cursorPos.x;
oldY[0] = cursorPos.y;
}
}
this.oldX = oldX[0];
this.oldY = oldY[0];
int ptrGrabResult =
OS.XGrabPointer(
xDisplay,
window,
0,
OS.ButtonPressMask | OS.ButtonReleaseMask | OS.PointerMotionMask,
OS.GrabModeAsync,
OS.GrabModeAsync,
OS.None,
OS.None,
OS.CurrentTime);
int kbdGrabResult =
OS.XGrabKeyboard(xDisplay, window, 0, OS.GrabModeAsync, OS.GrabModeAsync, OS.CurrentTime);
/* Tracker behaves like a Dialog with its own OS event loop. */
XAnyEvent anyEvent = new XAnyEvent();
int xEvent = OS.XtMalloc(XEvent.sizeof);
int dispatch = OS.XtMalloc(4);
int xtContext = OS.XtDisplayToApplicationContext(xDisplay);
while (tracking) {
if (parent != null && parent.isDisposed()) break;
OS.XtAppNextEvent(xtContext, xEvent);
OS.memmove(anyEvent, xEvent, XAnyEvent.sizeof);
int widget = OS.XtWindowToWidget(anyEvent.display, anyEvent.window);
switch (anyEvent.type) {
case OS.MotionNotify:
XPointerMotion(widget, 0, xEvent, dispatch);
break;
case OS.ButtonRelease:
XButtonRelease(widget, 0, xEvent, dispatch);
break;
case OS.KeyPress:
XKeyPress(widget, 0, xEvent, dispatch);
break;
case OS.KeyRelease:
XKeyRelease(widget, 0, xEvent, dispatch);
break;
case OS.ButtonPress:
case OS.EnterNotify:
case OS.LeaveNotify:
/* Do not dispatch these */
break;
case OS.Expose:
update();
drawRectangles(rectangles, stippled);
OS.XtDispatchEvent(xEvent);
drawRectangles(rectangles, stippled);
break;
default:
OS.XtDispatchEvent(xEvent);
}
}
if (xEvent != 0) OS.XtFree(xEvent);
if (dispatch != 0) OS.XtFree(dispatch);
if (!isDisposed()) {
update();
drawRectangles(rectangles, stippled);
}
if (ptrGrabResult == OS.GrabSuccess) OS.XUngrabPointer(xDisplay, OS.CurrentTime);
if (kbdGrabResult == OS.GrabSuccess) OS.XUngrabKeyboard(xDisplay, OS.CurrentTime);
window = 0;
return !cancelled;
}
