Experimental Physics and
Industrial Control System

Thomas Birke <[email protected]> · Fri, 17 Apr 1998 11:30:04 +0200 (METDST)

>>>>> "Bonnie" == Bonnie Madre <[email protected]> writes:

 Bonnie> When I create a related display, and fill in the grid for screens
 Bonnie> to access, and then hit the "Close" button, I get the following
 Bonnie> message:

 Bonnie> Attempt to unmanage a child when parent is not Composite

Thanks to Noboru Yamamoto, he might have found the bug!

Although we (Noboru and I) both cannot reproduce this behaviour (on HP-UX
10.20), it seems reasonable:

Noboru compared the implementations of the close-button in medm-2.3.3 and
medm/DESY-2.4.9.

medm-2.3.3, medmRelatedDisplay.c, line 884 ff.:

    case RD_CLOSE_BTN:
	if (XtClass(w) == xmPushButtonWidgetClass) {
	    XtPopdown(relatedDisplayS);
	    XtUnmanageChild(relatedDisplayS);
	}
	break;

medm/DESY-2.4.9, medmRelatedDisplay.c, line 1354 ff.:

    case RD_CLOSE_BTN:
      if (XtClass(w) == xmPushButtonWidgetClass) {
	XtPopdown(relatedDisplayS);
      }
      break;

The corresponding part of code in both cases is (lines 1052 resp. 1556 ff):

  XtManageChild(rdForm);
  XtPopup(relatedDisplayS,XtGrabNone);

It seems that both close-implementations are not correct, because
medm-2.3.3 tries to unmamage a child, that has never been managed and
medm/DESY-2.4.9 never unmanages the managed child.

My suggestion (esp. for all Linux, Digital Unix and NT users) would be to
replace this part of code with:

medmRelatedDisplay.c, line 884 resp. 1354 ff.:

    case RD_CLOSE_BTN:
      if (XtClass(w) == xmPushButtonWidgetClass) {
	XtPopdown(relatedDisplayS);
        XtUnmanageChild(rdForm);
      }
      break;

To see wether it solves the problem.

So long,
Thomas

-- 
_______________________________________________________________________________
 /homas Birke  BESSY II   (+49)-30-6392-4934 (fax -4859)    [email protected]

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System