XtManageChildren(3Xt)XtManageChildren(3Xt)NAME
XtManageChildren, XtManageChild, XtUnmanageChildren, XtUnmanageChild,
XtChangeManagedSet, XtIsManaged - manage and unmanage children
SYNOPSIS
typedef Widget *WidgetList;
void XtManageChildren(children, num_children)
WidgetList children;
Cardinal num_children;
void XtManageChild(child)
Widget child;
void XtUnmanageChildren(children, num_children)
WidgetList children;
Cardinal num_children;
void XtUnmanageChild(child)
Widget child;
void XtChangeManagedSet(unmanage_children, num_unmanage_children, man‐
age_children, num_manage_children, post_unmanage_pre_manage_hook,
client_data)
WidgetList unmanage_children;
Cardinal num_unmanage_children;
WidgetList manage_children;
Cardinal num_manage_children;
XtCSMProc post_unmanage_pre_manage_hook;
XtPointer client_data;
Boolean XtIsManaged(widget)
Widget widget
ARGUMENTS
Specifies the child. Specifies a list of child widgets. Specifies the
number of children. Specifies the widget. Specifies the list of wid‐
get children to add to the managed set. Specifies the number of
entries in the manage_children list. Specifies the list of widget
children to remove from the managed set. Specifies the number of
entries in the unmanage_children list. Specifies the post unmanage,
pre manage hook procedure to invoke. Specifies the client data to be
passed to the hook procedure.
DESCRIPTION
The XtManageChildren function performs the following: Issues an error
if the children do not all have the same parent or if the parent is not
a subclass of compositeWidgetClass. Returns immediately if the common
parent is being destroyed; otherwise, for each unique child on the
list, XtManageChildren ignores the child if it already is managed or is
being destroyed and marks it if not. If the parent is realized and
after all children have been marked, it makes some of the newly managed
children viewable: Calls the change_managed routine of the widgets'
parent. Calls XtRealizeWidget on each previously unmanaged child that
is unrealized. Maps each previously unmanaged child that has
map_when_managed True.
Managing children is independent of the ordering of children and inde‐
pendent of creating and deleting children. The layout routine of the
parent should consider children whose managed field is True and should
ignore all other children. Note that some composite widgets, especially
fixed boxes, call XtManageChild from their insert_child procedure.
If the parent widget is realized, its change_managed procedure is
called to notify it that its set of managed children has changed. The
parent can reposition and resize any of its children. It moves each
child as needed by calling XtMoveWidget, which first updates the x and
y fields and then calls XMoveWindow if the widget is realized.
The XtManageChild function constructs a WidgetList of length one and
calls XtManageChildren.
The XtUnmanageChildren function performs the following: Issues an error
if the children do not all have the same parent or if the parent is not
a subclass of compositeWidgetClass. Returns immediately if the common
parent is being destroyed; otherwise, for each unique child on the
list, XtUnmanageChildren performs the following: Ignores the child if
it already is unmanaged or is being destroyed and marks it if not. If
the child is realized, it makes it nonvisible by unmapping it. Calls
the change_managed routine of the widgets' parent after all children
have been marked if the parent is realized.
XtUnmanageChildren does not destroy the children widgets. Removing wid‐
gets from a parent's managed set is often a temporary banishment, and,
some time later, you may manage the children again.
The XtUnmanageChild function constructs a widget list of length one and
calls XtUnmanageChildren.
The XtChangeManagedSet function performs the following: Issues an error
if the widgets specified in the manage_children and the unmanage_chil‐
dren lists to no all have the same parent, or if that parent is not a
subclass of compositeWidgetClass. Returns immediately if the common
parent is being destroyed. If no CompositeClassExtension is defined,
or a CompositeClassExtension is defined but with an allows_change_man‐
aged_set field with a value of False, and XtChangeManagedSet was
invoked with a non-NULL post_unmanage_pre_manage_hook procedure then
XtChangeManagedSet performs the following: Calls XtUnmanageChildren
(unmanage_children, num_unmanage_children). Calls the post_unman‐
age_pre_manage_hook specified. Calls XtManageChildren (manage_chil‐
dren, num_manage_children) and then returns immediately. Otherwise, if
a CompositeClassExtension is defined with an allows_change_managed_set
field with a value of True, or if no CompositeClassExtension is
defined, and XtChangeManagedSet was invoked with a NULL post_unman‐
age_pre_manage_hook procedure, then the following is performed: For
each child on the unmanage_children list; if the child is already
unmanaged or is being destroyed it is ignored, otherwise it is marked
as being unmanaged and if it is realized it is made nonvisible by being
unmapped. If the post_unmanage_pre_manage_hook procedure is non-NULL
then it is invoked as specified. For each child on the manage_children
list; if the child is already managed or it is being destroyed it is
ignored, otherwise it is marked as managed If the parent is realized
and after all children have been marked, the change_managed method of
the parent is invoked and subsequently some of the newly managed chil‐
dren are made viewable by: Calling XtRealizeWidget on each of the pre‐
viously unmanaged child that is unrealized. Mapping each previously
unmanaged child that has map_when_managed True.
The XtIsManaged function returns True if the specified widget is of
class RectObj or any subclass thereof and is managed, or False other‐
wise.
SEE ALSOXtMapWidget(3Xt), XtRealizeWidget(3Xt)
X Toolkit Intrinsics -- C Language Interface
Xlib -- C Language X Interface
XtManageChildren(3Xt)
