void XtManageChildren(children, num_children)
void XtUnmanageChildren(children, num_children)
void XtChangeManagedSet(unmanage_children, num_unmanage_children, manage_children,
num_manage_children, post_unmanage_pre_manage_hook, client_data)
- 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 independent 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:
- 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.
XtUnmanageChildren does not destroy the children widgets. Removing widgets 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:
- Calls XtUnmanageChildren (unmanage_children, num_unmanage_children).
- Calls the post_unmanage_pre_manage_hook specified.
- Calls XtManageChildren (manage_children, num_manage_children) and then returns immediately.
- 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 procdedure 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
- Calling XtRealizeWidget on each of the previously 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 otherwise.XtMapWidget(3Xt) , XtRealizeWidget(3Xt)