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Orange Widgets
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XtCallAcceptFocus() XtCallAcceptFocus() Name XtCallAcceptFocus - offer the input focus to a child widget. Synopsis Boolean XtCallAcceptFocus(w, time) Widget w; Time *time; Inputs w Specifies the widget; must be of class Core or any subclass thereof. time Specifies the X time of the event that is causing the accept focus. Returns True if w took the input focus; False if w did not take the input focus. Description XtCallAcceptFocus() calls the specified widget's Core class accept_focus() method, passing it the specified widget and time, and True if the widget took the input focus, or False otherwise. If the accept_focus() method is NULL, XtCallAcceptFocus() returns False. Usage Generally, only widgets should call XtCallAcceptFocus(), and generally only on their descendants. Note that calling a widget's accept_focus() method does not automatically assign the input focus, and does not mean that the widget will necessarily take the input focus. The accept_focus() method must decide whether or not to take the focus and then take it with XSetInput- Focus() or XtSetKeyboardFocus(). Background Widgets that need the input focus can call XSetInputFocus() explicitly, pursuant to the restrictions of the Inter-Client Communications Convention Manual. To allow outside agents, such as the parent, to cause a widget to take the input focus, every widget exports an accept_focus() method. The widget returns a value indicating whether it actually took the focus or not, so that the parent can give the focus to another widget. Widgets that need to know when they lose the input focus must use the Xlib focus notification mechanism explic- itly (typically by specifying translations for FocusIn and FocusOut events). Widget classes that never want the input focus should set the accept_focus() method to NULL. See Also XtSetKeyboardFocus(1), accept_focus(4). Xt - Keyboard Handling XtCallAcceptFocus()
