accept_focu(3x) — HP-UX ANSI C A.10.11

NAME

accept_focus − Core class method for accepting or rejecting the keyboard focus.

Synopsis

typedef Boolean (*XtAcceptFocusProc)(Widget, Time *);

Widget w;
Time *time;

Inputs

wSpecifies the widget.

timeSpecifies the X time of the event causing the parent to offer focus to the child.

Returns

True if the child actually took the focus; False otherwise.

Description

The accept_focus() method is registered on the accept_focus() field of the Core class part structure and is invoked by XtCallAcceptFocus() when a parent widget wants to offer keyboard focus to a the widget. If the widget wants the keyboard focus, it should take it with the Xlib function XSetInputFocus() and return True. If the widget does not currently want the focus, it should return False. The ICCCM requires that a widget use Parent for the revert_to argument to XSetInputFocus(). The accept_focus() method is not chained. If a widget class does not define an accept_focus() method, it can use XtInheritAcceptFocus to inherit the method from its superclass. If the widget never wants the focus, it should have an accept_focus() field of NULL.

Usage

Note that this method is an invitation to take the focus, not notification that focus has changed, and not a command to take the focus. A widget that needs to know when it loses the focus can specify translations or event handlers for FocusIn and FocusOut events. None of the Intrinsics or Xaw widget classes define an accept_focus() method, and none of them ever call XtCallAcceptFocus(). An application that wants to direct keyboard events to a particular widget should use XtSetKeyboardFocus().

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