tkfocus.c

linux系统下的音频通信

 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

TkWindow *
TkGetFocusWin(winPtr)
    TkWindow *winPtr;		/* Window that selects an application
				 * and a display. */
{
    DisplayFocusInfo *displayFocusPtr;

    if (winPtr == NULL) {
	return (TkWindow *) NULL;
    }

    displayFocusPtr = FindDisplayFocusInfo(winPtr->mainPtr, winPtr->dispPtr);
    return displayFocusPtr->focusWinPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * TkFocusKeyEvent --
 *
 *	Given a window and a key press or release event that arrived for
 *	the window, use information about the keyboard focus to compute
 *	which window should really get the event.  In addition, update
 *	the event to refer to its new window.
 *
 * Results:
 *	The return value is a pointer to the window that has the input
 *	focus in winPtr's application, or NULL if winPtr's application
 *	doesn't have the input focus.  If a non-NULL value is returned,
 *	eventPtr will be updated to refer properly to the focus window.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

TkWindow *
TkFocusKeyEvent(winPtr, eventPtr)
    TkWindow *winPtr;		/* Window that selects an application
				 * and a display. */
    XEvent *eventPtr;		/* X event to redirect (should be KeyPress
				 * or KeyRelease). */
{
    DisplayFocusInfo *displayFocusPtr;
    TkWindow *focusWinPtr;
    int focusX, focusY, vRootX, vRootY, vRootWidth, vRootHeight;

    displayFocusPtr = FindDisplayFocusInfo(winPtr->mainPtr, winPtr->dispPtr);
    focusWinPtr = displayFocusPtr->focusWinPtr;

    /*
     * The code below is a debugging aid to make sure that dispPtr->focusPtr
     * is kept properly in sync with the "truth", which is the value in
     * displayFocusPtr->focusWinPtr.
     */

#ifdef TCL_MEM_DEBUG
    if (focusWinPtr != winPtr->dispPtr->focusPtr) {
	printf("TkFocusKeyEvent found dispPtr->focusPtr out of sync:\n");
	printf("expected %s, got %s\n",
		(focusWinPtr != NULL) ? focusWinPtr->pathName : "??",
		(winPtr->dispPtr->focusPtr != NULL) ?
		winPtr->dispPtr->focusPtr->pathName : "??");
    }
#endif

    if ((focusWinPtr != NULL) && (focusWinPtr->mainPtr == winPtr->mainPtr)) {
	/*
	 * Map the x and y coordinates to make sense in the context of
	 * the focus window, if possible (make both -1 if the map-from
	 * and map-to windows don't share the same screen).
	 */

	if ((focusWinPtr->display != winPtr->display)
		|| (focusWinPtr->screenNum != winPtr->screenNum)) {
	    eventPtr->xkey.x = -1;
	    eventPtr->xkey.y = -1;
	} else {
	    Tk_GetVRootGeometry((Tk_Window) focusWinPtr, &vRootX, &vRootY,
		    &vRootWidth, &vRootHeight);
	    Tk_GetRootCoords((Tk_Window) focusWinPtr, &focusX, &focusY);
	    eventPtr->xkey.x = eventPtr->xkey.x_root - vRootX - focusX;
	    eventPtr->xkey.y = eventPtr->xkey.y_root - vRootY - focusY;
	}
	eventPtr->xkey.window = focusWinPtr->window;
	return focusWinPtr;
    }

    /*
     * The event doesn't belong to us.  Perhaps, due to embedding, it
     * really belongs to someone else.  Give the embedding code a chance
     * to redirect the event.
     */

    TkpRedirectKeyEvent(winPtr, eventPtr);
    return (TkWindow *) NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * TkFocusDeadWindow --
 *
 *	This procedure is invoked when it is determined that
 *	a window is dead.  It cleans up focus-related information
 *	about the window.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Various things get cleaned up and recycled.
 *
 *----------------------------------------------------------------------
 */

void
TkFocusDeadWindow(winPtr)
    register TkWindow *winPtr;		/* Information about the window
					 * that is being deleted. */
{
    ToplevelFocusInfo *tlFocusPtr, *prevPtr;
    DisplayFocusInfo *displayFocusPtr;
    TkDisplay *dispPtr = winPtr->dispPtr;

    /*
     * Search for focus records that refer to this window either as
     * the top-level window or the current focus window.
     */

    displayFocusPtr = FindDisplayFocusInfo(winPtr->mainPtr, winPtr->dispPtr);
    for (prevPtr = NULL, tlFocusPtr = winPtr->mainPtr->tlFocusPtr;
	    tlFocusPtr != NULL;
	    prevPtr = tlFocusPtr, tlFocusPtr = tlFocusPtr->nextPtr) {
	if (winPtr == tlFocusPtr->topLevelPtr) {
	    /*
	     * The top-level window is the one being deleted: free
	     * the focus record and release the focus back to PointerRoot
	     * if we acquired it implicitly.
	     */

	    if (dispPtr->implicitWinPtr == winPtr) {
		if (tclFocusDebug) {
		    printf("releasing focus to root after %s died\n",
			    tlFocusPtr->topLevelPtr->pathName);
		}
		dispPtr->implicitWinPtr = NULL;
		displayFocusPtr->focusWinPtr = NULL;
		dispPtr->focusPtr = NULL;
	    }
	    if (displayFocusPtr->focusWinPtr == tlFocusPtr->focusWinPtr) {
		displayFocusPtr->focusWinPtr = NULL;
		dispPtr->focusPtr = NULL;
	    }
	    if (prevPtr == NULL) {
		winPtr->mainPtr->tlFocusPtr = tlFocusPtr->nextPtr;
	    } else {
		prevPtr->nextPtr = tlFocusPtr->nextPtr;
	    }
	    ckfree((char *) tlFocusPtr);
	    break;
	} else if (winPtr == tlFocusPtr->focusWinPtr) {
	    /*
	     * The deleted window had the focus for its top-level:
	     * move the focus to the top-level itself.
	     */

	    tlFocusPtr->focusWinPtr = tlFocusPtr->topLevelPtr;
	    if ((displayFocusPtr->focusWinPtr == winPtr)
		    && !(tlFocusPtr->topLevelPtr->flags & TK_ALREADY_DEAD)) {
		if (tclFocusDebug) {
		    printf("forwarding focus to %s after %s died\n",
			    tlFocusPtr->topLevelPtr->pathName,
			    winPtr->pathName);
		}
		GenerateFocusEvents(displayFocusPtr->focusWinPtr,
			tlFocusPtr->topLevelPtr);
		displayFocusPtr->focusWinPtr = tlFocusPtr->topLevelPtr;
		dispPtr->focusPtr = tlFocusPtr->topLevelPtr;
	    }
	    break;
	}
    }

    if (displayFocusPtr->focusOnMapPtr == winPtr) {
	displayFocusPtr->focusOnMapPtr = NULL;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * GenerateFocusEvents --
 *
 *	This procedure is called to create FocusIn and FocusOut events to
 *	move the input focus from one window to another.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	FocusIn and FocusOut events are generated.
 *
 *----------------------------------------------------------------------
 */

static void
GenerateFocusEvents(sourcePtr, destPtr)
    TkWindow *sourcePtr;	/* Window that used to have the focus (may
				 * be NULL). */
    TkWindow *destPtr;		/* New window to have the focus (may be
				 * NULL). */

{
    XEvent event;
    TkWindow *winPtr;

    winPtr = sourcePtr;
    if (winPtr == NULL) {
	winPtr = destPtr;
	if (winPtr == NULL) {
	    return;
	}
    }

    event.xfocus.serial = LastKnownRequestProcessed(winPtr->display);
    event.xfocus.send_event = GENERATED_EVENT_MAGIC;
    event.xfocus.display = winPtr->display;
    event.xfocus.mode = NotifyNormal;
    TkInOutEvents(&event, sourcePtr, destPtr, FocusOut, FocusIn,
	    TCL_QUEUE_MARK);
}

/*
 *----------------------------------------------------------------------
 *
 * FocusMapProc --
 *
 *	This procedure is called as an event handler for VisibilityNotify
 *	events, if a window receives the focus at a time when its
 *	toplevel isn't mapped.  The procedure is needed because X
 *	won't allow the focus to be set to an unmapped window;  we
 *	detect when the toplevel is mapped and set the focus to it then.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	If this is a map event, the focus gets set to the toplevel
 *	given by clientData.
 *
 *----------------------------------------------------------------------
 */

static void
FocusMapProc(clientData, eventPtr)
    ClientData clientData;	/* Toplevel window. */
    XEvent *eventPtr;		/* Information about event. */
{
    TkWindow *winPtr = (TkWindow *) clientData;
    DisplayFocusInfo *displayFocusPtr;

    if (eventPtr->type == VisibilityNotify) {
	displayFocusPtr = FindDisplayFocusInfo(winPtr->mainPtr,
		winPtr->dispPtr);
	if (tclFocusDebug) {
	    printf("auto-focussing on %s, force %d\n", winPtr->pathName,
		    displayFocusPtr->forceFocus);
	}
	Tk_DeleteEventHandler((Tk_Window) winPtr, VisibilityChangeMask,
		FocusMapProc, clientData);
	displayFocusPtr->focusOnMapPtr = NULL;
	SetFocus(winPtr, displayFocusPtr->forceFocus);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * FindDisplayFocusInfo --
 *
 *	Given an application and a display, this procedure locate the
 *	focus record for that combination.  If no such record exists,
 *	it creates a new record and initializes it.
 *
 * Results:
 *	The return value is a pointer to the record.
 *
 * Side effects:
 *	A new record will be allocated if there wasn't one already.
 *
 *----------------------------------------------------------------------
 */

static DisplayFocusInfo *
FindDisplayFocusInfo(mainPtr, dispPtr)
    TkMainInfo *mainPtr;	/* Record that identifies a particular
				 * application. */
    TkDisplay *dispPtr;		/* Display whose focus information is
				 * needed. */
{
    DisplayFocusInfo *displayFocusPtr;

    for (displayFocusPtr = mainPtr->displayFocusPtr;
	    displayFocusPtr != NULL;
	    displayFocusPtr = displayFocusPtr->nextPtr) {
	if (displayFocusPtr->dispPtr == dispPtr) {
	    return displayFocusPtr;
	}
    }

    /*
     * The record doesn't exist yet.  Make a new one.
     */

    displayFocusPtr = (DisplayFocusInfo *) ckalloc(sizeof(DisplayFocusInfo));
    displayFocusPtr->dispPtr = dispPtr;
    displayFocusPtr->focusWinPtr = NULL;
    displayFocusPtr->focusOnMapPtr = NULL;
    displayFocusPtr->forceFocus = 0;
    displayFocusPtr->focusSerial = 0;
    displayFocusPtr->nextPtr = mainPtr->displayFocusPtr;
    mainPtr->displayFocusPtr = displayFocusPtr;
    return displayFocusPtr;
}