tkwinscrlbr.c

linux系统下的音频通信

/* 
 * tkWinScrollbar.c --
 *
 *	This file implements the Windows specific portion of the scrollbar
 *	widget.
 *
 * Copyright (c) 1996 by Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * SCCS: @(#) tkWinScrlbr.c 1.19 97/08/13 17:37:49
 */

#include "tkWinInt.h"
#include "tkScrollbar.h"


/*
 * The following constant is used to specify the maximum scroll position.
 * This value is limited by the Win32 API to either 16-bits or 32-bits,
 * depending on the context.  For now we'll just use a value small
 * enough to fit in 16-bits, but which gives us 4-digits of precision.
 */

#define MAX_SCROLL 10000

/*
 * Declaration of Windows specific scrollbar structure.
 */

typedef struct WinScrollbar {
    TkScrollbar info;		/* Generic scrollbar info. */
    WNDPROC oldProc;		/* Old window procedure. */
    int lastVertical;		/* 1 if was vertical at last refresh. */
    HWND hwnd;			/* Current window handle. */
    int winFlags;		/* Various flags; see below. */
} WinScrollbar;

/*
 * Flag bits for native scrollbars:
 * 
 * IN_MODAL_LOOP:		Non-zero means this scrollbar is in the middle
 *				of a modal loop.
 * ALREADY_DEAD:		Non-zero means this scrollbar has been
 *				destroyed, but has not been cleaned up.
 */

#define IN_MODAL_LOOP	1
#define ALREADY_DEAD	2

/*
 * Cached system metrics used to determine scrollbar geometry.
 */

static int initialized = 0;
static int hArrowWidth, hThumb; /* Horizontal control metrics. */
static int vArrowWidth, vArrowHeight, vThumb; /* Vertical control metrics. */

/*
 * This variable holds the default width for a scrollbar in string
 * form for use in a Tk_ConfigSpec.
 */

static char defWidth[8];

/*
 * Declarations for functions defined in this file.
 */

static Window		CreateProc _ANSI_ARGS_((Tk_Window tkwin,
			    Window parent, ClientData instanceData));
static void		ModalLoopProc _ANSI_ARGS_((Tk_Window tkwin,
			    XEvent *eventPtr));
static int		ScrollbarBindProc _ANSI_ARGS_((ClientData clientData,
			    Tcl_Interp *interp, XEvent *eventPtr,
			    Tk_Window tkwin, KeySym keySym));
static LRESULT CALLBACK	ScrollbarProc _ANSI_ARGS_((HWND hwnd, UINT message,
			    WPARAM wParam, LPARAM lParam));
static void		UpdateScrollbar _ANSI_ARGS_((
    			    WinScrollbar *scrollPtr));
static void		UpdateScrollbarMetrics _ANSI_ARGS_((void));

/*
 * The class procedure table for the scrollbar widget.
 */

TkClassProcs tkpScrollbarProcs = {
    CreateProc,			/* createProc */
    NULL,			/* geometryProc */
    ModalLoopProc,		/* modalProc */
};


/*
 *----------------------------------------------------------------------
 *
 * TkpCreateScrollbar --
 *
 *	Allocate a new TkScrollbar structure.
 *
 * Results:
 *	Returns a newly allocated TkScrollbar structure.
 *
 * Side effects:
 *	Registers an event handler for the widget.
 *
 *----------------------------------------------------------------------
 */

TkScrollbar *
TkpCreateScrollbar(tkwin)
    Tk_Window tkwin;
{
    WinScrollbar *scrollPtr;
    TkWindow *winPtr = (TkWindow *)tkwin;
    
    if (!initialized) {
	UpdateScrollbarMetrics();
	initialized = 1;
    }

    scrollPtr = (WinScrollbar *) ckalloc(sizeof(WinScrollbar));
    scrollPtr->winFlags = 0;
    scrollPtr->hwnd = NULL;

    Tk_CreateEventHandler(tkwin,
	    ExposureMask|StructureNotifyMask|FocusChangeMask,
	    TkScrollbarEventProc, (ClientData) scrollPtr);

    if (!Tcl_GetAssocData(winPtr->mainPtr->interp, "TkScrollbar", NULL)) {
	Tcl_SetAssocData(winPtr->mainPtr->interp, "TkScrollbar", NULL,
		(ClientData)1);
	TkCreateBindingProcedure(winPtr->mainPtr->interp,
		winPtr->mainPtr->bindingTable,
		(ClientData)Tk_GetUid("Scrollbar"), "<ButtonPress>",
		ScrollbarBindProc, NULL, NULL);
    }

    return (TkScrollbar*) scrollPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * UpdateScrollbar --
 *
 *	This function updates the position and size of the scrollbar
 *	thumb based on the current settings.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Moves the thumb.
 *
 *----------------------------------------------------------------------
 */

static void
UpdateScrollbar(scrollPtr)
    WinScrollbar *scrollPtr;
{
    SCROLLINFO scrollInfo;
    double thumbSize;

    /*
     * Update the current scrollbar position and shape.
     */

    scrollInfo.fMask = SIF_PAGE | SIF_POS | SIF_RANGE;
    scrollInfo.cbSize = sizeof(scrollInfo);
    scrollInfo.nMin = 0;
    scrollInfo.nMax = MAX_SCROLL;
    thumbSize = (scrollPtr->info.lastFraction - scrollPtr->info.firstFraction);
    if (tkpIsWin32s) {
	scrollInfo.nPage = 0;
    } else {
	scrollInfo.nPage = ((UINT) (thumbSize * (double) MAX_SCROLL)) + 1;
    } 
    if (thumbSize < 1.0) {
	scrollInfo.nPos = (int)
	    ((scrollPtr->info.firstFraction / (1.0-thumbSize))
		    * (MAX_SCROLL - (scrollInfo.nPage - 1)));
    } else {
	scrollInfo.nPos = 0;
    }
    SetScrollInfo(scrollPtr->hwnd, SB_CTL, &scrollInfo, TRUE);
}

/*
 *----------------------------------------------------------------------
 *
 * CreateProc --
 *
 *	This function creates a new Scrollbar control, subclasses
 *	the instance, and generates a new Window object.
 *
 * Results:
 *	Returns the newly allocated Window object, or None on failure.
 *
 * Side effects:
 *	Causes a new Scrollbar control to come into existence.
 *
 *----------------------------------------------------------------------
 */

static Window
CreateProc(tkwin, parentWin, instanceData)
    Tk_Window tkwin;		/* Token for window. */
    Window parentWin;		/* Parent of new window. */
    ClientData instanceData;	/* Scrollbar instance data. */
{
    DWORD style;
    Window window;
    HWND parent;
    TkWindow *winPtr;
    WinScrollbar *scrollPtr = (WinScrollbar *)instanceData;

    parent = Tk_GetHWND(parentWin);

    if (scrollPtr->info.vertical) {
	style = WS_CHILD | WS_VISIBLE | WS_CLIPCHILDREN | WS_CLIPSIBLINGS
	    | SBS_VERT | SBS_RIGHTALIGN;
    } else {
	style = WS_CHILD | WS_VISIBLE | WS_CLIPCHILDREN | WS_CLIPSIBLINGS
	    | SBS_HORZ | SBS_BOTTOMALIGN;
    }

    scrollPtr->hwnd = CreateWindow("SCROLLBAR", NULL, style,
	    Tk_X(tkwin), Tk_Y(tkwin), Tk_Width(tkwin), Tk_Height(tkwin),
	    parent, NULL, Tk_GetHINSTANCE(), NULL);

    /*
     * Ensure new window is inserted into the stacking order at the correct
     * place. 
     */

    SetWindowPos(scrollPtr->hwnd, HWND_TOP, 0, 0, 0, 0,
		    SWP_NOACTIVATE | SWP_NOMOVE | SWP_NOSIZE);

    for (winPtr = ((TkWindow*)tkwin)->nextPtr; winPtr != NULL;
	 winPtr = winPtr->nextPtr) {
	if ((winPtr->window != None) && !(winPtr->flags & TK_TOP_LEVEL)) {
	    TkWinSetWindowPos(scrollPtr->hwnd, Tk_GetHWND(winPtr->window),
		    Below);
	    break;
	}
    }

    scrollPtr->lastVertical = scrollPtr->info.vertical;
    scrollPtr->oldProc = (WNDPROC)SetWindowLong(scrollPtr->hwnd, GWL_WNDPROC,
	    (DWORD) ScrollbarProc);
    window = Tk_AttachHWND(tkwin, scrollPtr->hwnd);

    UpdateScrollbar(scrollPtr);
    return window;
}

/*
 *--------------------------------------------------------------
 *
 * TkpDisplayScrollbar --
 *
 *	This procedure redraws the contents of a scrollbar window.
 *	It is invoked as a do-when-idle handler, so it only runs
 *	when there's nothing else for the application to do.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Information appears on the screen.
 *
 *--------------------------------------------------------------
 */

void
TkpDisplayScrollbar(clientData)
    ClientData clientData;	/* Information about window. */
{
    WinScrollbar *scrollPtr = (WinScrollbar *) clientData;
    Tk_Window tkwin = scrollPtr->info.tkwin;

    scrollPtr->info.flags &= ~REDRAW_PENDING;
    if ((tkwin == NULL) || !Tk_IsMapped(tkwin)) {
	return;
    }

    /*
     * Destroy and recreate the scrollbar control if the orientation
     * has changed.
     */

    if (scrollPtr->lastVertical != scrollPtr->info.vertical) {
	HWND hwnd = Tk_GetHWND(Tk_WindowId(tkwin));

	SetWindowLong(hwnd, GWL_WNDPROC, (DWORD) scrollPtr->oldProc);
	DestroyWindow(hwnd);

	CreateProc(tkwin, Tk_WindowId(Tk_Parent(tkwin)),
		(ClientData) scrollPtr);
    } else {
	UpdateScrollbar(scrollPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkpDestroyScrollbar --
 *
 *	Free data structures associated with the scrollbar control.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Restores the default control state.
 *
 *----------------------------------------------------------------------
 */

void
TkpDestroyScrollbar(scrollPtr)
    TkScrollbar *scrollPtr;
{
    WinScrollbar *winScrollPtr = (WinScrollbar *)scrollPtr;
    HWND hwnd = winScrollPtr->hwnd;
    if (hwnd) {
	SetWindowLong(hwnd, GWL_WNDPROC, (DWORD) winScrollPtr->oldProc);
	if (winScrollPtr->winFlags & IN_MODAL_LOOP) {
	    ((TkWindow *)scrollPtr->tkwin)->flags |= TK_DONT_DESTROY_WINDOW;
	    SetParent(hwnd, NULL);
	}
    }
    winScrollPtr->winFlags |= ALREADY_DEAD;
}

/*
 *----------------------------------------------------------------------
 *
 * UpdateScrollbarMetrics --
 *
 *	This function retrieves the current system metrics for a
 *	scrollbar.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Updates the geometry cache info for all scrollbars.
 *
 *----------------------------------------------------------------------
 */

void
UpdateScrollbarMetrics()
{
    Tk_ConfigSpec *specPtr;

    hArrowWidth = GetSystemMetrics(SM_CXHSCROLL);
    hThumb = GetSystemMetrics(SM_CXHTHUMB);
    vArrowWidth = GetSystemMetrics(SM_CXVSCROLL);
    vArrowHeight = GetSystemMetrics(SM_CYVSCROLL);
    vThumb = GetSystemMetrics(SM_CYVTHUMB);

    sprintf(defWidth, "%d", vArrowWidth);
    for (specPtr = tkpScrollbarConfigSpecs; specPtr->type != TK_CONFIG_END;
	    specPtr++) {
	if (specPtr->offset == Tk_Offset(TkScrollbar, width)) {
	    specPtr->defValue = defWidth;
	}