/*
* 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.
*/
#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 vArrowHeight, vThumb; /* Vertical control metrics. */
TCL_DECLARE_MUTEX(winScrlbrMutex)
/*
* Declarations for functions defined in this file.
*/
static Window CreateProc(Tk_Window tkwin, Window parent,
ClientData instanceData);
static void ModalLoop(WinScrollbar *, XEvent *eventPtr);
static LRESULT CALLBACK ScrollbarProc(HWND hwnd, UINT message, WPARAM wParam,
LPARAM lParam);
static void UpdateScrollbar(WinScrollbar *scrollPtr);
static void UpdateScrollbarMetrics(void);
/*
* The class procedure table for the scrollbar widget.
*/
const Tk_ClassProcs tkpScrollbarProcs = {
sizeof(Tk_ClassProcs), /* size */
NULL, /* worldChangedProc */
CreateProc, /* createProc */
NULL /* modalProc */
};
static void
WinScrollbarEventProc(ClientData clientData, XEvent *eventPtr)
{
WinScrollbar *scrollPtr = clientData;
if (eventPtr->type == ButtonPress) {
ModalLoop(scrollPtr, eventPtr);
} else {
TkScrollbarEventProc(clientData, eventPtr);
}
}
/*
*----------------------------------------------------------------------
*
* TkpCreateScrollbar --
*
* Allocate a new TkScrollbar structure.
*
* Results:
* Returns a newly allocated TkScrollbar structure.
*
* Side effects:
* Registers an event handler for the widget.
*
*----------------------------------------------------------------------
*/
TkScrollbar *
TkpCreateScrollbar(
Tk_Window tkwin)
{
WinScrollbar *scrollPtr;
if (!initialized) {
Tcl_MutexLock(&winScrlbrMutex);
UpdateScrollbarMetrics();
initialized = 1;
Tcl_MutexUnlock(&winScrlbrMutex);
}
scrollPtr = ckalloc(sizeof(WinScrollbar));
scrollPtr->winFlags = 0;
scrollPtr->hwnd = NULL;
Tk_CreateEventHandler(tkwin,
ExposureMask|StructureNotifyMask|FocusChangeMask|ButtonPressMask,
WinScrollbarEventProc, scrollPtr);
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(
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);
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;
/*
* Disable the scrollbar when there is nothing to scroll. This is
* standard Windows style (see eg Notepad). Also prevents possible
* crash on XP+ systems [Bug #624116].
*/
scrollInfo.fMask |= SIF_DISABLENOSCROLL;
}
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(
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(TEXT("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_HIERARCHY)) {
TkWinSetWindowPos(scrollPtr->hwnd, Tk_GetHWND(winPtr->window),
Below);
break;
}
}
scrollPtr->lastVertical = scrollPtr->info.vertical;
scrollPtr->oldProc = (WNDPROC)SetWindowLongPtr(scrollPtr->hwnd,
GWLP_WNDPROC, (LONG_PTR) 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) /* 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));
SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR) 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(
TkScrollbar *scrollPtr)
{
WinScrollbar *winScrollPtr = (WinScrollbar *)scrollPtr;
HWND hwnd = winScrollPtr->hwnd;
if (hwnd) {
SetWindowLongPtr(hwnd, GWLP_WNDPROC, (INT_PTR) 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(void)
{
int arrowWidth = GetSystemMetrics(SM_CXVSCROLL);
hArrowWidth = GetSystemMetrics(SM_CXHSCROLL);
hThumb = GetSystemMetrics(SM_CXHTHUMB);
vArrowHeight = GetSystemMetrics(SM_CYVSCROLL);
vThumb = GetSystemMetrics(SM_CYVTHUMB);
sprintf(tkDefScrollbarWidth, "%d", arrowWidth);
}
/*
*----------------------------------------------------------------------
*
* TkpComputeScrollbarGeometry --
*
* After changes in a scrollbar's size or configuration, this procedure
* recomputes various geometry information used in displaying the
* scrollbar.
*
* Results:
* None.
*
* Side effects:
* The scrollbar will be displayed differently.
*
*----------------------------------------------------------------------
*/
void
TkpComputeScrollbarGeometry(
register TkScrollbar *scrollPtr)
/* Scrollbar whose geometry may have
* changed. */
{
int fieldLength, minThumbSize;
/*
* Windows doesn't use focus rings on scrollbars, but we still perform
* basic sanity checks to appease backwards compatibility.
*/
if (scrollPtr->highlightWidth < 0) {
scrollPtr->highlightWidth = 0;
}
if (scrollPtr->vertical) {
scrollPtr->arrowLength = vArrowHeight;
fieldLength = Tk_Height(scrollPtr->tkwin);
minThumbSize = vThumb;
} else {
scrollPtr->arrowLength = hArrowWidth;
fieldLength = Tk_Width(scrollPtr->tkwin);
minThumbSize = hThumb;
}
fieldLength -= 2*scrollPtr->arrowLength;
if (fieldLength < 0) {
fieldLength = 0;
}
scrollPtr->sliderFirst = (int) ((double)fieldLength
* scrollPtr->firstFraction);
scrollPtr->sliderLast = (int) ((double)fieldLength
* scrollPtr->lastFraction);
/*
* Adjust the slider so that some piece of it is always displayed in the
* scrollbar and so that it has at least a minimal width (so it can be
* grabbed with the mouse).
*/
if (scrollPtr->sliderFirst > fieldLength) {
scrollPtr->sliderFirst = fieldLength;
}
if (scrollPtr->sliderFirst < 0) {
scrollPtr->sliderFirst = 0;
}
if (scrollPtr->sliderLast < (scrollPtr->sliderFirst
+ minThumbSize)) {
scrollPtr->sliderLast = scrollPtr->sliderFirst + minThumbSize;
}
if (scrollPtr->sliderLast > fieldLength) {
scrollPtr->sliderLast = fieldLength;
}
scrollPtr->sliderFirst += scrollPtr->arrowLength;
scrollPtr->sliderLast += scrollPtr->arrowLength;
/*
* Register the desired geometry for the window (leave enough space for
* the two arrows plus a minimum-size slider, plus border around the whole
* window, if any). Then arrange for the window to be redisplayed.
*/
if (scrollPtr->vertical) {
Tk_GeometryRequest(scrollPtr->tkwin,
scrollPtr->width, 2*scrollPtr->arrowLength + minThumbSize);
} else {
Tk_GeometryRequest(scrollPtr->tkwin,
2*scrollPtr->arrowLength + minThumbSize, scrollPtr->width);
}
Tk_SetInternalBorder(scrollPtr->tkwin, 0);
}
/*
*----------------------------------------------------------------------
*
* ScrollbarProc --
*
* This function is call by Windows whenever an event occurs on a
* scrollbar control created by Tk.
*
* Results:
* Standard Windows return value.
*
* Side effects:
* May generate events.
*
*----------------------------------------------------------------------
*/
static LRESULT CALLBACK
ScrollbarProc(
HWND hwnd,
UINT message,
WPARAM wParam,
LPARAM lParam)
{
LRESULT result;
POINT point;
WinScrollbar *scrollPtr;
Tk_Window tkwin = Tk_HWNDToWindow(hwnd);
if (tkwin == NULL) {
Tcl_Panic("ScrollbarProc called on an invalid HWND");
}
scrollPtr = (WinScrollbar *)((TkWindow*)tkwin)->instanceData;
switch(message) {
case WM_HSCROLL:
case WM_VSCROLL: {
Tcl_Interp *interp;
Tcl_DString cmdString;
int command = LOWORD(wParam);
int code;
GetCursorPos(&point);
Tk_TranslateWinEvent(NULL, WM_MOUSEMOVE, 0,
MAKELPARAM(point.x, point.y), &result);
if (command == SB_ENDSCROLL) {
return 0;
}
/*
* Bail out immediately if there isn't a command to invoke.
*/
if (scrollPtr->info.commandSize == 0) {
Tcl_ServiceAll();
return 0;
}
Tcl_DStringInit(&cmdString);
Tcl_DStringAppend(&cmdString, scrollPtr->info.command,
scrollPtr->info.commandSize);
if (command == SB_LINELEFT || command == SB_LINERIGHT) {
Tcl_DStringAppendElement(&cmdString, "scroll");
Tcl_DStringAppendElement(&cmdString,
(command == SB_LINELEFT ) ? "-1" : "1");
Tcl_DStringAppendElement(&cmdString, "units");
} else if (command == SB_PAGELEFT || command == SB_PAGERIGHT) {
Tcl_DStringAppendElement(&cmdString, "scroll");
Tcl_DStringAppendElement(&cmdString,
(command == SB_PAGELEFT ) ? "-1" : "1");
Tcl_DStringAppendElement(&cmdString, "pages");
} else {
char valueString[TCL_DOUBLE_SPACE];
double pos = 0.0;
switch (command) {
case SB_THUMBPOSITION:
pos = ((double)HIWORD(wParam)) / MAX_SCROLL;
break;
case SB_THUMBTRACK:
pos = ((double)HIWORD(wParam)) / MAX_SCROLL;
break;
case SB_TOP:
pos = 0.0;
break;
case SB_BOTTOM:
pos = 1.0;
break;
}
Tcl_PrintDouble(NULL, pos, valueString);
Tcl_DStringAppendElement(&cmdString, "moveto");
Tcl_DStringAppendElement(&cmdString, valueString);
}
interp = scrollPtr->info.interp;
code = Tcl_GlobalEval(interp, cmdString.string);
if (code != TCL_OK && code != TCL_CONTINUE && code != TCL_BREAK) {
Tcl_AddErrorInfo(interp, "\n (scrollbar command)");
Tcl_BackgroundException(interp, code);
}
Tcl_DStringFree(&cmdString);
Tcl_ServiceAll();
return 0;
}
default:
if (Tk_TranslateWinEvent(hwnd, message, wParam, lParam, &result)) {
return result;
}
}
return CallWindowProc(scrollPtr->oldProc, hwnd, message, wParam, lParam);
}
/*
*----------------------------------------------------------------------
*
* TkpConfigureScrollbar --
*
* This procedure is called after the generic code has finished
* processing configuration options, in order to configure platform
* specific options.
*
* Results:
* None.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
void
TkpConfigureScrollbar(
register TkScrollbar *scrollPtr)
/* Information about widget; may or may not
* already have values for some fields. */
{
}
/*
*----------------------------------------------------------------------
*
* ModalLoop --
*
* This function is invoked in response to a ButtonPress event.
* It resends the event to the Scrollbar window procedure,
* which in turn enters a modal loop.
*
*----------------------------------------------------------------------
*/
static void
ModalLoop(
WinScrollbar *scrollPtr,
XEvent *eventPtr)
{
int oldMode;
if (scrollPtr->hwnd) {
Tcl_Preserve((ClientData)scrollPtr);
scrollPtr->winFlags |= IN_MODAL_LOOP;
oldMode = Tcl_SetServiceMode(TCL_SERVICE_ALL);
TkWinResendEvent(scrollPtr->oldProc, scrollPtr->hwnd, eventPtr);
(void) Tcl_SetServiceMode(oldMode);
scrollPtr->winFlags &= ~IN_MODAL_LOOP;
if (scrollPtr->hwnd && scrollPtr->winFlags & ALREADY_DEAD) {
DestroyWindow(scrollPtr->hwnd);
}
Tcl_Release((ClientData)scrollPtr);
}
}
/*
*--------------------------------------------------------------
*
* TkpScrollbarPosition --
*
* Determine the scrollbar element corresponding to a given position.
*
* Results:
* One of TOP_ARROW, TOP_GAP, etc., indicating which element of the
* scrollbar covers the position given by (x, y). If (x,y) is outside the
* scrollbar entirely, then OUTSIDE is returned.
*
* Side effects:
* None.
*
*--------------------------------------------------------------
*/
int
TkpScrollbarPosition(
register TkScrollbar *scrollPtr,
/* Scrollbar widget record. */
int x, int y) /* Coordinates within scrollPtr's window. */
{
int length, width, tmp;
if (scrollPtr->vertical) {
length = Tk_Height(scrollPtr->tkwin);
width = Tk_Width(scrollPtr->tkwin);
} else {
tmp = x;
x = y;
y = tmp;
length = Tk_Width(scrollPtr->tkwin);
width = Tk_Height(scrollPtr->tkwin);
}
if ((x < scrollPtr->inset) || (x >= (width - scrollPtr->inset))
|| (y < scrollPtr->inset) || (y >= (length - scrollPtr->inset))) {
return OUTSIDE;
}
/*
* All of the calculations in this procedure mirror those in
* TkpDisplayScrollbar. Be sure to keep the two consistent.
*/
if (y < (scrollPtr->inset + scrollPtr->arrowLength)) {
return TOP_ARROW;
}
if (y < scrollPtr->sliderFirst) {
return TOP_GAP;
}
if (y < scrollPtr->sliderLast) {
return SLIDER;
}
if (y >= (length - (scrollPtr->arrowLength + scrollPtr->inset))) {
return BOTTOM_ARROW;
}
return BOTTOM_GAP;
}
/*
* Local Variables:
* mode: c
* c-basic-offset: 4
* fill-column: 78
* End:
*/