Changelog:
scrollbar.c - removes SCROLL_ShowScrollBar SCROLL_SetScrollInfo
- breaks SCROLL_GetScrollInfo into two functions
- significantly simplifies SetScrollInfo
- simplifies other api functions
This interim patch will do a little more drawing than is strictly necessary
The patch was developed without CVS access use patch -p1 from within
the top level wine directory to apply
License: X11
Andrew
--- wine-20021007/controls/scroll.c Thu Oct 10 16:47:37 2002
+++ wine/controls/scroll.c Thu Oct 10 19:06:17 2002
@@ -37,7 +37,7 @@
INT maxVal; /* Maximum scroll-bar value */
INT page; /* Page size of scroll bar (Win32) */
UINT flags; /* EnableScrollBar flags */
-} SCROLLBAR_INFO;
+} SCROLLBAR_INFO, *LPSCROLLBAR_INFO;
static HBITMAP hUpArrow;
@@ -81,6 +81,12 @@
/* Scroll timer id */
#define SCROLL_TIMER 0
+/* Determine if the info is valid */
+#define SCROLL_INFO_INVALID(info) \
+ ((info->fMask & ~(SIF_ALL | SIF_DISABLENOSCROLL)) || \
+ ((info->cbSize != sizeof(*info)) && \
+ (info->cbSize != sizeof(*info) - sizeof(info->nTrackPos))))
+
/* Scroll-bar hit testing */
enum SCROLL_HITTEST
{
@@ -111,10 +117,6 @@
static BOOL SCROLL_MovingThumb = FALSE;
/* Local functions */
-static BOOL SCROLL_ShowScrollBar( HWND hwnd, INT nBar,
- BOOL fShowH, BOOL fShowV );
-static INT SCROLL_SetScrollInfo( HWND hwnd, INT nBar,
- const SCROLLINFO *info, INT *action );
static void SCROLL_DrawInterior_9x( HWND hwnd, HDC hdc, INT nBar,
RECT *rect, INT arrowSize,
INT thumbSize, INT thumbPos,
@@ -1408,6 +1410,7 @@
/*************************************************************************
* SetScrollInfo (USER32.@)
+ *
* SetScrollInfo can be used to set the position, upper bound,
* lower bound, and page size of a scrollbar control.
*
@@ -1416,166 +1419,111 @@
*
* NOTE
* For 100 lines of text to be displayed in a window of 25 lines,
- * one would for instance use info->nMin=0, info->nMax=75
+ * one would for instance use info->nMin = 0, info->nMax = 75
* (corresponding to the 76 different positions of the window on
- * the text), and info->nPage=25.
+ * the text), and info->nPage = 25.
*/
-INT WINAPI SetScrollInfo(
-HWND hwnd /* [in] Handle of window whose scrollbar will be affected */,
-INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
+INT WINAPI SetScrollInfo(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
const SCROLLINFO *info /* [in] Specifies what to change and new values */,
BOOL bRedraw /* [in] Should scrollbar be redrawn afterwards ? */)
{
- INT action;
- INT retVal = SCROLL_SetScrollInfo( hwnd, nBar, info, &action );
-
- if( action & SA_SSI_HIDE )
- SCROLL_ShowScrollBar( hwnd, nBar, FALSE, FALSE );
- else
- {
- if( action & SA_SSI_SHOW )
- if( SCROLL_ShowScrollBar( hwnd, nBar, TRUE, TRUE ) )
- return retVal; /* SetWindowPos() already did the painting */
-
- if( bRedraw && (action & SA_SSI_REFRESH))
- SCROLL_RefreshScrollBar( hwnd, nBar, TRUE, TRUE );
- else if( action & SA_SSI_REPAINT_ARROWS )
- SCROLL_RefreshScrollBar( hwnd, nBar, TRUE, FALSE );
- }
- return retVal;
-}
-
-INT SCROLL_SetScrollInfo( HWND hwnd, INT nBar,
- const SCROLLINFO *info, INT *action )
-{
- /* Update the scrollbar state and set action flags according to
- * what has to be done graphics wise. */
-
- SCROLLBAR_INFO *infoPtr;
- UINT new_flags;
- BOOL bChangeParams = FALSE; /* don't show/hide scrollbar if params don't
change */
-
- *action = 0;
-
- if (!(infoPtr = SCROLL_GetScrollInfo(hwnd, nBar))) return 0;
- if (info->fMask & ~(SIF_ALL | SIF_DISABLENOSCROLL)) return 0;
- if ((info->cbSize != sizeof(*info)) &&
- (info->cbSize != sizeof(*info)-sizeof(info->nTrackPos))) return 0;
+ LPSCROLLBAR_INFO infoPtr;
+ BOOL changed = FALSE; /* only show/hide scrollbar if params change */
+ INT gap, value;
+ UINT oldFlags;
+
+ /* handle invalid data structure */
+ if (SCROLL_INFO_INVALID(info)) return 0;
+ infoPtr = SCROLL_GetScrollInfo(hwnd, nBar);
+ if (!infoPtr) return 0;
if (TRACE_ON(scroll))
{
TRACE("hwnd=%04x bar=%d", hwnd, nBar);
- if (info->fMask & SIF_PAGE) DPRINTF( " page=%d", info->nPage );
- if (info->fMask & SIF_POS) DPRINTF( " pos=%d", info->nPos );
- if (info->fMask & SIF_RANGE) DPRINTF( " min=%d max=%d", info->nMin,
info->nMax );
- DPRINTF("\n");
+ if (info->fMask & SIF_PAGE) DPRINTF(" page=%d", info->nPage);
+ if (info->fMask & SIF_POS) DPRINTF(" pos=%d", info->nPos);
+ if (info->fMask & SIF_RANGE)
+ DPRINTF(" min=%d max=%d", info->nMin, info->nMax);
+ DPRINTF(" bRedraw=%d\n", bRedraw);
}
- /* Set the page size */
-
- if (info->fMask & SIF_PAGE)
- {
- if( infoPtr->page != info->nPage )
- {
- infoPtr->page = info->nPage;
- *action |= SA_SSI_REFRESH;
- bChangeParams = TRUE;
- }
- }
-
- /* Set the scroll pos */
-
- if (info->fMask & SIF_POS)
- {
- if( infoPtr->curVal != info->nPos )
- {
- infoPtr->curVal = info->nPos;
- *action |= SA_SSI_REFRESH;
- }
- }
-
- /* Set the scroll range */
-
+ /* set the scroll range */
if (info->fMask & SIF_RANGE)
{
- /* Invalid range -> range is set to (0,0) */
if ((info->nMin > info->nMax) ||
((UINT)(info->nMax - info->nMin) >= 0x80000000))
{
+ /* invalid range -> range is set to (0,0) */
+ changed = ((infoPtr->minVal) || (infoPtr->maxVal));
infoPtr->minVal = 0;
infoPtr->maxVal = 0;
- bChangeParams = TRUE;
}
- else
+ else if ((infoPtr->minVal != info->nMin) ||
+ (infoPtr->maxVal != info->nMax))
{
- if( infoPtr->minVal != info->nMin ||
- infoPtr->maxVal != info->nMax )
- {
- *action |= SA_SSI_REFRESH;
- infoPtr->minVal = info->nMin;
- infoPtr->maxVal = info->nMax;
- bChangeParams = TRUE;
- }
+ infoPtr->minVal = info->nMin;
+ infoPtr->maxVal = info->nMax;
+ changed = TRUE;
}
}
- /* Make sure the page size is valid */
-
- if (infoPtr->page < 0) infoPtr->page = 0;
- else if (infoPtr->page > infoPtr->maxVal - infoPtr->minVal + 1 )
- infoPtr->page = infoPtr->maxVal - infoPtr->minVal + 1;
-
- /* Make sure the pos is inside the range */
-
- if (infoPtr->curVal < infoPtr->minVal)
- infoPtr->curVal = infoPtr->minVal;
- else if (infoPtr->curVal > infoPtr->maxVal - max( infoPtr->page-1, 0 ))
- infoPtr->curVal = infoPtr->maxVal - max( infoPtr->page-1, 0 );
+ /* determine desired page size */
+ value = infoPtr->page;
+ if ((info->fMask & SIF_PAGE) && (value != info->nPage))
+ value = info->nPage;
+
+ /* make sure the page size is valid */
+ gap = infoPtr->maxVal - infoPtr->minVal + 1;
+ if (value > gap)
+ value = gap;
+ else if (value < 1)
+ value = 1;
+ /* change page if required */
+ if (value != infoPtr->page)
+ {
+ infoPtr->page = value;
+ changed = TRUE;
+ }
+
+ /* set the scroll pos */
+ value = infoPtr->curVal;
+ if ((info->fMask & SIF_POS) && (value != info->nPos))
+ value = info->nPos;
+
+ /* make sure the pos is inside the range */
+ gap = infoPtr->maxVal - infoPtr->page + 1;
+ if (value < infoPtr->minVal)
+ value = infoPtr->minVal;
+ else if (value > gap)
+ value = gap;
TRACE(" new values: page=%d pos=%d min=%d max=%d\n",
- infoPtr->page, infoPtr->curVal,
- infoPtr->minVal, infoPtr->maxVal );
+ infoPtr->page, value, infoPtr->minVal, infoPtr->maxVal);
- /* don't change the scrollbar state if SetScrollInfo
- * is just called with SIF_DISABLENOSCROLL
- */
- if(!(info->fMask & SIF_ALL)) goto done;
-
- /* Check if the scrollbar should be hidden or disabled */
-
- if (info->fMask & (SIF_RANGE | SIF_PAGE | SIF_DISABLENOSCROLL))
- {
- new_flags = infoPtr->flags;
- if (infoPtr->minVal >= infoPtr->maxVal - max( infoPtr->page-1, 0 ))
- {
- /* Hide or disable scroll-bar */
- if (info->fMask & SIF_DISABLENOSCROLL)
- {
- new_flags = ESB_DISABLE_BOTH;
- *action |= SA_SSI_REFRESH;
- }
- else if ((nBar != SB_CTL) && bChangeParams)
- {
- *action = SA_SSI_HIDE;
- goto done;
- }
- }
- else /* Show and enable scroll-bar */
- {
- new_flags = 0;
- if ((nBar != SB_CTL) && bChangeParams)
- *action |= SA_SSI_SHOW;
- }
-
- if (infoPtr->flags != new_flags) /* check arrow flags */
- {
- infoPtr->flags = new_flags;
- *action |= SA_SSI_REPAINT_ARROWS;
- }
- }
-
-done:
- /* Return current position */
+ /* determine the activation state */
+ oldFlags = infoPtr->flags;
+ if (!(info->fMask & SIF_ALL))
+ ; /* if called without SIF_ALL don't change state */
+ else if (info->fMask & SIF_DISABLENOSCROLL)
+ infoPtr->flags |= ESB_DISABLE_BOTH;
+ else if (changed && (nBar != SB_CTL) &&
+ (info->fMask & (SIF_RANGE | SIF_PAGE)))
+ ShowScrollBar(hwnd, nBar, infoPtr->minVal < gap);
+
+ /* change position if required */
+ if (value != infoPtr->curVal)
+ {
+ infoPtr->curVal = value;
+ changed = TRUE;
+ }
+
+ /* redraw the scroll bar if desired or required */
+ if (WIN_IsWindowDrawable(hwnd, FALSE) &&
+ ((infoPtr->flags != oldFlags) ||
+ (bRedraw && changed && (infoPtr->minVal < gap))))
+ SCROLL_RefreshScrollBar(hwnd, nBar, TRUE, TRUE);
return infoPtr->curVal;
}
@@ -1583,33 +1531,38 @@
/*************************************************************************
* GetScrollInfo (USER32.@)
- * GetScrollInfo can be used to retrieve the position, upper bound,
+ *
+ * GetScrollInfo can be used to retrieve the position, upper bound,
* lower bound, and page size of a scrollbar control.
*
* RETURNS STD
*/
-BOOL WINAPI GetScrollInfo(
- HWND hwnd /* [in] Handle of window */ ,
- INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
- LPSCROLLINFO info /* [in/out] (info.fMask [in] specifies which values are
to retrieve) */)
+BOOL WINAPI GetScrollInfo(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
+LPSCROLLINFO info /* [in/out] (fMask specifies which values to retrieve) */)
{
- SCROLLBAR_INFO *infoPtr;
+ LPSCROLLBAR_INFO infoPtr;
+
+ /* handle invalid data structure */
+ if (SCROLL_INFO_INVALID(info)) return FALSE;
+ infoPtr = SCROLL_GetScrollInfo(hwnd, nBar);
+ if (!infoPtr) return FALSE;
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, nBar ))) return FALSE;
- if (info->fMask & ~(SIF_ALL | SIF_DISABLENOSCROLL)) return FALSE;
- if ((info->cbSize != sizeof(*info)) &&
- (info->cbSize != sizeof(*info)-sizeof(info->nTrackPos))) return
FALSE;
+ TRACE("hwnd=%04x nBar=%d info=%p\n", hwnd, nBar, info);
+ /* fill in the desired scroll info structure */
if (info->fMask & SIF_PAGE) info->nPage = infoPtr->page;
if (info->fMask & SIF_POS) info->nPos = infoPtr->curVal;
if ((info->fMask & SIF_TRACKPOS) && (info->cbSize == sizeof(*info)))
info->nTrackPos = (SCROLL_TrackingWin == WIN_GetFullHandle(hwnd)) ?
SCROLL_TrackingVal : infoPtr->curVal;
if (info->fMask & SIF_RANGE)
{
- info->nMin = infoPtr->minVal;
- info->nMax = infoPtr->maxVal;
+ info->nMin = infoPtr->minVal;
+ info->nMax = infoPtr->maxVal;
}
- return (info->fMask & SIF_ALL) != 0;
+
+ return (info->fMask & SIF_ALL);
}
@@ -1624,23 +1577,25 @@
* Note the ambiguity when 0 is returned. Use GetLastError
* to make sure there was an error (and to know which one).
*/
-INT WINAPI SetScrollPos(
-HWND hwnd /* [in] Handle of window whose scrollbar will be affected */,
+INT WINAPI SetScrollPos(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
INT nPos /* [in] New value */,
-BOOL bRedraw /* [in] Should scrollbar be redrawn afterwards ? */ )
+BOOL bRedraw /* [in] Should scrollbar be redrawn afterwards ? */)
{
+ INT oldPos = GetScrollPos(hwnd, nBar);
SCROLLINFO info;
- SCROLLBAR_INFO *infoPtr;
- INT oldPos;
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, nBar ))) return 0;
- oldPos = infoPtr->curVal;
+ TRACE("hwnd=%04x nBar=%d nPos=%d bRedraw=%d\n",
+ hwnd, nBar, nPos, bRedraw);
+
+ /* fill in an info structure and use common set info code */
info.cbSize = sizeof(info);
info.nPos = nPos;
info.fMask = SIF_POS;
- SetScrollInfo( hwnd, nBar, &info, bRedraw );
- return oldPos;
+ SetScrollInfo(hwnd, nBar, &info, bRedraw);
+
+ return oldPos;
}
@@ -1649,20 +1604,21 @@
*
* RETURNS
* Success: Current position
- * Failure: 0
+ * Failure: 0
*
* REMARKS
- * Note the ambiguity when 0 is returned. Use GetLastError
+ * There is ambiguity when 0 is returned. Use GetLastError
* to make sure there was an error (and to know which one).
*/
-INT WINAPI GetScrollPos(
-HWND hwnd, /* [in] Handle of window */
+INT WINAPI GetScrollPos(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */)
{
- SCROLLBAR_INFO *infoPtr;
+ LPSCROLLBAR_INFO info = SCROLL_GetScrollInfo(hwnd, nBar);
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, nBar ))) return 0;
- return infoPtr->curVal;
+ TRACE("hwnd=%04x nBar=%d\n", hwnd, nBar);
+
+ return info ? info->curVal: 0;
}
@@ -1671,58 +1627,26 @@
*
* RETURNS STD
*/
-BOOL WINAPI SetScrollRange(
-HWND hwnd, /* [in] Handle of window whose scrollbar will be affected */
-INT nBar, /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */
-INT minVal, /* [in] New minimum value */
-INT maxVal, /* [in] New maximum value */
+BOOL WINAPI SetScrollRange(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
+INT minVal /* [in] New minimum value */,
+INT maxVal /* [in] New maximum value */,
BOOL bRedraw /* [in] Should scrollbar be redrawn afterwards ? */)
{
SCROLLINFO info;
+ TRACE("hwnd=%04x nBar=%d minVal=%d maxVal=%d bRedraw=%d\n",
+ hwnd, nBar, minVal, maxVal, bRedraw);
+
+ /* fill in an info structure and use common set info code */
info.cbSize = sizeof(info);
info.nMin = minVal;
info.nMax = maxVal;
info.fMask = SIF_RANGE;
- SetScrollInfo( hwnd, nBar, &info, bRedraw );
- return TRUE;
-}
-
-
-/*************************************************************************
- * SCROLL_SetNCSbState
- *
- * Updates both scrollbars at the same time. Used by MDI CalcChildScroll().
- */
-INT SCROLL_SetNCSbState(HWND hwnd, int vMin, int vMax, int vPos,
- int hMin, int hMax, int hPos)
-{
- INT vA, hA;
- SCROLLINFO vInfo, hInfo;
-
- vInfo.cbSize = hInfo.cbSize = sizeof(SCROLLINFO);
- vInfo.nMin = vMin;
- vInfo.nMax = vMax;
- vInfo.nPos = vPos;
- hInfo.nMin = hMin;
- hInfo.nMax = hMax;
- hInfo.nPos = hPos;
- vInfo.fMask = hInfo.fMask = SIF_RANGE | SIF_POS;
+ SetScrollInfo(hwnd, nBar, &info, bRedraw);
- SCROLL_SetScrollInfo( hwnd, SB_VERT, &vInfo, &vA );
- SCROLL_SetScrollInfo( hwnd, SB_HORZ, &hInfo, &hA );
-
- if( !SCROLL_ShowScrollBar( hwnd, SB_BOTH,
- (hA & SA_SSI_SHOW),(vA & SA_SSI_SHOW) ) )
- {
- /* SetWindowPos() wasn't called, just redraw the scrollbars if needed */
- if( vA & SA_SSI_REFRESH )
- SCROLL_RefreshScrollBar( hwnd, SB_VERT, FALSE, TRUE );
-
- if( hA & SA_SSI_REFRESH )
- SCROLL_RefreshScrollBar( hwnd, SB_HORZ, FALSE, TRUE );
- }
- return 0;
+ return TRUE;
}
@@ -1731,138 +1655,105 @@
*
* RETURNS STD
*/
-BOOL WINAPI GetScrollRange(
-HWND hwnd, /* [in] Handle of window */
-INT nBar, /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */
-LPINT lpMin, /* [out] Where to store minimum value */
+BOOL WINAPI GetScrollRange(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, or SB_CTL */,
+LPINT lpMin /* [out] Where to store minimum value */,
LPINT lpMax /* [out] Where to store maximum value */)
{
- SCROLLBAR_INFO *infoPtr;
+ LPSCROLLBAR_INFO info = SCROLL_GetScrollInfo(hwnd, nBar);
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, nBar )))
- {
- if (lpMin) lpMin = 0;
- if (lpMax) lpMax = 0;
- return FALSE;
- }
- if (lpMin) *lpMin = infoPtr->minVal;
- if (lpMax) *lpMax = infoPtr->maxVal;
- return TRUE;
+ TRACE("hwnd=%04x nBar=%d lpMin=%p lpMax=%p\n", hwnd, nBar, lpMin, lpMax);
+
+ if (lpMin) *lpMin = info ? info->minVal : 0;
+ if (lpMax) *lpMax = info ? info->maxVal : 0;
+
+ return (BOOL)info;
}
/*************************************************************************
- * SCROLL_ShowScrollBar()
+ * ShowScrollBar (USER32.@)
*
- * Back-end for ShowScrollBar(). Returns FALSE if no action was taken.
+ * RETURNS STD
*/
-BOOL SCROLL_ShowScrollBar( HWND hwnd, INT nBar,
- BOOL fShowH, BOOL fShowV )
+BOOL WINAPI ShowScrollBar(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, SB_BOTH or SB_CTL */,
+BOOL fShow /* [in] TRUE = show, FALSE = hide */)
{
LONG style = GetWindowLongW( hwnd, GWL_STYLE );
+ LONG oldStyle = style;
- TRACE("hwnd=%04x bar=%d horz=%d, vert=%d\n",
- hwnd, nBar, fShowH, fShowV );
+ TRACE("hwnd=%04x nBar=%d fShow=%d\n", hwnd, nBar, fShow);
- switch(nBar)
+ /* change the show state as requested */
+ switch (nBar)
{
case SB_CTL:
- ShowWindow( hwnd, fShowH ? SW_SHOW : SW_HIDE );
+ ShowWindow(hwnd, fShow ? SW_SHOW : SW_HIDE);
return TRUE;
case SB_BOTH:
case SB_HORZ:
- if (fShowH)
- {
- fShowH = !(style & WS_HSCROLL);
+ if (fShow)
style |= WS_HSCROLL;
- }
else /* hide it */
- {
- fShowH = (style & WS_HSCROLL);
style &= ~WS_HSCROLL;
- }
- if( nBar == SB_HORZ ) {
- fShowV = FALSE;
- break;
- }
- /* fall through */
-
+ if (nBar == SB_HORZ) break;
+ /* fall through */
case SB_VERT:
- if (fShowV)
- {
- fShowV = !(style & WS_VSCROLL);
+ if (fShow)
style |= WS_VSCROLL;
- }
- else /* hide it */
- {
- fShowV = (style & WS_VSCROLL);
+ else /* hide it */
style &= ~WS_VSCROLL;
- }
- if ( nBar == SB_VERT )
- fShowH = FALSE;
- break;
-
default:
- return FALSE; /* Nothing to do! */
+ break;
}
- if( fShowH || fShowV ) /* frame has been changed, let the window redraw
itself */
+ /* update the window if frame has changed */
+ if (style != oldStyle)
{
- WIN_SetStyle( hwnd, style );
- SetWindowPos( hwnd, 0, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE
- | SWP_NOACTIVATE | SWP_NOZORDER | SWP_FRAMECHANGED );
- return TRUE;
+ WIN_SetStyle(hwnd, style);
+ SetWindowPos(hwnd, 0, 0, 0, 0, 0, SWP_NOSIZE | SWP_NOMOVE |
+ SWP_NOACTIVATE | SWP_NOZORDER | SWP_FRAMECHANGED);
}
- return FALSE; /* no frame changes */
-}
-
-
-/*************************************************************************
- * ShowScrollBar (USER32.@)
- *
- * RETURNS STD
- */
-BOOL WINAPI ShowScrollBar(
-HWND hwnd, /* [in] Handle of window whose scrollbar(s) will be affected */
-INT nBar, /* [in] One of SB_HORZ, SB_VERT, SB_BOTH or SB_CTL */
-BOOL fShow /* [in] TRUE = show, FALSE = hide */)
-{
- SCROLL_ShowScrollBar( hwnd, nBar, (nBar == SB_VERT) ? 0 : fShow,
- (nBar == SB_HORZ) ? 0 : fShow );
return TRUE;
}
/*************************************************************************
* EnableScrollBar (USER32.@)
+ *
+ * RETURNS STD
*/
-BOOL WINAPI EnableScrollBar( HWND hwnd, INT nBar, UINT flags )
+BOOL WINAPI EnableScrollBar(
+HWND hwnd /* [in] Handle of window with scrollbar(s) */,
+INT nBar /* [in] One of SB_HORZ, SB_VERT, SB_BOTH or SB_CTL */,
+UINT flags /* [in] Flags indicating which scroll bars to enable */)
{
- BOOL bFineWithMe;
- SCROLLBAR_INFO *infoPtr;
-
- TRACE("%04x %d %d\n", hwnd, nBar, flags );
+ BOOL ret = TRUE;
+ LPSCROLLBAR_INFO info;
- flags &= ESB_DISABLE_BOTH;
+ TRACE("hwnd=%04x nBar=%d flags=%04x\n", hwnd, nBar, flags);
+ /* use recursion to handle the case of two scroll bars */
if (nBar == SB_BOTH)
{
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, SB_VERT ))) return FALSE;
- if (!(bFineWithMe = (infoPtr->flags == flags)) )
- {
- infoPtr->flags = flags;
- SCROLL_RefreshScrollBar( hwnd, SB_VERT, TRUE, TRUE );
- }
- nBar = SB_HORZ;
+ ret = EnableScrollBar(hwnd, SB_VERT, flags);
+ nBar = SB_HORZ;
}
- else
- bFineWithMe = TRUE;
- if (!(infoPtr = SCROLL_GetScrollInfo( hwnd, nBar ))) return FALSE;
- if (bFineWithMe && infoPtr->flags == flags) return FALSE;
- infoPtr->flags = flags;
+ /* change the enable flags of the bar and redraw if necessary */
+ flags &= ~ESB_DISABLE_BOTH;
+ info = SCROLL_GetScrollInfo(hwnd, nBar);
+ ret = ret && info && (info->flags != flags);
+ if (ret)
+ {
+ info->flags = flags;
+ if (WIN_IsWindowDrawable(hwnd, FALSE))
+ SCROLL_RefreshScrollBar(hwnd, nBar, TRUE, TRUE);
+ }
- SCROLL_RefreshScrollBar( hwnd, nBar, TRUE, TRUE );
- return TRUE;
+ return ret;
}
