XProfan

Except for trackbars, which use the WM_HSCROLL and WM_VSCROLL messages to notify its parent of changes, common controls send notification messages as WM_NOTIFY messages. The lParam parameter of WM_NOTIFY is either the address of an NMHDR structure or the address of a larger structure that includes NMHDR as its first member. The structure contains the notification code and identifies the common control that sent the notification message. The meaning of the remaining structure members, if any, varies depending on the notification code.

Flat Scroll Bars
Microsoft® Internet Explorer Version 4.0 introduces a new visual technology called flat scroll bars. Functionally, flat scroll bars behave just like normal scroll bars. The only difference is they are not displayed three-dimensionally.

Using Flat Scroll Bars
This section describes how to implement flat scroll bars in your application.
Before You Begin
To use the flat scroll bar APIs, you must include Commctrl.h in your source files and link with Comctl32.lib.
Adding Flat Scroll Bars to a Window
To add flat scroll bars to a window, call InitializeFlatSB, passing the handle to the window. Instead of using the standard scroll bar APIs to manipulate your scroll bars, you must use the FlatSB_xxxx versions. There are flat scroll bar APIs for setting and retrieving the scroll information, range, and position. If flat scroll bars havent been initialized for your window, the flat scroll bar APIs will defer to the corresponding standard APIs, if any exist. This allows you to turn flat scroll bars on and off without having to write conditional code.
Because an application may have set custom metrics for its flat scroll bars, they are not automatically updated when system metrics change. When the system scroll bar metrics change, a WM_SETTINGCHANGE message is broadcast, with its wParam set to SPI_SETNONCLIENTMETRICS. To update flat scroll bars to the new system metrics, applications must handle this message, and change the flat scroll bars metric-dependent properties explicitly.
To update your scroll bar properties, use FlatSB_SetScrollProp. The following code fragment changes a flat scroll bars metric dependent properties to the current system values.
void FlatSB_UpdateMetrics(HWND hWnd)
{
FlatSB_SetScrollProp(hWnd, WSB_PROP_CXVSCROLL, GetSystemMetrics(SM_CXVSCROLL), FALSE);
FlatSB_SetScrollProp(hWnd, WSB_PROP_CXHSCROLL, GetSystemMetrics(SM_CXHSCROLL), FALSE);
FlatSB_SetScrollProp(hWnd, WSB_PROP_CYVSCROLL, GetSystemMetrics(SM_CYVSCROLL), FALSE);
FlatSB_SetScrollProp(hWnd, WSB_PROP_CYHSCROLL, GetSystemMetrics(SM_CYHSCROLL), FALSE);
FlatSB_SetScrollProp(hWnd, WSB_PROP_CXHTHUMB, GetSystemMetrics(SM_CXHTHUMB), FALSE);
FlatSB_SetScrollProp(hWnd, WSB_PROP_CYVTHUMB, GetSystemMetrics(SM_CYVTHUMB), TRUE);
}
Enhancing Flat Scroll Bars
FlatSB_SetScrollProp allows you to modify the flat scroll bars to customize the look of your window. You can set the width of a vertical scroll bar and the height of a horizontal scroll bar. You can also set the width (horizontal scroll bar) and the height (vertical scroll bar) of the scroll bars direction arrows.
FlatSB_SetScrollProp also allows you to customize how the flat scroll bars are displayed. By changing the WSB_PROP_VSTYLE and WSB_PROP_HSTYLE properties, you can set the type of scroll bar that you wish to use. Three styles are available:
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects will be applied.
Removing Flat Scroll Bars
If you wish to remove flat scroll bars from your window, call the UninitializeFlatSB API, passing the handle to the window. This API only removes flat scroll bars from your window at run time. You do not need to call this API when your window is destroyed.

Flat Scroll Bar Functions
InitializeFlatSB
Initializes flat scroll bars for a particular window.
BOOL InitializeFlatSB(
HWND hwnd
);
Parameters
hwnd
Handle to the window that will receive flat scroll bars.
Return Values
Returns nonzero if successful, or zero otherwise.
Remarks
This API must be called before any other flat scroll bar APIs are called. The window will receive flat scroll bars by default. The scroll bar style can be changed with the FlatSB_SetScrollProp API.
FlatSB_EnableScrollBar
Enables or disables one or both flat scroll bar direction buttons. If flat scroll bars are not initialized for the window, this function calls the standard EnableScrollBar API.
BOOL FlatSB_EnableScrollBar(
HWND hwnd,
int wSBflags,
UINT wArrows
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
wSBflags
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_BOTH
Enables or disables the direction buttons on the horizontal and vertical scroll bars.
SB_HORZ
Enables or disables the direction buttons on the horizontal scroll bar.
SB_VERT
Enables or disables the direction buttons on the vertical scroll bar.
wArrows
Parameter that specifies whether the scroll bar arrows are enabled or disabled and indicates which arrows are enabled or disabled. It can be one of the following values:
ESB_DISABLE_BOTH
Disables both direction buttons on the specified scroll bar.
ESB_DISABLE_DOWN
Disables the down direction button on the vertical scroll bar.
ESB_DISABLE_LEFT
Disables the left direction button on the horizontal scroll bar.
ESB_DISABLE_LTUP
Disables the left direction button on the horizontal scroll bar or the up direction button on the vertical scroll bar.
ESB_DISABLE_RIGHT
Disables the right direction button on the horizontal scroll bar.
ESB_DISABLE_RTDN
Disables the right direction button on the horizontal scroll bar or the down direction button on the vertical scroll bar.
ESB_DISABLE_UP
Disables the up direction button on the vertical scroll bar.
ESB_ENABLE_BOTH
Enables both direction buttons on the specified scroll bar.
Return Values
Returns nonzero if the scroll bar changes, or zero otherwise.
FlatSB_GetScrollInfo
Retrieves the information for a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard GetScrollInfo API.
BOOL FlatSB_GetScrollInfo(
HWND hwnd,
int fnBar,
LPSCROLLINFO lpsi
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
fnBar
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Retrieves the information for the horizontal scroll bar.
SB_VERT
Retrieves the information for the vertical scroll bar.
lpsi
Address of a SCROLLINFO structure that will receive the information for the specified scroll bar. The cbSize and fMask members of the structure must be filled out prior to calling FlatSB_GetScrollInfo. The fMask member specifies which properties should be retrieved and can be any combination of the following values:
SIF_PAGE
Retrieves the page information for the flat scroll bar. This will be placed in the nPage member of the SCROLLINFO structure.
SIF_POS
Retrieves the position information for the flat scroll bar. This will be placed in the nPos member of the SCROLLINFO structure.
SIF_RANGE
Retrieves the range information for the flat scroll bar. This will be placed in the nMin and nMax members of the SCROLLINFO structure.
SIF_ALL
A combination of SIF_PAGE, SIF_POS, and SIF_RANGE.
Return Values
Returns nonzero if successful, or zero otherwise.
FlatSB_GetScrollPos
Retrieves the thumb position in a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard GetScrollPos API.
int FlatSB_GetScrollPos(
HWND hwnd,
int code
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
code
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Retrieves the thumb position of the horizontal scroll bar.
SB_VERT
Retrieves the thumb position of the vertical scroll bar.
Return Values
Returns the current thumb position of the specified flat scroll bar.
FlatSB_GetScrollProp
Retrieves the properties for a flat scroll bar. This function can also be used to determine if InitializeFlatSB has been called for this window.
BOOL FlatSB_GetScrollProp(
HWND hwnd,
UINT index,
LPINT pValue
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
index
Parameter that determines what pValue represents and which property is being retrieved. It can be one of the following values:
WSB_PROP_CXHSCROLL
pValue is an address of an INT value that receives the width, in pixels, of the direction buttons in a horizontal scroll bar.
WSB_PROP_CXHTHUMB
pValue is an address of an INT value that receives the width, in pixels, of the thumb in a horizontal scroll bar.
WSB_PROP_CXVSCROLL
pValue is an address of an INT value that receives the width, in pixels, of a vertical scroll bar.
WSB_PROP_CYHSCROLL
pValue is an address of an INT value that receives the height, in pixels, of a horizontal scroll bar.
WSB_PROP_CYVSCROLL
pValue is an address of an INT value that receives the height, in pixels, of the direction buttons in a vertical scroll bar.
WSB_PROP_CYVTHUMB
pValue is an address of an INT value that receives the height, in pixels, of the thumb in a vertical scroll bar.
WSB_PROP_HBKGCOLOR
pValue is an address of a COLORREF value that receives the background color in a horizontal scroll bar.
WSB_PROP_HSTYLE
pValue is an address of an INT value that receives one of the following visual effects for the horizontal scroll bar.
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar is displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar is displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects are applied.
WSB_PROP_PALETTE
pValue is an address of an HPALETTE value that receives the palette that a scroll bar uses when drawing.
WSB_PROP_VBKGCOLOR
pValue is an address of a COLORREF value that receives the background color in a vertical scroll bar.
WSB_PROP_VSTYLE
pValue is an address of an INT value that receives one of the following visual effects for the vertical scroll bar.
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar is displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar is displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects are applied.
WSB_PROP_WINSTYLE
pValue is an address of an INT value that receives the WS_HSCROLL and WS_VSCROLL style bits contained by the current window.
pValue
Address that receives the requested data. This parameter depends on the flag passed in index.
Return Values
Returns nonzero if successful, or zero otherwise. If index is WSB_PROP_HSTYLE, the return is nonzero if InitializeFlatSB has been called for this window, or zero otherwise.
FlatSB_GetScrollRange
Retrieves the scroll range for a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard GetScrollRange API.
BOOL FlatSB_GetScrollRange(
HWND hwnd,
int code,
LPINT lpMinPos,
LPINT lpMaxPos
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
code
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Retrieves the scroll range of the horizontal scroll bar.
SB_VERT
Retrieves the scroll range of the vertical scroll bar.
lpMinPos
Address of an INT value that receives the minimum scroll range value.
lpMaxPos
Address of an INT value that receives the maximum scroll range value.
Return Values
Returns nonzero if successful, or zero otherwise.
FlatSB_SetScrollInfo
Sets the information for a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard SetScrollInfo API.
int FlatSB_SetScrollInfo(
HWND hwnd,
int fnBar,
LPSCROLLINFO lpsi,
BOOL fRedraw
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
fnBar
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Sets the information for the horizontal scroll bar.
SB_VERT
Sets the information for the vertical scroll bar.
lpsi
Address of a SCROLLINFO structure that contains the new information for the specified scroll bar. The cbSize and fMask members of the structure must be filled in prior to calling FlatSB_SetScrollInfo. The fMask member specifies which members of the structure contain valid information and can be any combination of the following values:
SIF_DISABLENOSCROLL
Disables the scroll bar if the new information would cause the scroll bar to be removed.
SIF_PAGE
Sets the page information for the flat scroll bar. The nPage member of the SCROLLINFO structure must contain the new page value.
SIF_POS
Sets the position information for the flat scroll bar. The nPos member of the SCROLLINFO structure must contain the new position value.
SIF_RANGE
Sets the range information for the flat scroll bar. The nMin and nMax members of the SCROLLINFO structure must contain the new range values.
SIF_ALL
A combination of SIF_PAGE, SIF_POS, and SIF_RANGE.
fRedraw
Parameter that specifies whether the scroll bar should be redrawn immediately to reflect the change. If this parameter is TRUE, the scroll bar is redrawn; if it is FALSE, the scroll bar is not redrawn.
Return Values
Returns the current scroll position. If the call to FlatSB_SetScrollInfo changes the scroll position, then the previous position is returned.
FlatSB_SetScrollPos
Sets the current position of the thumb in a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard SetScrollPos API.
int FlatSB_SetScrollPos(
HWND hwnd,
int code,
int nPos,
BOOL fRedraw
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
code
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Sets the thumb position of the horizontal scroll bar.
SB_VERT
Sets the thumb position of the vertical scroll bar.
nPos
Parameter that specifies the new thumb position.
fRedraw
Parameter that specifies whether the scroll bar should be redrawn immediately to reflect the change. If this parameter is TRUE, the scroll bar is redrawn; if it is FALSE, the scroll bar is not redrawn.
Return Values
Returns the previous position of the thumb in the specified flat scroll bar.
FlatSB_SetScrollProp
Sets the properties for a flat scroll bar.
BOOL FlatSB_SetScrollProp(
HWND hwnd,
UINT index,
int newValue,
BOOL fRedraw
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
index
Parameter that determines what newValue represents and which property is being set. This parameter can be one of the following values:

WSB_PROP_CXHSCROLL
newValue is an INT value that represents the width, in pixels, of the direction buttons in a horizontal scroll bar.
WSB_PROP_CXHTHUMB
newValue is an INT value that represents the width, in pixels, of the thumb in a horizontal scroll bar.
WSB_PROP_CXVSCROLL
newValue is an INT value that represents the width, in pixels, of the vertical scroll bar.
WSB_PROP_CYHSCROLL
newValue is an INT value that represents the height, in pixels, of the horizontal scroll bar.
WSB_PROP_CYVSCROLL
newValue is an INT value that represents the height, in pixels, of the direction buttons in a vertical scroll bar.
WSB_PROP_CYVTHUMB
newValue is an INT value that represents the height, in pixels, of the thumb in a vertical scroll bar.
WSB_PROP_HBKGCOLOR
newValue is a COLORREF value that represents the background color in a horizontal scroll bar.
WSB_PROP_HSTYLE
newValue is one of the following values that changes the visual effects for the horizontal scroll bar.
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects will be applied.
WSB_PROP_PALETTE
newValue is an HPALETTE value that represents the new palette that the scroll bar should use when drawing.
WSB_PROP_VBKGCOLOR
newValue is a COLORREF value that represents the background color in a vertical scroll bar.
WSB_PROP_VSTYLE
newValue is one of the following values that changes the visual effects for the vertical scroll bar:
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects will be applied.
newValue
New value to set. This parameter depends on the flag passed in index.
fRedraw
Parameter that specifies whether the scroll bar should be redrawn immediately to reflect the change. If this parameter is TRUE, the scroll bar is redrawn; if it is FALSE, the scroll bar is not redrawn.
Return Values
Returns nonzero if successful, or zero otherwise.
FlatSB_SetScrollRange
Sets the scroll range of a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard SetScrollRange API.
int FlatSB_SetScrollRange(
HWND hwnd,
int code,
int nMinPos,
int nMaxPos,
BOOL fRedraw
);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
code
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_HORZ
Sets the scroll range of the horizontal scroll bar.
SB_VERT
Sets the scroll range of the vertical scroll bar.
nMinPos
Parameter that specifies the new minimum scroll range value.
nMaxPos
Parameter that specifies the new maximum scroll range value.
fRedraw
Parameter that specifies whether the scroll bar should be redrawn immediately to reflect the change. If this parameter is TRUE, the scroll bar is redrawn; if it is FALSE, the scroll bar is not redrawn.
Return Values
Returns nonzero if successful, or zero otherwise.
FlatSB_ShowScrollBar
Shows or hides a flat scroll bar. If flat scroll bars are not initialized for the window, this function calls the standard ShowScrollBar API.

BOOL FlatSB_ShowScrollBar(HWND hwnd, int code, BOOL fShow);
Parameters
hwnd
Handle to the window that contains the flat scroll bar. This window handle must have been passed previously in a call to InitializeFlatSB.
code
Parameter that specifies the scroll bar type. It can be one of the following values:
SB_BOTH
Shows or hides the horizontal and vertical scroll bars.
SB_HORZ
Shows or hides the horizontal scroll bar.
SB_VERT
Shows or hides the vertical scroll bar.
fShow
Parameter that specifies whether the scroll bar should be shown or hidden. If this parameter is nonzero, the scroll bar will be shown; if it is zero, the scroll bar will be hidden.
Return Values
Returns nonzero if successful, or zero otherwise.
UninitializeFlatSB
Uninitializes flat scroll bars for a particular window. The specified window will revert to having standard scroll bars.
HRESULT UninitializeFlatSB(
HWND hwnd
);
Parameters
hwnd
Handle to the window with the flat scroll bars that will be uninitialized.
Return Values
Returns one of the following values:

E_FAIL
One of the windows scroll bars is currently in use. The operation cannot be completed at this time.
S_FALSE
The window doesnt have flat scroll bars initialized.
S_OK
The operation was successful.

WSB_PROP_CXHSCROLL
newValue is an INT_PTR value that represents the width, in pixels, of the direction buttons in a horizontal scroll bar.
WSB_PROP_CXHTHUMB
newValue is an INT_PTR value that represents the width, in pixels, of the thumb in a horizontal scroll bar.
WSB_PROP_CXVSCROLL
newValue is an INT_PTR value that represents the width, in pixels, of the vertical scroll bar.
WSB_PROP_CYHSCROLL
newValue is an INT_PTR value that represents the height, in pixels, of the horizontal scroll bar.
WSB_PROP_CYVSCROLL
newValue is an INT_PTR value that represents the height, in pixels, of the direction buttons in a vertical scroll bar.
WSB_PROP_CYVTHUMB
newValue is an INT_PTR value that represents the height, in pixels, of the thumb in a vertical scroll bar.
WSB_PROP_HBKGCOLOR
newValue is a COLORREF value that represents the background color in a horizontal scroll bar.
WSB_PROP_HSTYLE
newValue is one of the following values that changes the visual effects for the horizontal scroll bar.
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects will be applied.
WSB_PROP_PALETTE
newValue is an HPALETTE value that represents the new palette that the scroll bar should use when drawing.
WSB_PROP_VBKGCOLOR
newValue is a COLORREF value that represents the background color in a vertical scroll bar.
WSB_PROP_VSTYLE
newValue is one of the following values that changes the visual effects for the vertical scroll bar:
FSB_ENCARTA_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in 3-D.
FSB_FLAT_MODE
A standard flat scroll bar is displayed. When the mouse moves over a direction button or the thumb, that portion of the scroll bar will be displayed in inverted colors.
FSB_REGULAR_MODE
A normal, nonflat scroll bar is displayed. No special visual effects will be applied.