|
Overview |
|
|
|
Group |
|
|
|
Quick Info
Windows NT
| Yes
| Win95
| Yes
| Win32s
| Yes
| Import Library
| user32.lib
| Header File
| winuser.h
| Unicode
| No
| Platform Notes
| None
|
|
|
GetScrollPos
The GetScrollPos function retrieves the current position of the scroll box (thumb) in the
specified scroll bar. The current position is a relative value that depends on the
current scrolling range. For example, if the scrolling range is 0 through 100
and the scroll box is in the middle of the bar, the current position is 50.
int GetScrollPos(
HWND hWnd,
| // handle of window with scroll bar
| int nBar
| // scroll bar flags
| );
|
|
Parameters
hWnd
Identifies a scroll bar control or a window with a standard scroll bar,
depending on the value of the nBar parameter.
nBar
Specifies the scroll bar to be examined. This parameter can be one of the
following values:
Value
| Meaning
| SB_CTL
| Retrieves the position of the scroll box in a scroll bar control. The hWnd parameter must be the handle of the scroll bar control.
| SB_HORZ
| Retrieves the position of the scroll box in a window's standard horizontal
scroll bar.
| SB_VERT
| Retrieves the position of the scroll box in a window's standard vertical
scroll bar.
|
Return Values
If the function succeeds, the return value is the current position of the
scroll box/
If the function fails, the return value is zero. To get extended error
information, call GetLastError.
Remarks
The GetScrollPos function enables applications to use 32-bit scroll positions. Although the
messages that indicate scroll bar position, WM_HSCROLL and WM_VSCROLL, are
limited to 16 bits of position data, the functions SetScrollPos, SetScrollRange, GetScrollPos, and GetScrollRange support 32-bit scroll bar position data. Thus, an application can call GetScrollPos while processing either the WM_HSCROLL or WM_VSCROLL messages to obtain 32-bit scroll bar position data.
The limitation on this technique applies to real-time scrolling of a window's
content. An application implements such scrolling by processing the WM_HSCROLL
or WM_VSCROLL messages that carry the SB_THUMBTRACK notification message,
thereby tracking the position of the scroll box, also known as the thumb, while the
user moves it. Unfortunately, there is no function to retrieve the thumb's
32-bit position while the user moves it. GetScrollPos provides static position data only; an application can therefore only obtain
32-bit position data before or after a scroll has taken place.
See Also
GetScrollRange, ScrollDC, ScrollWindow, SetScrollPos, SetScrollRange, WM_HSCROLL, WM_VSCROLL
Related Links
Software for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
More Online Helps
Win32 Programmer's Reference (win32.hlp)
Win32 Multimedia Programmer's Reference (mmedia.hlp)
OLE Programmer's Reference (ole.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (tapi.hlp)
Unix Manual Pages
|
