WM VSCROLL

This message occurs when a vertical scroll-bar control has a significant event to notify to its owner.

Syntax

param1
    USHORT  usidentifier;  /* Scroll bar-control window identifier. */

param2
    SHORT   sslider;       /* Slider position. */
    USHORT  uscmd;         /* Command. */

Parameters

usidentifier (USHORT) - input

Scroll bar-control window identifier.

sslider (SHORT) - input

Slider position.

0: Either the operator is not moving the slider with the pointer device, or for the instance when uscmd is SB_SLIDERPOSITION the pointer is outside the tracking rectangle when the button is released.

Other: Slider position.

uscmd (USHORT) - input

Command.

SB_LINEUP: Sent if the operator clicks on the up arrow of the scroll bar, or presses the VK_UP key.

SB_LINEDOWN: Sent if the operator clicks on the down arrow of the scroll bar, or presses the VK_DOWN key.

SB_PAGEUP: Sent if the operator clicks on the area above the slider, or presses the VK_PAGEUP key.

SB_PAGEDOWN: Sent if the operator clicks on the area below the slider, or presses the VK_PAGEDOWN key.

SB_SLIDERPOSITION: Sent to indicate the final position of the slider.

SB_SLIDERTRACK: If the operator moves the scroll bar slider with the pointer device, this is sent every time the slider position changes.

SB_ENDSCROLL: Sent when the operator has finished scrolling, but only if the operator has not been doing any absolute slider positioning.

Returns

ulReserved (ULONG) - returns

Reserved value, should be 0.

Remarks

in Vertical Scroll Bars

The scroll bar control window procedure generates this message and posts the message to the owner of the procedure, informing the owner of the event.

Default Processing

The default window procedure takes no action on this message, other than to set ulReserved to 0.

in Vertical Scroll Bars

The default window procedure takes no action on this message, other than to set ulReserved to 0.

Related Messages

• WM_VSCROLL (in Vertical Scroll Bars)