SCROLLBAR

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SCROLLBAR widgets are used for scrolling through list boxes or any other type of window. They may be created horizontally or vertically. A scroll bar is typically attached to an existing window.

SCROLLBAR
SCROLLBAR with new skin.
Receives focus Yes
Skinnable Yes
OwnerDraw No
Uses Memory Devices No
Attached widgets None

Notification codes

The following events are sent from a SCROLLBAR widget to its parent window as part of a WM_NOTIFY_PARENT message:

Message Description
WM_NOTIFICATION_CLICKED SCROLLBAR has been clicked.
WM_NOTIFICATION_RELEASED SCROLLBAR has been released.
WM_NOTIFICATION_SCROLLBAR_ADDED SCROLLBAR has just been added (attached) to an existing window. The window needs to be informed so that it can initialize the scroll bar.
WM_NOTIFICATION_VALUE_CHANGED Value of SCROLLBAR has changed, either by moving the thumb or by pressing the arrow buttons.

Keyboard reaction

The SCROLLBAR widget reacts to the following keys if it has the input focus:

Message Description
GUI_KEY_RIGHT Increments the current value of the SCROLLBAR widget by 1.
GUI_KEY_DOWN Increments the current value of the SCROLLBAR widget by 1.
GUI_KEY_PGDOWN Increments the current value of the SCROLLBAR widget by a value which represents 1 page.
GUI_KEY_LEFT Decrements the current value of the SCROLLBAR widget by 1.
GUI_KEY_UP Decrements the current value of the SCROLLBAR widget by 1.
GUI_KEY_PGUP Decrements the current value of the SCROLLBAR widget by a value which represents 1 page.

Samples

Below are links to samples that demonstrate how to use SCROLLBAR widgets in emWin.