DROPDOWN

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DROPDOWN widgets are used to select one element of a list with several columns. It shows the currently selected item in non open state. If the user opens a DROPDOWN widget a LISTBOX appears to select a new item.

DROPDOWN
Opened DROPDOWN with new skin.
Receives focus Yes
Skinnable Yes
OwnerDraw No
Uses Memory Devices No
Attached widgets

Notification codes

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

Message Description
WM_NOTIFICATION_CLICKED DROPDOWN has been clicked.
WM_NOTIFICATION_RELEASED DROPDOWN has been released.
WM_NOTIFICATION_MOVED_OUT DROPDOWN has been clicked and pointer has been moved out of the DROPDOWN widget without releasing.
WM_NOTIFICATION_SCROLL_CHANGED The scroll position of the optional scroll bar of the opened DROPDOWN widget has been changed.
WM_NOTIFICATION_SEL_CHANGED The selection of the DROPDOWN list has been changed.

Keyboard reaction

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

Message Description
GUI_KEY_ENTER Selects an item from the open DROPDOWN list and closes the list.
GUI_KEY_SPACE Opens the DROPDOWN list.

Samples

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