Edit

BCN_DROPDOWN notification code

  • Article

Sent when the user clicks a drop down arrow on a button. The parent window of the control receives this notification code in the form of a WM_NOTIFY message.

BCN_DROPDOWN
        
    pnmdropdown = (NMBCDROPDOWN*) lParam;

Parameters

lParam

A pointer to a NMBCDROPDOWN structure. The rcButton member is set to describe the drop-down area.

Return value

No return value.

Remarks

The notification receiver casts LPARAM to retrieve the NMBCDROPDOWN structure. WPARAM contains the ID of the control that sends this message. The button control must have a drop-down button style.

Requirements

Requirement Value
Minimum supported client
 Windows Vista [desktop apps only]
Minimum supported server
 Windows Server 2008 [desktop apps only]
Header
Winuser.h (include Windows.h)