BCGControlBar Pro for MFC
void CBCGPColorProp::EnableOtherButton ( LPCTSTR  lpszLabel,
BOOL  bAltColorDlg = TRUE,
BOOL  bEnable = TRUE 
)

Enables the ability to invoke an additional color selection dialog.

Use this method to allow the user to select a custom color from the color dialog. When "Other" button is enabled, it appears on the popup color bar.

Parameters
lpszLabelThe button's text.
bAltColorDlgSpecifies whether the standard or BCGControlBar Library-provided color selection dialog should be invoked.
bEnableSpecifies whether the "Other" button should appear or not