DialogProc is registered with the dialog window when the Styler page is inserted into the Settings notebook. The dialog procedure gets control when the Styler page is given focus.
The dialog procedure catches all WM_FOCUSCHANGE messages to provide an information message for each control on the Styler settings page. As the user tabs between each control on the Styler page, an information message describing the control is displayed just above the push buttons.
An Apply push button is provided so that a user can apply the changes instantly without closing the Styler page.