You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: combobox.go
    path of file: ./repos/wails/v2/internal/frontend/desktop/windows/winc
    
    the code of the file until where you have to start completion: //go:build windows

/*
 * Copyright (C) 2019 The Winc Authors. All Rights Reserved.
 */

package winc

import 
    
func (cb *ComboBox) WndProc(msg uint32, wparam, lparam uintptr) uintptr {
	switch msg {
	case w32.WM_COMMAND:
		code := w32.HIWORD(uint32(wparam))

		switch code {
		case w32.CBN_SELCHANGE:
			cb.onSelectedChange.Fire(NewEvent(cb, nil))
		}
	}
	return w32.DefWindowProc(cb.hwnd, msg, wparam, lparam)
	//return cb.W32Control.WndProc(msg, wparam, lparam)
}