func (w *WindowBase) Handle() win.HWND {
	return w.hwnd
}
Handle get hwnd.
package wingui
import (
	"syscall"
	"unsafe"
	"github.com/lxn/win"
)
type WindowBase struct {
	hwnd win.HWND
	idd uintptr
	lpPrevWndFunc uintptr
	Subclassing bool
}
func (w *WindowBase) AsWindowBase() *WindowBase {
	return w
}
func (w *WindowBase) Init(hwnd win.HWND, idd uintptr) {
	w.hwnd = hwnd
	w.idd = idd
}