// MustRegisterWindowClass registers the specified window class.
//
// MustRegisterWindowClass must be called once for every window type that is not
// based on any system provided control, before calling InitChildWidget or
// InitWidget. Calling MustRegisterWindowClass twice with the same className
// results in a panic.
func MustRegisterWindowClass(className string) {
if registeredWindowClasses[className] {
panic("window class already registered")
}
hInst := win.GetModuleHandle(nil)
if hInst == 0 {
panic("GetModuleHandle")
}
hIcon := win.LoadIcon(0, (*uint16)(unsafe.Pointer(uintptr(win.IDI_APPLICATION))))
if hIcon == 0 {
panic("LoadIcon")
}
hCursor := win.LoadCursor(0, (*uint16)(unsafe.Pointer(uintptr(win.IDC_ARROW))))
if hCursor == 0 {
panic("LoadCursor")
}
var wc win.WNDCLASSEX
wc.CbSize = uint32(unsafe.Sizeof(wc))
wc.LpfnWndProc = defaultWndProcPtr
wc.HInstance = hInst
wc.HIcon = hIcon
wc.HCursor = hCursor
wc.HbrBackground = win.COLOR_BTNFACE + 1
wc.LpszClassName = syscall.StringToUTF16Ptr(className)
if atom := win.RegisterClassEx(&wc); atom == 0 {
panic("RegisterClassEx")
}
registeredWindowClasses[className] = true
}
// NewIconFromResource returns a new Icon, using the specified icon resource.
func NewIconFromResource(resName string) (ic *Icon, err error) {
var lpIconName *uint16
hInst := win.GetModuleHandle(nil)
if hInst == 0 {
err = lastError("GetModuleHandle")
return
}
if id, atoierr := strconv.Atoi(resName); atoierr == nil {
lpIconName = (*uint16)(unsafe.Pointer(uintptr(id)))
} else {
lpIconName = syscall.StringToUTF16Ptr(resName)
}
if hIcon := win.LoadIcon(hInst, lpIconName); hIcon == 0 {
err = lastError("LoadIcon")
} else {
ic = &Icon{hIcon: hIcon}
}
return
}
func NewBitmapFromResource(resName string) (b *Bitmap, err error) {
var lpBitMapName *uint16
hInst := win.GetModuleHandle(nil)
if hInst == 0 {
err = lastError("GetModuleHandle")
return
}
if id, atoierr := strconv.Atoi(resName); atoierr == nil {
lpBitMapName = (*uint16)(unsafe.Pointer(uintptr(id)))
} else {
lpBitMapName = syscall.StringToUTF16Ptr(resName)
}
if hBitMap := win.LoadBitmap(hInst, lpBitMapName); hBitMap == 0 {
err = lastError("LoadBitmap")
} else {
b = &Bitmap{hBmp: hBitMap}
}
return
}