func DetachWindowEventHandler(hwnd uint32) {
key := uintptr(hwnd)
if handler, exists := windowEventHandlers[hwnd]; exists {
tag := uintptr(unsafe.Pointer(handler))
if ret := C.HTMLayoutWindowDetachEventHandler(C.HWND(C.HANDLE(key)), (*[0]byte)(unsafe.Pointer(goElementProc)), C.LPVOID(tag)); ret != HLDOM_OK {
domPanic(ret, "Failed to detach event handler from window")
}
delete(windowEventHandlers, hwnd)
}
}
func AttachWindowEventHandler(hwnd uint32, handler *EventHandler) {
key := uintptr(hwnd)
tag := uintptr(unsafe.Pointer(handler))
if _, exists := windowEventHandlers[hwnd]; exists {
if ret := C.HTMLayoutWindowDetachEventHandler(C.HWND(C.HANDLE(key)), (*[0]byte)(unsafe.Pointer(goElementProc)), C.LPVOID(tag)); ret != HLDOM_OK {
domPanic(ret, "Failed to detach event handler from window before adding the new one")
}
}
// Overwrite if it exists
windowEventHandlers[hwnd] = handler
// Don't let the caller disable ATTACH/DETACH events, otherwise we
// won't know when to throw out our event handler object
subscription := handler.Subscription()
subscription &= ^uint32(DISABLE_INITIALIZATION & 0xffffffff)
if ret := C.HTMLayoutWindowAttachEventHandler(C.HWND(C.HANDLE(key)), (*[0]byte)(unsafe.Pointer(goElementProc)), C.LPVOID(tag), C.UINT(subscription)); ret != HLDOM_OK {
domPanic(ret, "Failed to attach event handler to window")
}
}