void FWindowsTextInputMethodSystem::ApplyDefaults(const TSharedRef<FGenericWindow>& InWindow)
{
ClearStaleWindowHandles();
KnownWindows.Add(InWindow);
const HWND Hwnd = reinterpret_cast<HWND>(InWindow->GetOSWindowHandle());
// Typically we disable the IME when a new window is created, however, we don't want to do that if we have an active context,
// as it will immediately disable the IME (which may be undesirable for things like a search suggestions window appearing)
// In that case, we set the window to use the same IME context as is currently active. If the window actually takes focus
// away from the currently active IME context, then that will be taken care of in DeactivateContext, and all windows using the
// IME context will be disabled
ITfDocumentMgr* TSFDocumentManagerToSet = nullptr;
HIMC IMMContextToSet = nullptr;
if(ActiveContext.IsValid())
{
TSFThreadManager->GetFocus(&TSFDocumentManagerToSet);
IMMContextToSet = IMMContextId;
}
// TSF Implementation
if(TSFDocumentManagerToSet)
{
TSFThreadManager->SetFocus(TSFDocumentManagerToSet);
}
else
{
ITfDocumentMgr* Unused;
TSFThreadManager->AssociateFocus(Hwnd, TSFDisabledDocumentManager, &Unused);
}
// IMM Implementation
::ImmAssociateContext(Hwnd, IMMContextToSet);
}
void FWindowsTextInputMethodSystem::DeactivateContext(const TSharedRef<ITextInputMethodContext>& Context)
{
UE_LOG(LogWindowsTextInputMethodSystem, Verbose, TEXT("Deactivating context %p..."), &(Context.Get()));
FInternalContext& InternalContext = ContextToInternalContextMap[Context];
// IMM Implementation
HIMC IMMContext = ::ImmGetContext(InternalContext.WindowHandle);
InternalContext.IMMContext.IsDeactivating = true;
// Request the composition is completed to ensure that the composition input UI is closed, and that a WM_IME_ENDCOMPOSITION message is sent
::ImmNotifyIME(IMMContext, NI_COMPOSITIONSTR, CPS_COMPLETE, 0);
::ImmReleaseContext(InternalContext.WindowHandle, IMMContext);
// Ensure all known windows are associated with a disabled IME
ClearStaleWindowHandles();
for(const TWeakPtr<FGenericWindow>& Window : KnownWindows)
{
TSharedPtr<FGenericWindow> WindowPtr = Window.Pin();
if(WindowPtr.IsValid())
{
const HWND Hwnd = reinterpret_cast<HWND>(WindowPtr->GetOSWindowHandle());
if(Hwnd)
{
// TSF Implementation
ITfDocumentMgr* Unused;
if(FAILED(TSFThreadManager->AssociateFocus(Hwnd, TSFDisabledDocumentManager, &Unused)))
{
UE_LOG(LogWindowsTextInputMethodSystem, Error, TEXT("Deactivating a context failed while setting focus to the disabled TSF document manager."));
}
// IMM Implementation
::ImmAssociateContext(InternalContext.WindowHandle, nullptr);
}
}
}
// General Implementation
ActiveContext = nullptr;
UE_LOG(LogWindowsTextInputMethodSystem, Verbose, TEXT("Deactivated context %p!"), &(Context.Get()));
}