Method handleKeyInputEvent

pcsx2-qt/DisplayWidget.cpp:225–283

Keyboard focus and child windows are inconsistant across platforms; Windows: Can programmatically focus the child window, NVidia overlay can defocus it. X11: Can programmatically focus the child window. Wayland: Child window cannot be focused at all on most(?) DE. Mac: Can programmatically focus the child window. Thus for KB inputs we need to sometimes use the event filter. Mouse events are always

// Thus for KB inputs we need to sometimes use the event filter.
// Mouse events are always delivered to the child window, so that seems consistant.
void DisplaySurface::handleKeyInputEvent(QEvent* event)
{
	switch (event->type())
	{
		case QEvent::KeyPress:
		case QEvent::KeyRelease:
		{
			const QKeyEvent* key_event = static_cast<QKeyEvent*>(event);

			// Forward text input to imgui.
			if (ImGuiManager::WantsTextInput() && key_event->type() == QEvent::KeyPress)
			{
				// Don't forward backspace characters. We send the backspace as a normal key event,
				// so if we send the character too, it double-deletes.
				QString text(key_event->text());
				text.remove(QChar('\b'));
				if (!text.isEmpty())
					ImGuiManager::AddTextInput(text.toStdString());
			}

			if (key_event->isAutoRepeat())
				return;

			// For some reason, Windows sends "fake" key events.
			// Scenario: Press shift, press F1, release shift, release F1.
			// Events: Shift=Pressed, F1=Pressed, Shift=Released, **F1=Pressed**, F1=Released.
			// To work around this, we keep track of keys pressed with modifiers in a list, and
			// discard the press event when it's been previously activated. It's pretty gross,
			// but I can't think of a better way of handling it, and there doesn't appear to be
			// any window flag which changes this behavior that I can see.

			const u32 key = QtUtils::KeyEventToCode(key_event);
			const Qt::KeyboardModifiers modifiers = key_event->modifiers();
			const bool pressed = (key_event->type() == QEvent::KeyPress);
			const auto it = std::find(m_keys_pressed_with_modifiers.begin(), m_keys_pressed_with_modifiers.end(), key);
			if (it != m_keys_pressed_with_modifiers.end())
			{
				if (pressed)
					return;
				else
					m_keys_pressed_with_modifiers.erase(it);
			}
			else if (modifiers != Qt::NoModifier && modifiers != Qt::KeypadModifier && pressed)
			{
				m_keys_pressed_with_modifiers.push_back(key);
			}

			Host::RunOnCPUThread([key, pressed]() {
				InputManager::InvokeEvents(InputManager::MakeHostKeyboardKey(key), static_cast<float>(pressed));
			});

			return;
		}

		default:
			pxAssert(false);
			return;
	}