Function MaybeBringWindowToFront

src/window.cpp:2504–2554

* Check if a window can be made relative top-most window, and if so do * it. If a window does not obscure any other windows, it will not * be brought to the foreground. Also if the only obscuring windows * are so-called system-windows, the window will not be moved. * The function will return false when a child window of this window is a * modal-popup; function returns a false and child window

 * @return false if the window has an active modal child, true otherwise
 */
static bool MaybeBringWindowToFront(Window *w)
{
	bool bring_to_front = false;

	if (w->window_class == WC_MAIN_WINDOW ||
			IsVitalWindow(w) ||
			w->window_class == WC_TOOLTIPS ||
			w->window_class == WC_DROPDOWN_MENU) {
		return true;
	}

	/* Use unshaded window size rather than current size for shaded windows. */
	int w_width  = w->width;
	int w_height = w->height;
	if (w->IsShaded()) {
		w_width  = w->unshaded_size.width;
		w_height = w->unshaded_size.height;
	}

	Window::IteratorToFront it(w);
	++it;
	for (; !it.IsEnd(); ++it) {
		Window *u = *it;
		/* A modal child will prevent the activation of the parent window */
		if (u->parent == w && u->window_desc.flags.Test(WindowDefaultFlag::Modal)) {
			u->SetWhiteBorder();
			u->SetDirty();
			return false;
		}

		if (u->window_class == WC_MAIN_WINDOW ||
				IsVitalWindow(u) ||
				u->window_class == WC_TOOLTIPS ||
				u->window_class == WC_DROPDOWN_MENU) {
			continue;
		}

		/* Window sizes don't interfere, leave z-order alone */
		if (w->left + w_width <= u->left ||
				u->left + u->width <= w->left ||
				w->top  + w_height <= u->top ||
				u->top + u->height <= w->top) {
			continue;
		}

		bring_to_front = true;
	}

	if (bring_to_front) BringWindowToFront(w);
	return true;
}

/**
 * Process keypress for editbox widget.