Function MakeLinkLabel

Telegram/SourceFiles/ui/boxes/boost_box.cpp:577–655

}

object_ptr<Ui::RpWidget> MakeLinkLabel(
		not_null<QWidget*> parent,
		rpl::producer<QString> text,
		rpl::producer<QString> link,
		std::shared_ptr<Ui::Show> show,
		object_ptr<Ui::RpWidget> right) {
	auto result = object_ptr<Ui::AbstractButton>(parent);
	const auto raw = result.data();

	const auto rawRight = right.release();
	if (rawRight) {
		rawRight->setParent(raw);
		rawRight->show();
	}

	struct State {
		State(
			not_null<QWidget*> parent,
			rpl::producer<QString> value,
			rpl::producer<QString> link)
		: text(std::move(value))
		, link(std::move(link))
		, label(parent, text.value(), st::giveawayGiftCodeLink)
		, bg(st::roundRadiusLarge, st::windowBgOver) {
		}

		rpl::variable<QString> text;
		rpl::variable<QString> link;
		Ui::FlatLabel label;
		Ui::RoundRect bg;
	};

	const auto state = raw->lifetime().make_state<State>(
		raw,
		rpl::duplicate(text),
		std::move(link));
	state->label.setSelectable(true);

	rpl::combine(
		raw->widthValue(),
		std::move(text)
	) | rpl::on_next([=](int outer, const auto&) {
		const auto textWidth = state->label.textMaxWidth();
		const auto skipLeft = st::giveawayGiftCodeLink.margin.left();
		const auto skipRight = rawRight
			? rawRight->width()
			: st::giveawayGiftCodeLink.margin.right();
		const auto available = outer - skipRight - skipLeft;
		const auto use = std::min(textWidth, available);
		state->label.resizeToWidth(use);
		const auto forCenter = (outer - use) / 2;
		const auto x = (forCenter < skipLeft)
			? skipLeft
			: (forCenter > outer - skipRight - use)
			? (outer - skipRight - use)
			: forCenter;
		state->label.moveToLeft(x, st::giveawayGiftCodeLink.margin.top());
	}, raw->lifetime());