Method prepare

Telegram/SourceFiles/dialogs/ui/dialogs_topics_view.cpp:49–114

}

void TopicsView::prepare(MsgId frontRootId, Fn<void()> customEmojiRepaint) {
	Expects(_forum != nullptr);

	const auto &list = _forum->recentTopics();
	_version = _forum->recentTopicsListVersion();
	_titles.reserve(list.size());
	auto index = 0;
	for (const auto &topic : list) {
		const auto from = begin(_titles) + index;
		const auto key = topic->rootId().bare;
		const auto i = ranges::find(
			from,
			end(_titles),
			key,
			&Title::key);
		if (i != end(_titles)) {
			if (i != from) {
				ranges::rotate(from, i, i + 1);
			}
		} else if (index >= _titles.size()) {
			_titles.emplace_back();
		}
		auto &title = _titles[index++];
		const auto unread = topic->chatListBadgesState().unread;
		if (title.key == key
			&& title.unread == unread
			&& title.version == topic->titleVersion()) {
			continue;
		}
		const auto context = Core::TextContext({
			.session = &topic->session(),
			.repaint = customEmojiRepaint,
			.customEmojiLoopLimit = kIconLoopCount,
		});
		auto topicTitle = topic->titleWithIcon();
		title.key = key;
		title.version = topic->titleVersion();
		title.unread = unread;
		title.title.setMarkedText(
			st::dialogsTextStyle,
			(unread
				? Ui::Text::Colorized(
					Ui::Text::Wrapped(
						std::move(topicTitle),
						EntityType::Bold))
				: std::move(topicTitle)),
			DialogTextOptions(),
			context);
	}
	while (_titles.size() > index) {
		_titles.pop_back();
	}
	const auto i = frontRootId
		? ranges::find(_titles, frontRootId.bare, &Title::key)
		: end(_titles);
	_jumpToTopic = (i != end(_titles));
	if (_jumpToTopic) {
		if (i != begin(_titles)) {