答案utf8x 与 utf8 (输入)说utf8x一般不应该使用。但是listings，
\documentclass[12pt]{beamer}
\usepackage{ucs}
\usepackage[utf8]{inputenc}
\usepackage[T1,T2A]{fontenc}
\usepackage[russian]{babel}
\usepackage{color}
\usepackage{listings}
\lstset{
inputencoding=utf8,
extendedchars=\true,
literate={а}{{\selectfont\char224}}1
{б}{{\selectfont\char225}}1
{в}{{\selectfont\char226}}1
{г}{{\selectfont\char227}}1
{д}{{\selectfont\char228}}1
{е}{{\selectfont\char229}}1
{ё}{{\"e}}1
{ж}{{\selectfont\char230}}1
{з}{{\selectfont\char231}}1
{и}{{\selectfont\char232}}1
{й}{{\selectfont\char233}}1
{к}{{\selectfont\char234}}1
{л}{{\selectfont\char235}}1
{м}{{\selectfont\char236}}1
{н}{{\selectfont\char237}}1
{о}{{\selectfont\char238}}1
{п}{{\selectfont\char239}}1
{р}{{\selectfont\char240}}1
{с}{{\selectfont\char241}}1
{т}{{\selectfont\char242}}1
{у}{{\selectfont\char243}}1
{ф}{{\selectfont\char244}}1
{х}{{\selectfont\char245}}1
{ц}{{\selectfont\char246}}1
{ч}{{\selectfont\char247}}1
{ш}{{\selectfont\char248}}1
{щ}{{\selectfont\char249}}1
{ъ}{{\selectfont\char250}}1
{ы}{{\selectfont\char251}}1
{ь}{{\selectfont\char252}}1
{э}{{\selectfont\char253}}1
{ю}{{\selectfont\char254}}1
{я}{{\selectfont\char255}}1
{А}{{\selectfont\char192}}1
{Б}{{\selectfont\char193}}1
{В}{{\selectfont\char194}}1
{Г}{{\selectfont\char195}}1
{Д}{{\selectfont\char196}}1
{Е}{{\selectfont\char197}}1
{Ё}{{\"E}}1
{Ж}{{\selectfont\char198}}1
{З}{{\selectfont\char199}}1
{И}{{\selectfont\char200}}1
{Й}{{\selectfont\char201}}1
{К}{{\selectfont\char202}}1
{Л}{{\selectfont\char203}}1
{М}{{\selectfont\char204}}1
{Н}{{\selectfont\char205}}1
{О}{{\selectfont\char206}}1
{П}{{\selectfont\char207}}1
{Р}{{\selectfont\char208}}1
{С}{{\selectfont\char209}}1
{Т}{{\selectfont\char210}}1
{У}{{\selectfont\char211}}1
{Ф}{{\selectfont\char212}}1
{Х}{{\selectfont\char213}}1
{Ц}{{\selectfont\char214}}1
{Ч}{{\selectfont\char215}}1
{Ш}{{\selectfont\char216}}1
{Щ}{{\selectfont\char217}}1
{Ъ}{{\selectfont\char218}}1
{Ы}{{\selectfont\char219}}1
{Ь}{{\selectfont\char220}}1
{Э}{{\selectfont\char221}}1
{Ю}{{\selectfont\char222}}1
{Я}{{\selectfont\char223}}1
}
\begin{document}
\lstinline|а|
\end{document}
正常运行并显示西里尔文а。在两个位置替换utf8x为则显示。utf8Я
上面的literate“魔法咒语”（因为我不明白它是如何工作的）是否需要更改为utf8？
（我目前不想切换到 XeTeX。）
答案1
不管有没有 ucs，我都会得到错误的字符。问题是你使用\true而不是true作为选项extendedchars，因此实际上将其设置为 false。我还建议用命令等替换数字\cyra，你可以在 t2aenc.def 或 t2aend.dfu 中找到它们。
\documentclass[12pt]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1,T2A]{fontenc}
\usepackage[russian]{babel}
\usepackage{color}
\usepackage{listings}
\lstset{
inputencoding=utf8,
extendedchars=true, %compare with false instead
literate={а}{\cyra}1
{б}{{\selectfont\char225}}1
{в}{{\selectfont\char226}}1
{г}{{\selectfont\char227}}1
{д}{{\selectfont\char228}}1
{е}{{\selectfont\char229}}1
{ё}{{\"e}}1
{ж}{{\selectfont\char230}}1
{з}{{\selectfont\char231}}1
{и}{{\selectfont\char232}}1
{й}{{\selectfont\char233}}1
{к}{{\selectfont\char234}}1
{л}{{\selectfont\char235}}1
{м}{{\selectfont\char236}}1
{н}{{\selectfont\char237}}1
{о}{{\selectfont\char238}}1
{п}{{\selectfont\char239}}1
{р}{{\selectfont\char240}}1
{с}{{\selectfont\char241}}1
{т}{{\selectfont\char242}}1
{у}{{\selectfont\char243}}1
{ф}{{\selectfont\char244}}1
{х}{{\selectfont\char245}}1
{ц}{{\selectfont\char246}}1
{ч}{{\selectfont\char247}}1
{ш}{{\selectfont\char248}}1
{щ}{{\selectfont\char249}}1
{ъ}{{\selectfont\char250}}1
{ы}{{\selectfont\char251}}1
{ь}{{\selectfont\char252}}1
{э}{{\selectfont\char253}}1
{ю}{{\selectfont\char254}}1
{я}{{\selectfont\char255}}1
{А}{{\selectfont\char192}}1
{Б}{{\selectfont\char193}}1
{В}{{\selectfont\char194}}1
{Г}{{\selectfont\char195}}1
{Д}{{\selectfont\char196}}1
{Е}{{\selectfont\char197}}1
{Ё}{{\"E}}1
{Ж}{{\selectfont\char198}}1
{З}{{\selectfont\char199}}1
{И}{{\selectfont\char200}}1
{Й}{{\selectfont\char201}}1
{К}{{\selectfont\char202}}1
{Л}{{\selectfont\char203}}1
{М}{{\selectfont\char204}}1
{Н}{{\selectfont\char205}}1
{О}{{\selectfont\char206}}1
{П}{{\selectfont\char207}}1
{Р}{{\selectfont\char208}}1
{С}{{\selectfont\char209}}1
{Т}{{\selectfont\char210}}1
{У}{{\selectfont\char211}}1
{Ф}{{\selectfont\char212}}1
{Х}{{\selectfont\char213}}1
{Ц}{{\selectfont\char214}}1
{Ч}{{\selectfont\char215}}1
{Ш}{{\selectfont\char216}}1
{Щ}{{\selectfont\char217}}1
{Ъ}{{\selectfont\char218}}1
{Ы}{{\selectfont\char219}}1
{Ь}{{\selectfont\char220}}1
{Э}{{\selectfont\char221}}1
{Ю}{{\selectfont\char222}}1
{Я}{{\selectfont\char223}}1
}
\begin{document}
\lstinline|абЮ|
\end{document}
答案2
主要错误在于\true而不是true。
\documentclass[12pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1,T2A]{fontenc}
\usepackage[russian]{babel}
\usepackage{color}
\usepackage{listings}
\lstset{
inputencoding=utf8,
extendedchars=true,
literate=
{а}{{\cyra}}1
{б}{{\cyrb}}1
{в}{{\cyrv}}1
{г}{{\cyrg}}1
{д}{{\cyrd}}1
{е}{{\cyre}}1
{ё}{\"{\cyre}}1
{ж}{{\cyrzh}}1
{з}{{\cyrz}}1
{и}{{\cyri}}1
{й}{{\cyrishrt}}1
{к}{{\cyrk}}1
{л}{{\cyrl}}1
{м}{{\cyrm}}1
{н}{{\cyrn}}1
{о}{{\cyro}}1
{п}{{\cyrp}}1
{р}{{\cyrr}}1
{с}{{\cyrs}}1
{т}{{\cyrt}}1
{у}{{\cyru}}1
{ф}{{\cyrf}}1
{х}{{\cyrh}}1
{ц}{{\cyrc}}1
{ч}{{\cyrch}}1
{ш}{{\cyrsh}}1
{щ}{{\cyrshch}}1
{ъ}{{\cyrhrdsn}}1
{ы}{{\cyrery}}1
{ь}{{\cyrsftsn}}1
{э}{{\cyrerev}}1
{ю}{{\cyryu}}1
{я}{{\cyrya}}1
{А}{{\CYRA}}1
{Б}{{\CYRB}}1
{В}{{\CYRV}}1
{Г}{{\CYRG}}1
{Д}{{\CYR96}}1
{Е}{{\CYRE}}1
{Ё}{{\"{\CYRE}}}1
{Ж}{{\CYRZH}}1
{З}{{\CYRZ}}1
{И}{{\CYRI}}1
{Й}{{\CYRISHRT}}1
{К}{{\CYRK}}1
{Л}{{\CYRL}}1
{М}{{\CYRM}}1
{Н}{{\CYRN}}1
{О}{{\CYRO}}1
{П}{{\CYRP}}1
{Р}{{\CYRR}}1
{С}{{\CYRS}}1
{Т}{{\CYRT}}1
{У}{{\CYRU}}1
{Ф}{{\CYRF}}1
{Х}{{\CYRH}}1
{Ц}{{\CYRC}}1
{Ч}{{\CYRCH}}1
{Ш}{{\CYRSH}}1
{Щ}{{\CYRSHCH}}1
{Ъ}{{\CYRHRDSN}}1
{Ы}{{\CYRERY}}1
{Ь}{{\CYRSFTSN}}1
{Э}{{\CYREREV}}1
{Ю}{{\CYRYU}}1
{Я}{{\CYRYA}}1
}
\begin{document}
\lstinline|абвгдеёжз...юя|
\end{document}
