How to hold a object on two slides?

Question

I'm working on an animation of "Odd Magic Square" with Loubere Method.

But I can't hold the number "2" with dashed outline square on the two slides! How to?

The code:

    \documentclass[11pt]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usetheme{default}
%\usepackage{listings}
\usepackage{tikz}

\begin{document}



\begin{frame}{$n$- magic matrix} % ================================================================
\begin{itemize}[<+->]
\item text1
\item text2
\item text3
\end{itemize}

\begin{onlyenv}<+->
\begin{tikzpicture}
\tikzstyle{normal}=[fill=yellow!80!red]
\tikzstyle{testing}=[fill=yellow!80!red, fill opacity=0.4, dashed]
\tikzstyle{redarrow}=[->, thick, red]

\foreach \x in {0,1,2}
    \foreach \y in {0,1,2} {
        \draw[normal] (\x, \y) rectangle +(1, 1);
    }
\fill[fill opacity=0.1, fill=white] (-1, 3) rectangle +(1, 1);
\only<+->{
    \node at (1.5, 2.5) {$1$};
}
\only<+>{
    \draw[testing] (2, 3) rectangle +(1, 1);
    \node at (2.5, 3.5) {$2$};
}
\only<+>{
    \draw[redarrow] (2.5, 3.5) --(2.5, 0.8);    
}
\only<.->{
    \node at (2.5, 0.5) {$2$};
}
\only<+>{
    \draw[testing] (3, 1) rectangle +(1, 1);
    \node at (3.5, 1.5) {$3$};
}
\only<+>{
    \draw[redarrow] (3.5, 1.5) --(0.8, 1.5);    
}
\only<.->{
    \node at (0.5, 1.5) {$3$};
}
\only<+>{
    %\draw[fill=white] (1, 2) rectangle +(1, 1);
    \draw[fill=red!80!black, fill opacity=0.4, draw=red, dashed] (1, 2) rectangle +(1, 1);
    \node at (1.8, 2.2) {$4$};
}
\only<+->{
    \node at (0.5, 0.5) {$4$};
}
\end{tikzpicture}
\end{onlyenv}
\end{frame}
\end{document}

Answer 1

You can play with the overlay specification of only. See the code below.

\documentclass[11pt]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usetheme{default}
%\usepackage{listings}
\usepackage{tikz}

\begin{document}



\begin{frame}{$n$- magic matrix} % ================================================================
\begin{itemize}[<+->]
\item text1
\item text2
\item text3
\end{itemize}

\begin{onlyenv}<+->
\begin{tikzpicture}
\tikzstyle{normal}=[fill=yellow!80!red]
\tikzstyle{testing}=[fill=yellow!80!red, fill opacity=0.4, dashed]
\tikzstyle{redarrow}=[->, thick, red]

\foreach \x in {0,1,2}
    \foreach \y in {0,1,2} {
        \draw[normal] (\x, \y) rectangle +(1, 1);
    }
\fill[fill opacity=0.1, fill=white] (-1, 3) rectangle +(1, 1);
\only<+->{
    \node at (1.5, 2.5) {$1$};
}
\only<.-+>{
    \draw[testing] (2, 3) rectangle +(1, 1);
    \node at (2.5, 3.5) {$2$};
}
\only<.>{
    \draw[redarrow] (2.5, 3.5) --(2.5, 0.8);    
}
\only<.->{
    \node at (2.5, 0.5) {$2$};
}
\only<+>{}
\only<.-+>{
    \draw[testing] (3, 1) rectangle +(1, 1);
    \node at (3.5, 1.5) {$3$};
}
\only<.>{
    \draw[redarrow] (3.5, 1.5) --(0.8, 1.5);    
}
\only<.->{
    \node at (0.5, 1.5) {$3$};
}
\only<+>{
    %\draw[fill=white] (1, 2) rectangle +(1, 1);
    \draw[fill=red!80!black, fill opacity=0.4, draw=red, dashed] (1, 2) rectangle +(1, 1);
    \node at (1.8, 2.2) {$4$};
}
\only<+->{
    \node at (0.5, 0.5) {$4$};
}
\end{tikzpicture}
\end{onlyenv}
\end{frame}
\end{document}