# Text alignment between columns (beamer)

I have a slide with two column in beamer, with overlays in both columns.

In the left column, I have a list of three items ; each item appears at each mouseclick/overlay and then stays on the screen.

In the right column, the content varies at each mouseclick/overlay along with the left column : at first and second times there are lists, and on the third one there is a figure.

My issue is that the content in the left column "moves" according to the content of the right column ; how can I fix this content at a particular place on the slide ?

Here is what my code looks like (It's the first time I'm using overlays, maybe it's a bit ugly, sorry) :

\begin{frame}{MyTitle}
\begin{columns}[t]
\begin{column}{6cm}
\begin{itemize}
\only<1-> { \item item 1 (left column, step 1)}
\only<2-> { \item item 2 (left column, step 2)}
\only<3-> { \item item 3 (left column, step 3)}
\end{itemize}
\end{column}
\begin{column}{6cm}
\only <1> {
\begin{itemize}
\item item 1 (right column, step 1)
\item item 2 (right column, step 1)
\item item 3 (right column, step 1)
\end{itemize}
}
\only<2> {
\begin{itemize}
\item (right column, step 2)
\item (right column, step 2)
\end{itemize}
}
\only<3> {
\begin{figure}
\centering
\includegraphics[scale=0.25]{left_column_step_3.png}
\end{figure}
}
\end{column}
\end{columns}
\end{frame}

• Maybe top aligning the frame would be an easy workaround: \begin{frame}[t] – user36296 Sep 6 '17 at 8:33
• Welcome to TeX.Stackexchange! – user36296 Sep 6 '17 at 8:33
• It works, thank you :). I can't believe I did not think about that – Micawber Sep 6 '17 at 8:58

A simple way to circumvent this problem is to use a top aligned frame:

\documentclass{beamer}

\begin{document}

\begin{frame}[t]{MyTitle}
\begin{columns}[t]
\begin{column}{.48\textwidth}
\begin{itemize}[<+->]
\item item 1 (left column, step 1)
\item item 2 (left column, step 2)
\item item 3 (left column, step 3)
\end{itemize}
\end{column}
\begin{column}{.48\textwidth}
\only<1>{
\begin{itemize}
\item item 1 (right column, step 1)
\item item 2 (right column, step 1)
\item item 3 (right column, step 1)
\end{itemize}
}
\only<2>{
\begin{itemize}
\item (right column, step 2)
\item (right column, step 2)
\end{itemize}
}
\includegraphics<3>[width=\textwidth]{example-image}
\end{column}
\end{columns}
\end{frame}

\end{document}