答案1
欢迎来到 TeX.SE!我不认为我会为此使用任何 GUI。
\documentclass[tikz,border=3.14mm]{standalone}
\begin{document}
\begin{tikzpicture}
\node[draw,thick,minimum width=1cm,minimum height=0.4cm,outer sep=4pt] at (0,0) (A) {};
\node[draw,thick,minimum width=1cm,minimum height=0.4cm,outer sep=4pt] at (6,0) (B) {};
\draw[thick] (A.north) -- (A.south) node[below] {$t_\mathrm{initial}$};
\draw[thick] (B.north) -- (B.south) node[below] {$t_\mathrm{final}$};
\draw[thick,latex-latex] ([yshift=4pt]A.north west) -- ([yshift=4pt]A.north
east);
\draw[thick,latex-latex] ([yshift=4pt]B.north west) -- ([yshift=4pt]B.north
east);
\draw[thick] (A.center) -- (B.center);
\end{tikzpicture}
\end{document}