添加 tikz 箭头后对侧边标题进行水平调整

Question

我有一个带侧边标题的图，我在图片上添加了一个箭头，但现在自从我添加了箭头后，所有内容都不再居中了，有没有办法强制居中以适应我使用 tikz 添加的箭头？谢谢您的宝贵时间。

\documentclass[a4paper, twoside, 12pt]{report}
\usepackage[a4paper,showframe,width=150mm,top=25mm,bottom=25mm]{geometry}
\usepackage{subcaption}
\usepackage{floatrow}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows,backgrounds}

\begin{document}
\begin{figure}[h!]
\begin{tikzpicture}
\useasboundingbox (0,0);
    \node[single arrow,draw=black,fill=black,minimum height=4.8cm, rotate=270] at (3.8,-2.8) {};
\end{tikzpicture}
\floatbox[{\capbeside\thisfloatsetup{capbesideposition={left,top},capbesidewidth=4cm}}]{figure}[\FBwidth]{\caption{caption here}}{\includegraphics[scale=0.32]{SizeExChrom}}

\end{figure}
\end{document}

Answer 1

当前代码的问题在于，由于您使用了\useasboundingbox (0,0);

为了更好地控制箭头的定位，我建议您将图像也包含在内\node并tikzpicture保留自然边界框，这样居中时就会考虑适当的宽度。另一个优点是，现在，借助库calc，您可以让 TikZ 计算箭头的高度：

代码：

\documentclass[a4paper, twoside, 12pt]{report}
\usepackage[a4paper,showframe,width=150mm,top=25mm,bottom=25mm]{geometry}
\usepackage{subcaption}
\usepackage{floatrow}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows,backgrounds,calc}

\begin{document}
\begin{figure}
\floatbox[{\capbeside\thisfloatsetup{capbesideposition={left,top},capbesidewidth=4cm}}]{figure}[\FBwidth]{\caption{caption here}}{%
\begin{tikzpicture}
\node[anchor=south east,inner sep=0pt] (image)
  {\includegraphics[width=6cm,height=7cm]{example-image-a}};
\path
  let
  \p1=(image.north),
  \p2=(image.south)
  in
  node[
    single arrow,
    draw=black,
    fill=black,
    minimum height=\y1-\y2,
    rotate=270
    ] 
    at ([shift={(20pt,0pt)}]image.east) {};
\end{tikzpicture}%
}
\end{figure}
\end{document}

附注：不要使用[!h]浮点位置说明符，因为它的限制性太强，很容易导致灾难；要么使用限制性较小的说明符，要么根本不使用。

Answer 2

这是您想要实现的吗（或多或少）？

\documentclass[a4paper, twoside, 12pt]{report}
\usepackage[a4paper,showframe,width=150mm,top=25mm,bottom=25mm]{geometry}
\usepackage{subcaption}
\usepackage{floatrow}
\usepackage{tikz}
\usetikzlibrary{shapes,arrows,backgrounds}

\begin{document}
\begin{figure}[h!]
\floatbox[{\capbeside\thisfloatsetup{capbesideposition={left,top},capbesidewidth=4cm}}]{figure}[\FBwidth]{\caption{caption here}}%
{\includegraphics[height=4.8cm]{example-image}\begin{tikzpicture}
%\useasboundingbox (0,0);
    \node[single arrow,draw=black,fill=black,minimum height=4.8cm, rotate=270] at (3.8,-2.8) {};
\end{tikzpicture}}

\end{figure}
\end{document}