tikz：绘制箭头到下方矩形中间上方

Question

如何将箭头从矩形 R2 中间正上方移到 R2.north（顶部中心）？

\documentclass[a4paper]{scrartcl}
\usepackage{amsmath,amssymb,amsfonts}
\usepackage{tikz}
\usepackage{tikz-uml}
\usetikzlibrary{shapes.multipart,positioning,fit}
\usepackage{pgf-umlsd}
\usetikzlibrary{arrows}

    \begin{document}
    \begin{tikzpicture}
        \node[text width=3cm]                       (A)  at (0,0)               {\tiny AAA};
        
        \node[anchor=north west , text width=1cm]   (A1) at (A.south west)      {\tiny BBB};
        \node[anchor=west       , text width=1cm]   (A2) at (A1.east)           {\tiny CCC};
        \node[anchor=west       , text width=1cm]   (A3) at (A2.east)           {\tiny DDD};
        
        \node[anchor=north west , text width=1cm]   (A4) at (A1.south west)     {\tiny EEE};
        \node[anchor=west       , text width=1cm]   (A5) at (A4.east)           {\tiny FFF};
        \node[anchor=west       , text width=1cm]   (A6) at (A5.east)           {\tiny };
        
        \node [inner sep=0pt,
        draw,
        rounded corners,
        fit = (A)(A1)(A2)(A3)(A4)(A5)(A6)
        ] (A13) {}; 
        
        \draw   (A1.north west) -- (A3.north east)
        (A1.south west) -- (A3.south east);    
        
        \node[below left = 1.0cm and 0.5cm of A13.south, text width=1cm]    (B1) {\tiny GGG};
        \node[below =0cm of B1, text width=1cm] (B2) {\tiny HHH};
        \node [inner sep=0pt,
        draw,
        rounded corners,
        fit = (B1)(B2)
        ] (B6) {}; 
        
        \draw[gray,->] (A6.center)  -- ++(east:1.0) -- ++(down:0.5) -- ++(west:1.5) -- ++(down:0.4);
        
    \end{tikzpicture}
    \end{document} 

Answer 1

为此，您可以使用-|连接器，它（与--仅绘制连接两个节点的直线不同）先绘制一条水平线，然后绘制一条垂直线，以便两个节点以直角连接。还有一种对应物|-首先绘制垂直线。然后，您可以使用 轻松让箭头结束在正上方B6（这就是您在代码中命名您在图片中用 R2 表示的节点的方式）B6.north。

完整的代码将是（我注释掉了两个不需要的包，而且我也没有第一个包）：

\documentclass[a4paper]{scrartcl}
\usepackage{amsmath,amssymb,amsfonts}
\usepackage{tikz}
%\usepackage{tikz-uml}
\usetikzlibrary{shapes.multipart,positioning,fit}
%\usepackage{pgf-umlsd}
\usetikzlibrary{arrows}

\begin{document}
    \begin{tikzpicture}
        \node[text width=3cm]                       (A)  at (0,0)               {\tiny AAA};
        
        \node[anchor=north west , text width=1cm]   (A1) at (A.south west)      {\tiny BBB};
        \node[anchor=west       , text width=1cm]   (A2) at (A1.east)           {\tiny CCC};
        \node[anchor=west       , text width=1cm]   (A3) at (A2.east)           {\tiny DDD};
        
        \node[anchor=north west , text width=1cm]   (A4) at (A1.south west)     {\tiny EEE};
        \node[anchor=west       , text width=1cm]   (A5) at (A4.east)           {\tiny FFF};
        \node[anchor=west       , text width=1cm]   (A6) at (A5.east)           {\tiny };
        
        \node [inner sep=0pt,
        draw,
        rounded corners,
        fit = (A)(A1)(A2)(A3)(A4)(A5)(A6)
        ] (A13) {}; 
        
        \draw   (A1.north west) -- (A3.north east)
        (A1.south west) -- (A3.south east);    
        
        \node[below left = 1.0cm and 0.5cm of A13.south, text width=1cm]    (B1) {\tiny GGG};
        \node[below =0cm of B1, text width=1cm] (B2) {\tiny HHH};
        \node [inner sep=0pt,
        draw,
        rounded corners,
        fit = (B1)(B2)
        ] (B6) {}; 
        
        \draw[gray,->] (A6.center)  -- ++(east:1.0) -- ++(down:0.5) -- ++(west:1.5) -| (B6.north);
        
    \end{tikzpicture}
\end{document}