pgfplots：“顶部的轴”会划掉 ybar 值节点吗？

Question

假设我们有一个简单的ybar图表，其中包括ymajorgrids。

---

最小工作示例（MWE）：

\documentclass{standalone}
\usepackage{pgfplots}

\begin{document}
    \begin{tikzpicture}
        \begin{axis}[
                    ybar                    = 1.5mm,
                    ymin                    = 0,
                    ymax                    = 300,
                    set layers              = true,
                    axis on top             = true,
                    symbolic x coords       = {Blub, Blab, Blop},
                    ymajorgrids             = true,
                    nodes near coords,
                    nodes near coords align = {vertical},
                    nodes near coords style = {text=black},
                    every node near coord/.append style={rotate=90, anchor=west,font=\footnotesize},
                    ]
                \addplot coordinates {(Blab,180) (Blop,180) (Blub,180)};%
        \end{axis}
    \end{tikzpicture}
\end{document}

---

结果截图：

---

问题截图：

---

问题说明：

如您所见，该命令将导致占主导地位的值节点被axis on top划掉。我该如何避免节点被划掉（例如，将节点放在最顶层）？ybarymajorgrid

Answer 1

这个问题实际上比我想象的要复杂一些（或者我遗漏了一些基本的东西）。axis on top是某些特定层配置的简写，详细信息可参见部分4.27.2 使用预定义图层pgfplots 手册。对于许多目的，只需要更改图层的顺序，但据我所知，这并不能解决这个问题。我们能做什么？我查了一下nodes near coords（是的，有时简单的less /usr/local/texlive/2018/texmf-dist/tex/generic/pgfplots/pgfplots.code.tex操作有助于避免阅读手册 ;-)：它向发送特定指令scatter/@pre marker code。因此，我们只需通过附加scatter/@pre marker code，当然通过附加\pgfplotsonlayer{axis foreground}到来关闭末尾的图层。\endpgfplotsonlayercatter/@post marker code

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}
\begin{document}
    \begin{tikzpicture}
        \begin{axis}[clip mode=individual,
                    ybar                    = 1.5mm,
                    ymin                    = 0,
                    ymax                    = 300,
                    set layers              = true,
                    axis on top             = true,
                    symbolic x coords       = {Blub, Blab, Blop},
                    ymajorgrids             = true,
                    nodes near coords,
                    nodes near coords align = {vertical},
                    nodes near coords style = {text=black},
                    every node near coord/.append style={rotate=90, anchor=west,
                    font=\footnotesize},
                    scatter/@pre marker code/.append code={\pgfplotsonlayer{axis foreground}},
                    scatter/@post marker code/.append code={\endpgfplotsonlayer}
                    ]
                \addplot coordinates {(Blab,180) (Blop,180) (Blub,180)};%                
        \end{axis}
    \end{tikzpicture}
\end{document}

如您所见，网格线位于条形图的前面但在后面nodes near coords。

至于您在评论中提出的问题：

是否有一个选项可以让网格保持在后台，而只将横坐标和纵坐标移动到前台？

axis on top当然，这容易多了。我所做的就是从 pgfplots 手册第 410 页复制图层排序处方，然后交换axis grid和main（并为该排序命名并将其安装在图中）。这样，您可以实现任何排序（除了 coords 附近的节点，您可以按照上面讨论的方式处理它们）。

\documentclass{standalone}
\usepackage{pgfplots}
\pgfplotsset{compat=1.16}
\pgfplotsset{ % define your layer ordering
    /pgfplots/layers/axis a la Dave/.define layer set={
        axis background,axis grid,main,axis ticks,axis lines,axis tick labels,
        axis descriptions,axis foreground
    }{/pgfplots/layers/standard},
}
\begin{document}
    \begin{tikzpicture}
        \begin{axis}[clip mode=individual,
                    ybar                    = 1.5mm,
                    ymin                    = 0,
                    ymax                    = 300,
                    set layers              = true,
                    set layers=axis a la Dave, % <install your layer ordering
                    grid style={/pgfplots/on layer=axis background},
                    symbolic x coords       = {Blub, Blab, Blop},
                    ymajorgrids             = true,
                    nodes near coords,
                    nodes near coords align = {vertical},
                    nodes near coords style = {text=black},
                    every node near coord/.append style={rotate=90, anchor=west,
                    font=\footnotesize},
                    ]
                \addplot coordinates {(Blab,180) (Blop,180) (Blub,180)};%                
        \end{axis}
    \end{tikzpicture}
\end{document}