How to make a textbox with this TikZ code ?

Question

I made this with TikZ :

\usetikzlibrary{calc}
\def\banlen{3}
\xdefinecolor{mycolor}{RGB}{62,96,111} % Neutral Blue
\def\bancolor{mycolor}
\begin{tikzpicture}
\draw (0.25,0.25) rectangle (5,-2); %
\fill[\bancolor](0,0) -- (0.25,-0.25) -- (0.25,0); % Coin bas-gauche
\fill[\bancolor](\banlen,0.5) -- (\banlen-0.25,0.75) -- (\banlen-0.25,0.5); %Coin haut-droit
\fill[\bancolor!75] (0,0) rectangle (\banlen,0.5); % Rectangle (banner)
\draw (\banlen/2,0.25) node {Box name};
\end{tikzpicture}

How to add text in, adjust the banlen value with the Boxname text and adjust the box size ? And how to make a environment with a color parameter ?

I have some difficult with the coordinates :s

Thanks.

Answer 1

I would recommend to use nodes and their coordinates to draw the lines and not to do this manually. TikZ allows you to write \node \bgroup .. \egroup; instead of \node { .. }; and therefore you can wrap a node and the whole tikzpicture around the content of an environment. If you use font size specific units, i.e. ex and em, the whole box will scale nicely with the font size:

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{calc}

\xdefinecolor{mycolor}{RGB}{62,96,111} % Neutral Blue
\colorlet{bancolor}{mycolor}

\def\bancolor{mycolor}
\newenvironment{mybox}[3][]{%
    \begin{tikzpicture}[#1]%
        \def\myboxname{#3}%
        \node [draw,inner sep=1.5ex,text width=#2]% good options: minimum height, minimum width
            (BOXCONTENT) \bgroup\rule{0pt}{3ex}\ignorespaces
}{%
        \egroup;
        \node [right,inner xsep=1em,fill=bancolor!75,outer sep=0pt,text height=2ex,text depth=.5ex] (BOXNAME) 
            at ([shift={(-1em,0pt)}]BOXCONTENT.north west) {\myboxname};
        \fill[bancolor] (BOXNAME.north east) -- +(-1em,1em) -- +(-1em,0) -- cycle;
        \fill[bancolor] (BOXNAME.south west) -- +(1em,-1em) -- +(1em,0) -- cycle;
    \end{tikzpicture}
}

\begin{document}

\begin{mybox}{10em}{Test}
    This is the content
\end{mybox}

\begin{mybox}{15em}{Test it really good}
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
\end{mybox}

\huge

\begin{mybox}{10em}{Test}
    This is the content
\end{mybox}

\begin{mybox}{15em}{Test it really good}
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
\end{mybox}
\tiny

\begin{mybox}{10em}{Test}
    This is the content
\end{mybox}

\begin{mybox}{15em}{Test it really good}
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
    This is the longer content
\end{mybox}


\end{document}

Answer 2

tcolorbox is a good tool for this kind of boxes. It uses TiKZ as drawing engine and with its recent versions is easier to compound boxes with detached titles like this one. Some examples follow:

\documentclass{article}
\usepackage[most]{tcolorbox}
\usepackage{varwidth}
\usepackage{lipsum}

\definecolor{bancolor}{RGB}{62,96,111}

\tcbset{myboxstyle/.style={enhanced,skin=enhanced jigsaw,
attach boxed title to top left={xshift=-3mm,yshift=-\tcboxedtitleheight/2},
coltitle=black,varwidth boxed title=0.7\linewidth,
colbacktitle=#1!75, colback=white,sharp corners,
top=2ex,
boxed title style={sharp corners, boxrule=0pt},
underlay boxed title={
\fill[#1] (title.south west) -- (title.south-|frame.west)--++(0,-.5*\tcboxedtitleheight)--cycle;
\fill[#1] (title.north east) --++(-.5*\tcboxedtitleheight,0)--++(0,.5*\tcboxedtitleheight)--cycle;}},
    myboxstyle/.default=bancolor}


\newtcolorbox{mybox}[2][]{myboxstyle,
title={\hspace*{.5cm}#2\hspace*{.5cm}},#1}

\begin{document}
\begin{mybox}{My Title}
\lipsum[1]
\end{mybox}

\begin{mybox}[width=.5\linewidth]{My Title}
A short text
\end{mybox}

\tcbox[myboxstyle=red,title=My title]{A short box}
\end{document}