How to create the following figures in TikZ

Question

I'd like to create the following two figures with TikZ

I'm tikz beginner, can anybody give me some advice how to do that?

Now i've created the first figure:

\documentclass[border=5pt]{standalone}
\usepackage[utf8]{inputenc}
\usepackage{tikz}
\usetikzlibrary{matrix, positioning, fit}
\begin{document}
\begin{tikzpicture}[
  mymatrix/.style={matrix of nodes, nodes=typetag, row sep=1em, anchor=base},
  mycontainer/.style={draw=black,inner sep=1ex},
  typetag/.style={draw=black, inner sep=1ex, anchor=west},
  title/.style={draw=none, color=black, inner sep=0pt}
  ]
  \matrix[mymatrix] (mx1) {
    |[title]|Text A \\
    Text 1 \\
    Text 2 \\
    Text 3 \\
    Text 4 \\
    Text 5 \\
    Text 6 \\
  };
  \matrix[mymatrix, right=of mx1.north east, matrix anchor=north west] (mx2) {
    |[title]|Text D \\
    Text 13 \\
    Text 14 \\
    Text 15 \\
    Text 16 \\
    Text 17 \\
    Text 18 \\
  };
  \matrix[mymatrix, right=of mx2.north east, matrix anchor=north west] (mx3) {
    |[title]|Text E \\
    Text 19 \\
  };
  \matrix[mymatrix, above=of mx2.north, matrix anchor=south west] (mx4) {
    |[title]|Text C \\
    Text 12 \\
  };
  \matrix[mymatrix, above=of mx2.north, matrix anchor=south east] (mx5) {
    |[title]|Text B \\
    Text 7 \\
    Text 8 \\
    Text 9 \\
    Text 10 \\
    Text 11 \\
  };

  \node[mycontainer, fit=(mx1)] (n1) {};
  \node[mycontainer, fit=(mx2)] (n2) {};
  \node[mycontainer, fit=(mx3)] (n3) {};
  \node[mycontainer, fit=(mx4)] (n4) {};
  \node[mycontainer, fit=(mx5)] (n5) {};

  \path[->,thick] (n1) edge (n2);
  \path[->,thick] (n3) edge (n2);
  \path[->,thick] (n4) edge (n2);
  \path[->,thick] (n5) edge (n2);
\end{tikzpicture}
\end{document}

As already mentioned I'm a TikZ beginner, so there are the following problems:

1. How can the boxes around "Text 1", "Text 2" and so on have the same width and height? I'd like to have them centered, too.
2. How can I create the arrows look like in the sample picture? Actually they seem badly arranged.
3. How can I create the black boxes like in the sample picture?
4. Is it the right way to use matrix to create this figure, could it be done easier?

Here is the LaTeX-code for the second figure:

\documentclass[tikz,border=5pt]{standalone}
\usepackage[ngerman]{babel}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[utf8]{inputenc}
%
\usepackage{tikz}
\usetikzlibrary{matrix,positioning-plus}


\begin{document}
\begin{tikzpicture}[
kreis/.style={circle,draw,minimum width=20pt},
every node/.style={align=center}]

\matrix(mat)[row sep=10pt, column sep=60pt] at (0,0) {
\node[kreis](k1) {}; &
\node[kreis](k2) {}; &
\node[kreis](k3) {}; &
\node[kreis](k4) {}; &
\node[kreis](k5) {}; &
\node[kreis](k6) {}; \\
};

 \draw[-latex] (k1) -- (k2);
 \draw[-latex] (k2) -- (k3);
 \draw[-latex] (k3) -- (k4);
 \draw[-latex] (k4) -- (k5);
 \draw[-latex] (k5) -- (k6);

\node [below,text width=2.5cm,font=\small] at (k1.south) {Text 1};
\node [below,text width=2.5cm,font=\small] at (k2.south) {Text 2};
\node [below,text width=2.5cm,font=\small] at (k3.south) {Text 3};
\node [below,text width=2.5cm,font=\small] at (k4.south) {Text 4};
\node [below,text width=2.5cm,font=\small] at (k5.south) {Text 5};
\node [below,text width=2.5cm,font=\small] at (k6.south) {Text 6};

\node (n1) [above=of k1] {};
\node (n2) [above=of k2] {};
\node (n3) [above=of k3] {};
\node (n4) [above=of k4] {};
\node (n5) [above=of k5] {};
\node (n6) [above=of k6] {};


 \draw[latex-latex] (n1) -- (n2) node[midway,above] {Text 7};
 \draw[latex-latex] (n2) -- (n3) node[midway,above] {Text 8};
 \draw[latex-latex] (n3) -- (n4) node[midway,above] {Text 9};
 \draw[latex-latex] (n4) -- (n5) node[midway,above] {Text 10};
 \draw[latex-latex] (n5) -- (n6) node[midway,above] {Text 11};

\node (m1) [above=of n1] {};
\node (m5) [above=of n5] {};
\node (m6) [above=of n6] {};


 \draw[latex-latex] (m1) -- (m5) node[midway,above] {Text 12};
 \draw[latex-latex] (m5) -- (m6) node[midway,above] {Text 13};

\node (k1) [above=of m1] {};
\node (k6) [above=of m6] {};

 \draw[latex-latex] (k1) -- (k6) node[midway,above] {Text 14};

\end{tikzpicture}
\end{document}

Actually I have the following problems with it:

1. The arrows above the circles are to short, how can I adjust them?
2. The text above the arrows is not vertically centered, what can I do here?
3. How can I add vertical lines like in the picture above?

Another Question belongs to posting, how can I quickly generate and present a picture of my code?

Answer 1

For the first problem, nodes having the same size, see Dependent node size in TikZ (which solution I am going to use) and the linked questions which comes down to identifying the widest/tallest/deepest element and giving its measurements as options to the nodes (see text width, text height and text depth). I am using the ext.node-families library from the linked question/answer.

The second problem, better connections between the matrices I am going to use the keys only horizontal first and only vertical first from the ext.paths.ortho library which got developed for another Antwort von mir.
These are similar to the path operations -| and |- but don't draw the second part. An optional argument shifts the resulting line orthogonally to its direction.

Your fourth point, regarding the use of matrices, I think that this is a good example to use matrices, even though we only have one column per matrix. For more complicated stuff and maybe even the matrices with the bold black border, one can use a combination of the fit and the backgrounds library. For examples see my answers [1] and [2].

Now, the black borders will require work. I am using here a solution that first places the fully filled node (“Longer Text D” and “Text E”), and then adds a matrix directly below it which both are then fitted with a node that is only used for the drawn line around it.

There are many different approaches possible for this problem. It is our advantage that these problematic matrices are only placed in the lower row of all matrices and only to the right of other matrices. Note the xshift and yshift in the Title style. If you want to place it to the left, you need to use a negative yshift value (well, at least if you want to use the “correct” node distance). If you want to place such matrices above other nodes/matrices, you better first place the matrix part of this structure (then with a positive yshift for correction of the black border) and then the Title above it (but then without any shifting values).

The ext.positioning-plus library adds another set of …=of … keys to the positioning library (and also loads fit). This introduces the north right=of <ref-node> key that basically is the same as right=of <ref-node>.north east, anchor=north west.

This library also allows us to use x_node_dist and y_node_dist as a reference to the node distances that is set with the node distance key.

---

All mentioned libraries starting with ext. are part of my tikz-ext package.

Code

\documentclass[tikz,border=5pt]{standalone}
\usepackage{tikz}
\usetikzlibrary{
  arrows.meta,          % for proper arrows
  matrix,               % for “matrix of nodes”
  ext.positioning-plus, % for “x/y_node_dist”, “north right=of …”
  ext.node-families,    % for “node family/width”
  ext.paths.ortho       % for “only vertical first”
}
\tikzset{
  fitty line width/.initial=.25cm,
  fitty/.style={
    fit=(#1')(#1''),
    line width=\pgfkeysvalueof{/tikz/fitty line width},
    inner sep=\pgfkeysvalueof{/tikz/fitty line width}/2,
    draw, name=#1},
}
\begin{document}
\begin{tikzpicture}[
  my matrix*/.style={
    nodes={inner sep=+1em, typetag, node family/width=m, text depth=+0pt},
    matrix of nodes, row sep=+.5em, node family/width=M},
  my matrix/.style={
    my matrix*, draw, row 1/.append style={nodes=title}},
  title/.style={draw=none, node font=\bfseries},
  Title/.default=-+, % use different signs for different placements
  Title/.style 2 args={
    title, draw, node family/width=M,
    fill, text=white, text depth=+0pt, inner ysep=.5em, outer sep=+0pt,
    yshift=(\pgfkeysvalueof{/tikz/fitty line width})*#11,
    xshift=(\pgfkeysvalueof{/tikz/fitty line width})*#21},
  typetag/.style={draw=black, inner sep=1ex, align=center},
  >=Latex
]
\matrix[my matrix] (mx1) {
    Text A \
    Text 1 \
    Text 2 \
    Text 3 \
    Text 4 \
    Text 5 \
    Text 6 \
  };
% Title makes sure the extra thick line around everything is taken
  % into account, i.e. the node needs to be shifted a bit more
  \node[Title, north right=of mx1]       (mx2')  {Longer Text D};
  \matrix[my matrix, below=+0pt of mx2'] (mx2'') {
    Text ABC\
    Text 13 \
    Text 14 \
    Text 15 \
    Text 16 \
    Text 17 \
    Text 18 \
  };
  \node[fitty=mx2]{}; % the thick black box around it
\node[Title, north right=of mx2]        (mx3')  {Text E};
  \matrix[my matrix*, below=+0pt of mx3'] (mx3'') {Text 19 \};
  \node[fitty=mx3] {};
\matrix[my matrix,
    above=of mx2.north,
    matrix anchor=south east, xshift=-.5*x_node_dist] (mx5) {
    Text B  \
    Text 7  \
    Text 8  \
    Text 9  \
    Text 10 \
    Text 11 \
  };
  \matrix[my matrix, north right=of mx5] (mx4) {
    Text C  \
    Text 12 \
  };
\path [thick, ->]
    [only horizontal first=-y_node_dist] 
      (mx1.north east) edge (mx2)
      (mx3.north west) edge (mx2)
    (mx5.south east) edge[only vertical first=-x_node_dist] (mx2)
    (mx4.south west) edge[only vertical first= x_node_dist] (mx2);
\end{tikzpicture}
\end{document}

Output

Answer 2

Since you already have the two PDF files (fig_process and fig_steps), it is very easy:

\documentclass[tikz]{standalone}
\begin{document}
\begin{tikzpicture}
  \node[inner sep=0] {\includegraphics{fig_process}};
\end{tikzpicture}
\begin{tikzpicture}
  \node[inner sep=0] {\includegraphics{fig_steps}};
\end{tikzpicture}
\end{document}