\documentclass[10pt,a4paper]{article}

% Packages
\usepackage{fancyhdr}           % For header and footer
\usepackage{multicol}           % Allows multicols in tables
\usepackage{tabularx}           % Intelligent column widths
\usepackage{tabulary}           % Used in header and footer
\usepackage{hhline}             % Border under tables
\usepackage{graphicx}           % For images
\usepackage{xcolor}             % For hex colours
%\usepackage[utf8x]{inputenc}    % For unicode character support
\usepackage[T1]{fontenc}        % Without this we get weird character replacements
\usepackage{colortbl}           % For coloured tables
\usepackage{setspace}           % For line height
\usepackage{lastpage}           % Needed for total page number
\usepackage{seqsplit}           % Splits long words.
%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
%\usepackage[english,german,french,spanish,italian]{babel}              % Languages

% Document Info
\author{mihdoc16}
\pdfinfo{
  /Title (mobile-application-1-2.pdf)
  /Creator (Cheatography)
  /Author (mihdoc16)
  /Subject (Mobile Application 1/2 Cheat Sheet)
}

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% the right line height in the tables
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% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
\newcommand{\mymulticolumn}[3]{\multicolumn{#1}{>{\columncolor{\RowColorName}}#2}{#3}} % For coloured multi-cols
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\newcommand{\tn}{\tabularnewline} % Required as custom column type in use

% Font and Colours
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\renewcommand{\familydefault}{\sfdefault}
\color{TextColor}

% Header and Footer
\pagestyle{fancy}
\fancyhead{} % Set header to blank
\fancyfoot{} % Set footer to blank
\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
    }
\end{tabulary}
\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Mobile Application 1/2 Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{mihdoc16} via \textcolor{DarkBackground}{\uline{cheatography.com/96249/cs/21903/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
  \SetRowColor{FootBackground}
  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}mihdoc16 \\
  \uline{cheatography.com/mihdoc16} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 4th March, 2020.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Sponsor}}  \\
  \SetRowColor{white}
  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{2}

\begin{tabularx}{8.4cm}{x{4 cm} x{4 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Explanation: Standard hello world app 1/2}}  \tn
% Row 0
\SetRowColor{LightBackground}
void main() =\textgreater{} runApp(MyApp()); & Main method which starts the class MyApp \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
class MyApp extends StatelessWidget \{...\} & creates class MyApp, the extend StatelessWidget makes the entire app into a widget \tn 
% Row Count 7 (+ 5)
% Row 2
\SetRowColor{LightBackground}
Widget build(BuildContext context) \{...\} & builds the widgets in this method \tn 
% Row Count 9 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{x{3.04 cm} x{4.96 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{8.4cm}}{\bf\textcolor{white}{Add external packages}}  \tn
% Row 0
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{8.4cm}}{The pubspec.yaml manages the assets and dependencies of a flutter app} \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
Example of pubspec.yaml: & `dependencies: 	flutter: 	      sdk: flutter 	    cupertino\_icons: \textasciicircum{}0.1.2 	    english\_words: \textasciicircum{}3.1.5` \tn 
% Row Count 7 (+ 5)
% Row 2
\SetRowColor{LightBackground}
Get packages: & At the top you should now be able to get the packages \tn 
% Row Count 10 (+ 3)
% Row 3
\SetRowColor{white}
\mymulticolumn{2}{x{8.4cm}}{After you get the packages there are free to be imported in whatever class you need} \tn 
% Row Count 12 (+ 2)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Create a List in flutter}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Widget \_buildSuggestions() \{ \newline   return ListView.builder( \newline       padding: const EdgeInsets.all(16.0), \newline       itemBuilder: /{\emph{1}}/ (context, i) \{ \newline         if (i.isOdd) return Divider(); /{\emph{2}}/       \newline         ==\textgreater{} {\bf{{\emph{The Divider adds visual seperation between two tiles of the list}}}} \newline  \newline         final index = i \textasciitilde{}/ 2; /{\emph{3}}/ \newline         if (index \textgreater{}= \_suggestions.length) \{ \newline           \seqsplit{\_suggestions.addAll(generateWordPairs().take(10));} /{\emph{4}}/ \newline         \} \newline         return \_buildRow(\_suggestions{[}index{]}); \newline       \}); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Mobile Application: Standard Hello World App 2/2}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{return MaterialApp(         {\bf{{\emph{returns an Material Design app}}}} \newline       title: 'Welcome to Flutter', \newline       home: Scaffold(         {\bf{{\emph{creates a Scaffold Widget}}}} \newline         appBar: AppBar(     {\bf{{\emph{creates an AppBar which contains a title}}}} \newline           title: Text('Welcome to Flutter'), \newline         ), \newline         body: Center(         {\bf{{\emph{creates a centered body with text in it}}}} \newline           child: Text('Hello World'), \newline         ), \newline       ), \newline     );} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Add a stateful widget}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{class RandomWords extends StatefulWidget \{ \newline   @override                                                                                               \newline   RandomWordsState createState() =\textgreater{} RandomWordsState(); \newline \} \newline ===\textgreater{} {\bf{{\emph{This widget just creates it's state class}}}} \newline  \newline class RandomWordsState extends State\textless{}RandomWords\textgreater{} \{ \newline   @override \newline   Widget build(BuildContext context) \{ \newline     final wordPair = WordPair.random(); \newline     return \seqsplit{Text(wordPair.asPascalCase);} \newline   \} \newline \} \newline ==\textgreater{} {\bf{{\emph{This class saves and creates new random words}}}}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{8.4cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{8.4cm}}{\bf\textcolor{white}{Build ListTile in Flutter with Interactivity}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{8.4cm}}{Widget \_buildRow(WordPair pair) \{ \newline   final alreadySaved = \_saved.contains(pair); \newline   return ListTile( \newline     title: Text(   ==\textgreater{} {\bf{{\emph{First Text is displayed in a tile}}}} \newline       pair.asPascalCase, \newline       style: \_biggerFont, \newline     ), \newline     trailing: Icon( ==\textgreater{} {\bf{{\emph{Adds an Icon to the tile}}}} \newline       alreadySaved ? Icons.favorite : Icons.favorite\_border, \newline       color: alreadySaved ? Colors.red : null, \newline     ), \newline     onTap: () \{     ==\textgreater{} {\bf{{\emph{Adds Interactivity to the tile}}}} \newline       setState(() \{ \newline         if (alreadySaved) \{ \newline           \_saved.remove(pair); \newline         \} else \{  \newline           \_saved.add(pair);  \newline         \}  \newline       \}); \newline     \},              \newline   ); \newline \}} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}