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%\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
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% Document Info
\author{{[}deleted{]}}
\pdfinfo{
  /Title (adding-push-notifications-to-a-web-app.pdf)
  /Creator (Cheatography)
  /Author ({[}deleted{]})
  /Subject (Adding Push Notifications to a Web App Cheat Sheet)
}

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% Header and Footer
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\fancyhead{} % Set header to blank
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\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}}
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\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Adding Push Notifications to a Web App Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{{[}deleted{]}} via \textcolor{DarkBackground}{\uline{cheatography.com/96251/cs/21633/}}}
\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}{[}deleted{]} \\
  \uline{cheatography.com/deleted-96251} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Published 21st January, 2020.\\
   Updated 22nd January, 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*}{3}

\begin{tabularx}{5.377cm}{x{2.18988 cm} x{2.78712 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Setup}}  \tn
% Row 0
\SetRowColor{LightBackground}
Clone repo & git clone \seqsplit{https://github.com/GoogleChrome/push-notifications.git} \tn 
% Row Count 3 (+ 3)
% Row 1
\SetRowColor{white}
Install webserver & \seqsplit{https://chrome.google.com/webstore/detail/web-server-for-chrome/ofhbbkphhbklhfoeikjpcbhemlocgigb} \tn 
% Row Count 8 (+ 5)
% Row 2
\SetRowColor{LightBackground}
\mymulticolumn{2}{x{5.377cm}}{Select app folder from cloned repo in webserver} \tn 
% Row Count 9 (+ 1)
% Row 3
\SetRowColor{white}
Always update the service worker & Open DevTools (Right Click \textgreater{} Inspect) -\textgreater{} Application -\textgreater{} Service Workers -\textgreater{} Update on Reload \tn 
% Row Count 14 (+ 5)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Register a Service Worker}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\seqsplit{navigator.serviceWorker.register('sw.js')}   .then(function(swReg) \{     console.log('Service Worker is registered', swReg);      swRegistration = swReg;   \})} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Subscribe the user}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\seqsplit{swRegistration.pushManager.getSubscription()} \newline   \seqsplit{.then(function(subscription)} \{ \newline     isSubscribed = !(subscription === null); \newline  \newline     \seqsplit{updateSubscriptionOnServer(subscription);} \newline  \newline  const applicationServerKey = \seqsplit{urlB64ToUint8Array(applicationServerPublicKey);} \newline   \seqsplit{swRegistration.pushManager}.subscribe(\{ \newline     userVisibleOnly: true, \newline     applicationServerKey: applicationServerKey \newline   \}) \newline   \seqsplit{.then(function(subscription)} \{ \newline     \seqsplit{updateSubscriptionOnServer(subscription);} \newline  \newline     isSubscribed = true; \newline  \newline   \}) \newline   \});} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\begin{tabularx}{5.377cm}{x{2.18988 cm} x{2.78712 cm} }
\SetRowColor{DarkBackground}
\mymulticolumn{2}{x{5.377cm}}{\bf\textcolor{white}{Get Application Server Keys}}  \tn
% Row 0
\SetRowColor{LightBackground}
Generate public/private keys & \seqsplit{https://web-push-codelab}.glitch.me/ \tn 
% Row Count 2 (+ 2)
% Row 1
\SetRowColor{white}
\mymulticolumn{2}{x{5.377cm}}{Insert them into your application} \tn 
% Row Count 3 (+ 1)
\hhline{>{\arrayrulecolor{DarkBackground}}--}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Handle Permission Denied}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{if (Notification.permission === 'denied') \{ \newline     pushButton.textContent = 'Push Messaging Blocked.'; \newline     pushButton.disabled = true; \newline     \seqsplit{updateSubscriptionOnServer(null);} \newline     return; \newline   \} \newline  \newline   if (isSubscribed) \{ \newline     pushButton.textContent = 'Disable Push Messaging'; \newline   \} else \{ \newline     pushButton.textContent = 'Enable Push Messaging'; \newline   \} \newline  \newline   pushButton.disabled = false;} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Handle a Push Event}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\seqsplit{self.addEventListener('push'}, function(event) \{ \newline   console.log('{[}Service Worker{]} Push Received.'); \newline   console.log(`{[}Service Worker{]} Push had this data: "\$\{event.data.text()\}"`); \newline  \newline   const title = 'Push Codelab'; \newline   const options = \{ \newline     body: 'Yay it works.', \newline     icon: 'images/icon.png', \newline     badge: 'images/badge.png' \newline   \}; \newline  \newline   \seqsplit{event.waitUntil(self.registration.showNotification(title}, options)); \newline \});} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Notification click}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\seqsplit{self.addEventListener('notificationclick'}, function(event) \{ \newline   console.log('{[}Service Worker{]} Notification click Received.'); \newline  \newline   \seqsplit{event.notification.close();} \newline  \newline   event.waitUntil( \newline     \seqsplit{clients.openWindow('https://developers.google.com/web/')} \newline   ); \newline \});} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Sending push messages}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Use \seqsplit{https://web-push-codelab.glitch.me/} to send a push message% Row Count 2 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Unsubscribe the user}}  \tn
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{\seqsplit{pushButton.addEventListener('click'}, function() \{ \newline   pushButton.disabled = true; \newline   if (isSubscribed) \{ \newline     unsubscribeUser(); \newline   \} else \{ \newline     subscribeUser(); \newline   \} \newline \}); \newline  \newline swRegistration.pushManager.getSubscription() \newline   \seqsplit{.then(function(subscription)} \{ \newline     if (subscription) \{ \newline       return \seqsplit{subscription.unsubscribe();} \newline     \} \newline   \}) \newline   .then(function() \{ \newline     \seqsplit{updateSubscriptionOnServer(null);} \newline  \newline     console.log('User is unsubscribed.'); \newline     isSubscribed = false; \newline  \newline     updateBtn(); \newline   \});} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


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

\end{document}