post pwa gp 🚀

Author: chicio

_drafts/2019-06-15-google-play-store-publish-pwa.md

@@ -16,15 +16,31 @@ authors: [fabrizio_duroni]
 ---
 
 A few months ago I [transformed my blog into a Progressive Web App](/2019/03/03/github-pages-progressive-web-app.html). As you may already know PWA let your websites behaves like a native mobile app but there's one thing that was still missing: the possibility to publish on the App Stores. Because even if a PWA as the advantage to be searchable as astandard website, this days user are used to search ofr apps on the App Stores for each platform. Well, starting from february 2019 this problem has been solved on the Android platform with the release of [Trusted Web Activities](https://developers.google.com/web/updates/2019/02/using-twa "trusted web activities").  
-In this post I will show you how I released the PWA of my blog to the Google Play Store using Trusted Web Activities (and also without writing a single line of Java code :smirk:).
-Let's start from the definition of what a Trusted Web Activities is, by quoting [the official Google developer website](https://developers.google.com/web/updates/2019/02/using-twa "trusted web activities").
+In this post I will show you how I released the PWA of my blog to the Google Play Store using Trusted Web Activities (and also without writing a single line of Java/Kotlin code :smirk:).
 
->There are a few things that make Trusted Web Activities different from other ways to integrate web content with your app:
+#### What is a Trusted Web Activity
+
+Let's start from the definition of Trusted Web Activitiy (TWA) taken from [the official Google developer website](https://developers.google.com/web/updates/2019/02/using-twa "trusted web activities").
+
+>There are a few things that make Trusted Web Activities (TWA) different from other ways to integrate web content with your app:
 >
 > * Content in a Trusted Web activity is trusted -- the app and the site it opens are expected to come from the same developer. (This is verified using Digital Asset Links.)
 > * Trusted Web activities come from the web: they're rendered by the user's browser, in exactly the same way as a user would see it in their browser except they are run fullscreen. Web content should be accessible and useful in the browser first.
 > * Browsers are also updated independent of Android and your app -- Chrome, for example, is available back to Android Jelly Bean. That saves on APK size and ensures you can use a modern web runtime. (Note that since Lollipop, WebView has also been updated independent of Android, but there are a significant number of pre-Lollipop Android users.)
 > * The host app doesn't have direct access to web content in a Trusted Web activity or any other kind of web state, like cookies and localStorage. Nevertheless, you can coordinate with the web content by passing data to and from the page in URLs (e.g. through query parameters, custom HTTP headers, and intent URIs.)
 > * Transitions between web and native content are between activities. Each activity (i.e. screen) of your app is either completely provided by the web, or by an Android activity
 
-....
+So as you can read above, a Trusted Web Activity let you integrate web content that you personally own into your app and let you execute it into the most modern web runtime (e.g. Chrome) available on the device of the user. Really cool!!! :heart_eyes:
+
+#### Implementation
+
+Let's start to see the real action: how I publish my blog PWA to the Google Play Store using TWA. First of all, I created a nw android project. This was a standard Android project with minimum API level 16. This let me cover the 99.6% of the Android user base. I choosed to create an empty project without any activity/fragment in it.
+
+{% include blog-lazy-image.html description="pwa app create project" src="/assets/images/posts/pwa-app-01-create-project.png" %}
+
+Then I added the TWA support as a dependecy of the app. The TWA implementation is contained inside the custom tabs client library published on jitpack (because unfortunately at the moment of this writing the custom tabs client library contained inside Jetpack doesn't have the TWA support). So I added jitpack as repository to the project level gradle file and the I added the custom tabs client library as dependecy inside the module gradle file. This dependecies points to the custom tabs client library published on github and exposed through Jitpack. I had also to specify a specific commit hash in order to be sure that the library version downloaded has dependecies contains the TWA support. 
+
+{% include blog-lazy-image.html description="pwa app jitpack" src="/assets/images/posts/pwa-app-02-jitpack-configuration.png" %}
+{% include blog-lazy-image.html description="pwa app custom tab library" src="/assets/images/posts/pwa-app-03-java8-and-custom-tab-dependecies.png" %}
+
+...