At the 2017 Google I/O conference five years ago, GoogleAnnounce: Officially supports Kotlin as a First-Class (first-class citizen) language for Android development.Since then, Kotlin developers JetBrains and Google have been working closely around Kotlin and co-founded the Kotlin Foundation.

As highlighted in the original I/O announcement, Kotlin is an interoperable, mature, production-ready, and open-source programming language. There’s also excellent IDE support, as JetBrains developed the language and its companion tools at the same time.

Now, five years have passed since the official announcement. Let’s review the important development events of Kotlin on Android.

At the Google I/O 2017 developer conference, it was officially announced that it would support Kotlin as an Android developer First-Class language. As soon as the news came out, it immediately aroused extensive attention and heated discussions among relevant practitioners at home and abroad.

At Google I/O 2019, Google announced that Kotlin has become the language of choice for Android app developers.then“In the past two years, Kotlin’s popularity has been increasing, and over 50% of professional Android developers now use Kotlin to develop their apps,” said Chet Haase, Google’s chief Android evangelist.He also said that we are takingThe next big step is Kotlin-first, Android development will increasingly be dominated by Kotlin. “Many of the new Jetpack APIs and features will be available in Kotlin first,” Chet said. “If you’re starting a new project, you should write in Kotlin, which reduces the amount of code a lot, while also reducing the burden of testing and maintenance.” “

In this year’s survey, Kotlin was a huge hit, growing from 2.4% usage last year to 5.5%.From the initial support for Kotlin to “Kotlin-first”, Google has been supporting it in multiple directions, and has successively launched Kotlin Free Online Courseand courses on building Android applications with Kotlin; at the same time, the related ecology is continuously improved, such as open source gRPC-Kotlin/JVMmaking it easier for developers to use gRPC in Kotlin projects.

JetBrains announced a newJetpack Compose for Web“The new tool, the official introduction said that this project is based on Google’s modern UI toolkit Jetpack Compose,Support for writing responsive web UI with Kotlin.

Jetpack Compose is the new Android toolkit for building native interfaces. It simplifies and speeds up interface development on Android. Quickly bring your apps to life with less code, powerful tools, and an intuitive Kotlin API. The UI code and preview are shown below:

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