zsmb.coEst. 2017

Announcing requireKTX

2021-06-17 • Márton Braun

So, I got tired of writing code like this.


And seeing others have to write code like this:

val channelType: String = inputData.getString(DATA_CHANNEL_TYPE)!!
val channelId: String = inputData.getString(DATA_CHANNEL_ID)!!
val messageId: String = inputData.getString(DATA_MESSAGE_ID)!!

So I created requireKTX.

What does it do?

It adds extensions so that the code above becomes this:


And this:

val channelType: String = inputData.requireString(DATA_CHANNEL_TYPE)
val channelId: String = inputData.requireString(DATA_CHANNEL_ID)
val messageId: String = inputData.requireString(DATA_MESSAGE_ID)

These extensions exist on various types (Bundle, Intent, WorkManager Data), and for various types of data you’d want to fetch (String, Int, and dozens more).

Instead of giving you nullable types or default values, they’ll throw meaningful exceptions (IllegalStateException or IllegalArgumentException) with nicely worded error messages describing why the value couldn’t be fetched.


You also get nicer getOrNull style methods for all these base types and all types you’d want to fetch, so that the possible nullability is explicit:

val userId: String? = requireArguments().getStringOrNull("user_id")

That’s all!

Check out the library on GitHub, give it a star ⭐, add it to your project, send feedback my way!

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