In <https://github.com/terrakok/Compose-Multiplatform-Wizard> why is it creating the `AndroidApp` cl...

# multiplatform

[aj]

In https://github.com/terrakok/Compose-Multiplatform-Wizard why is it creating the AndroidApp class is implemented as a singleton!? 🤔

[xoangon]

The AndroidApp is not created as a singleton, as it is not even created manually. It’s only holding an static reference to the app instance created on the app startup

[aj]

Yes

[aj]

Exactly

[aj]

Not a singleton per se yeah, wrong description

[aj]

class AndroidApp : Application() {
    companion object {
        lateinit var INSTANCE: AndroidApp
    }

    override fun onCreate() {
        super.onCreate()
        INSTANCE = this
    }
}

[aj]

Why such behavior?

[Casey Brooks]

The Application class is always a singleton, because that’s how the Android framework creates and handles it. The generator is not creating the singleton, it’s just assigning the instance to a variable to make it easy to access throughout the rest of the app. This is a very common pattern among Android apps (though it’s arguable whether or not it is a good or necessary pattern in pure compose apps)

The alternative would be something like context.applicationContext as AndroidApp, littering your app with unchecked casts

[xoangon]

I was pretty much going to say the same as @Casey Brooks. The Application instance won’t be garbage collected as it’s always used. So there’s no penalty on having it as an static reference, and it’s pretty handy for some use cases

[aj]

Thanks!

[Arkadii Ivanov]

I believe it's still not recommended to store Application context into a global variable.
1. It may break features like Instant Run/Live Edit
2. If the process is killed and a ContentProvider is called, the application may be still null.

[Arkadii Ivanov]

There should also be a lint warning about it. At least it was in Java, as far as I remember.

[xoangon]

I was unaware of what you’re saying here @Arkadii Ivanov. Thanks for the info!

[Eugen Martynov]

I think it is “dirty” example for simplest dependency container