Bundle.getParcelableCompat と View.onRestoreInstanceState の組み合わせを試す

Test.kt

package jp.juggler.testparcelablecompat

import android.content.Context
import android.os.Build
import android.os.Bundle
import android.os.Parcelable
import android.util.Log
import android.view.View
import android.view.ViewGroup
import androidx.appcompat.app.AppCompatActivity
import jp.juggler.testparcelablecompat.BundleExt.getParcelableCompat

private const val TAG = "TestParcelableCompat"

class MainActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        Log.i(TAG, "MainActivity.onCreate savedInstanceState=$savedInstanceState")

        super.onCreate(savedInstanceState)

        val testView = TestView(this).apply {
            id = R.id.testView
            layoutParams = ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT,
            )
        }

        setContentView(testView)
    }
}

class TestView(context: Context) : View(context) {
    companion object {
        private const val STATE_SAVE_COUNT = "saveCount"
        private const val STATE_SUPER = "TestView.super"
    }

    private var saveCount = 0

    override fun onSaveInstanceState(): Parcelable =
        Bundle().apply {
            val superState = super.onSaveInstanceState()
            putParcelable(STATE_SUPER, superState)
            putInt(STATE_SAVE_COUNT, ++saveCount)

            Log.i(TAG, "TestView.onSaveInstanceState saveCount=$saveCount, superState=$superState")
        }

    override fun onRestoreInstanceState(state: Parcelable?) {
        Log.i(TAG, "TestView.onRestoreInstanceState state=$state")
        if (state is Bundle && state.containsKey(STATE_SUPER)) {
            val superState = state.getParcelableCompat<Parcelable>(STATE_SUPER)
            super.onRestoreInstanceState(superState)
            saveCount = state.getInt(STATE_SAVE_COUNT)
            Log.i(
                TAG,
                "TestView.onRestoreInstanceState saveCount=$saveCount, superState=$superState"
            )
        } else {
            super.onRestoreInstanceState(state)
        }
    }
}

object BundleExt {
    /**
     * API 33 で Bundle.getParcelable(1引数)が deprecatedになった
     * - 33 のソースを見ないとコレで動くのか分からん…
     */
    @Suppress("DEPRECATION")
    inline fun <reified T : Any> Bundle.getParcelableCompat(key: String) =
        if (Build.VERSION.SDK_INT >= 33) {
            getParcelable(key, T::class.java)
        } else {
            getParcelable(key) as? T
        }
}