隐藏键盘后，Android BottomSheet消失了

Question

Screen record

TestAvtivity.kt

class TestActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_test)

        val behavior = BottomSheetBehavior.from(bottomSheet)
        bottomSheet.post {
            behavior.state = BottomSheetBehavior.STATE_EXPANDED
        }

        startBtn.setOnClickListener {
            val intent = Intent(this, SearchTestActivity::class.java)
            startActivity(intent)
        }
    }
}

activity_test.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="com.google.android.material.appbar.AppBarLayout$ScrollingViewBehavior">

        <androidx.appcompat.widget.AppCompatButton
            android:id="@+id/startBtn"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="OPEN SAERCH" />
    </FrameLayout>

    <androidx.core.widget.NestedScrollView
        android:id="@+id/bottomSheet"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:layout_gravity="bottom"
        android:background="@color/light_green_900"
        app:layout_behavior="@string/bottom_sheet_behavior">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            style="@style/TextAppearance.AppCompat.Title"
            android:layout_gravity="center"
            android:text="BottomSheet"/>
    </androidx.core.widget.NestedScrollView>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

SearchTestActivity.kt

class SearchTestActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_search_test)

        finishBtn.setOnClickListener { finish() }
    }
}

当我用键盘完成一项活动（请参阅屏幕记录）时，底片消失了，并且有时底片在展开后立即消失了，我现在无法再次出现，如何解决它，谢谢。

编辑1 我通过在STATE_EXPANDED中设置onResume()并在STATE_HIDDEN中设置onPaues()来解决它

class TestActivity : AppCompatActivity() {

    private lateinit var behavior: BottomSheetBehavior<*>

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_test)

        behavior = BottomSheetBehavior.from(bottomSheet)
        behavior.isHideable = true
        behavior.state = BottomSheetBehavior.STATE_HIDDEN

        startBtn.setOnClickListener {
            val intent = Intent(this, SearchTestActivity::class.java)
            startActivity(intent)
        }
    }

    override fun onResume() {
        super.onResume()
        if (behavior.state == BottomSheetBehavior.STATE_HIDDEN) {
            bottomSheet.post {
                behavior.state = BottomSheetBehavior.STATE_EXPANDED
            }
        }
    }

    override fun onPause() {
        super.onPause()
        behavior.state = BottomSheetBehavior.STATE_HIDDEN
    }
}