Fix Sheet system bar visibility reads on legacy Android

androidApp/src/androidTest/kotlin/com/moriafly/salt/sample/ui/SheetInteractionTest.kt

@@ -98,8 +98,39 @@ import java.util.concurrent.atomic.AtomicReference
 class SheetInteractionTest {
     private val device get() = UiDevice.getInstance(InstrumentationRegistry.getInstrumentation())
 
+    @Test
+    fun sheetInheritsHiddenStatusBarOnLegacyAndroid() {
+        assumeTrue(Build.VERSION.SDK_INT < 30)
+        // On API 29 and below, inspect System UI itself so the assertion cannot repeat the
+        // compat insets misreading that this regression test is intended to catch.
+        val statusBar = By.res("com.android.systemui", "status_bar")
+        for (displayMode in listOf(SheetDisplayMode.Bottom, SheetDisplayMode.Floating)) {
+            val fixture = AndroidSheetFixture(displayMode = displayMode)
+            ActivityScenario.launch(MainActivity::class.java).use { scenario ->
+                scenario.onActivity { activity ->
+                    WindowCompat.getInsetsController(activity.window, activity.window.decorView)
+                        .hide(WindowInsetsCompat.Type.statusBars())
+                    activity.setContent { fixture.Content() }
+                }
+                shown(By.text("Open sheet"))
+                assertTrue(device.wait(Until.gone(statusBar), 5_000))
+                click(By.text("Open sheet"))
+                shown(By.text("Fixture sheet"))
+                assertTrue(device.wait(Until.gone(statusBar), 5_000))
+                click(By.text("Inside"))
+                shown(By.text("Inside: 1"))
+                assertTrue(device.wait(Until.gone(statusBar), 5_000))
+                click(By.text("Program close"))
+                assertTrue(device.wait(Until.gone(By.text("Fixture sheet")), 5_000))
+            }
+        }
+    }
+
     @Test
     fun sheetInheritsSystemBarsAndAllowsContentToManageThem() {
+        // On Android 10 (API 29) and earlier, dialog focus can clear the owner's hide flags.
+        // Opening inheritance is tested separately there; this full isolation check needs API 30+.
+        assumeTrue(Build.VERSION.SDK_INT >= 30)
         val statusBar = WindowInsetsCompat.Type.statusBars()
         val navigationBar = WindowInsetsCompat.Type.navigationBars()
         for (displayMode in listOf(SheetDisplayMode.Bottom, SheetDisplayMode.Floating)) {

ui2/src/androidMain/kotlin/com/moriafly/salt/ui/sheet/internal/SheetSystemBars.android.kt

@@ -21,16 +21,19 @@ package com.moriafly.salt.ui.sheet.internal
 
 import android.view.View
 import android.view.Window
-import androidx.core.view.ViewCompat
 import androidx.core.view.WindowCompat
 import androidx.core.view.WindowInsetsCompat
 
 /**
  * Initializes one Sheet dialog window with the owner's opening system bar visibility.
  *
  * Call [inheritOwnerVisibility] from the host's SideEffect after a successful composition.
- * Only the dialog's controller is changed; the owner keeps its own requests, so dismissal requires
- * no restoration. Further visibility changes belong to the developer controlling the dialog.
+ * Only the dialog's controller is changed. On Android 10 (API 29) and earlier, the platform can
+ * propagate cleared system UI flags to other windows during focus changes, removing the owner's
+ * hide requests. Restoring the opening snapshot could overwrite newer host requests, so no
+ * restoration is done on dismissal.
+ * On these versions, immersive hosts should reapply their current visibility when focus returns.
+ * Further visibility changes belong to the developer controlling the dialog.
  */
 internal class SheetSystemBars(
     window: Window,
@@ -72,7 +75,12 @@ internal class SheetSystemBars(
          * uses the platform's default visible bars.
          */
         fun readOwnerVisibility(ownerView: View): Visibility {
-            val insets = ViewCompat.getRootWindowInsets(ownerView)
+            // On Android 6–10 (API 23–29), root insets can retain layout space for hidden bars.
+            // ViewCompat.getRootWindowInsets() omits the window's system UI flags during conversion,
+            // so isVisible() can mistake that space for visible bars. Passing the View includes
+            // the window's hide flags in the calculation. API 30+ uses native visibility instead.
+            val insets = ownerView.rootWindowInsets
+                ?.let { WindowInsetsCompat.toWindowInsetsCompat(it, ownerView) }
             return Visibility(
                 statusBarVisible = insets?.isVisible(WindowInsetsCompat.Type.statusBars()) != false,
                 navigationBarVisible =