IssueTracker

Jetpack Compose version: 1.5.0
Jetpack Compose component used: material3: 1.1.1
Android Studio Build: Android Studio Giraffe | 2022.3.1
Kotlin version: 1.9.0

In our scenario, we open a ModalBottomSheet in order to edit or submit payment card details. We need to prevent the contents of the sheet from being screenshot, recorded, etc. For that purpose we typically set WindowManager.LayoutParams.FLAG_SECURE flag on a parent's activity's window. This work fine for regular composables, but not for bottomSheets.

Steps to Reproduce or Code Sample to Reproduce:

1. Add/Open a ModalBottomSheet composable and attempt to set WindowManager.LayoutParams.FLAG_SECURE flag on a window e.g.:

  val context = LocalContext.current
  val window = context.requireActivity().window
  val originalValue = rememberSaveable { window.isScreenshotDisabled() }

  DisposableEffect(Unit) {
    window.disableScreenshots(true)
    onDispose {
      window.disableScreenshots(originalValue)
    }
  }

2. Record the screen or take a screenshot.
3. Contents of BottomSheet are visible, while the typical composables are blacked out (Pixel). In case of Samsung devices and similar, any secured part of the screen prevents screenshots from happening, so screenshots are affecting only Pixel phones?!
4. Screen recording is able to capture the contents of BottomSheet on any device with or without the flag.

I suspect that the responsible code resides in ModalBottomSheetWindow class and it's params that are not considering the parent activity's flags and/or does not allow to specify the flags. Also, type = WindowManager.LayoutParams.TYPE_APPLICATION_PANEL might play some role, as the panel is AFAIK placed in a different window above the application.

private class ModalBottomSheetWindow(
    // ...
) :
    AbstractComposeView(composeView.context),
    ViewTreeObserver.OnGlobalLayoutListener,
    ViewRootForInspector {
    // ...

    private val windowManager =
        composeView.context.getSystemService(Context.WINDOW_SERVICE) as WindowManager

    private val params: WindowManager.LayoutParams =
        WindowManager.LayoutParams().apply {
            // Position bottom sheet from the bottom of the screen
            gravity = Gravity.BOTTOM or Gravity.START
            // Application panel window
            type = WindowManager.LayoutParams.TYPE_APPLICATION_PANEL
            // Fill up the entire app view
            width = displayWidth
            height = WindowManager.LayoutParams.MATCH_PARENT

            // Format of screen pixels
            format = PixelFormat.TRANSLUCENT
            // Title used as fallback for a11y services
            // TODO: Provide bottom sheet window resource
            title = composeView.context.resources.getString(
                androidx.compose.ui.R.string.default_popup_window_title
            )
            // Get the Window token from the parent view
            token = composeView.applicationWindowToken

            // Flags specific to modal bottom sheet.
            flags = flags and (
                WindowManager.LayoutParams.FLAG_IGNORE_CHEEK_PRESSES or
                WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM
            ).inv()

            flags = flags or WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS
        }
// ...
}

I was able to prevent screenshots/recording from happening by adding another view to the WindowManager in a similar manner to what ModalBottomSheetWindow is doing in it's show() function, only with the proper flag being set and making a sub_panel, to be placed above the bottomSheet.