BottomSheetDialogFragmentを全画面表示するExtension。onViewCreatedでcallする。

BottomSheetDialogFragmentExtensions.kt

/**
 * BottomSheetDialogを全画面表示する
 */
fun BottomSheetDialogFragment.fullScreen() {
    dialog?.setOnShowListener { dialog ->
        val d = dialog as BottomSheetDialog
        val bottomSheet =
            d.findViewById<FrameLayout>(R.id.design_bottom_sheet) ?: return@setOnShowListener
        bottomSheet.layoutParams.height = FrameLayout.LayoutParams.MATCH_PARENT
        val screenHeight = Resources.getSystem().displayMetrics.heightPixels
        BottomSheetBehavior.from(bottomSheet).peekHeight = screenHeight
    }
}