ExpandedBottomSheetDialogFragment.java

    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        val bottomSheetDialog = super.onCreateDialog(savedInstanceState) as BottomSheetDialog
        bottomSheetDialog.setOnShowListener {
            val dialog = it as BottomSheetDialog
            val bottomSheet = dialog.findViewById<View>(com.google.android.material.R.id.design_bottom_sheet)
            BottomSheetBehavior.from(bottomSheet).state = BottomSheetBehavior.STATE_EXPANDED
        }

        return bottomSheetDialog
    }