Set state of BottomSheetDialogFragment to expanded

Question

How do you set the state of a fragment extending BottomSheetDialogFragment to expanded using BottomSheetBehavior#setState(STATE_EXPANDED) using the

Answer 1

The easiest way I implemented is as below, Here we are finding android.support.design.R.id.design_bottom_sheet and setting bottom sheet state as EXPANDED.

Without this, my bottom sheet was always stuck in the COLLAPSED state if view height is more than 0.5 of screen height and I have to manually scroll to view full bottom sheet.

class BottomSheetDialogExpanded(context: Context) : BottomSheetDialog(context) {

    private lateinit var mBehavior: BottomSheetBehavior

    override fun setContentView(view: View) {
        super.setContentView(view)
        val bottomSheet = window.decorView.findViewById(android.support.design.R.id.design_bottom_sheet) as FrameLayout
        mBehavior = BottomSheetBehavior.from(bottomSheet)
        mBehavior.state = BottomSheetBehavior.STATE_EXPANDED
    }

    override fun onStart() {
        super.onStart()
        mBehavior.state = BottomSheetBehavior.STATE_EXPANDED
    }
}