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

Similar to uregentx answer, in kotlin, you can declare your fragment class that extends from BottomSheetDialogFragment, and when the view is created you can set the dialog listener default state after the dialog is displayed.

STATE_COLLAPSED: The bottom sheet is visible but only showing its peek height.

STATE_EXPANDED: The bottom sheet is visible and its maximum height.

STATE_HALF_EXPANDED: The bottom sheet is visible but only showing its half height.

class FragmentCreateGroup : BottomSheetDialogFragment() {
      ...

    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,savedInstanceState: Bundle?): View? {
        // Set dialog initial state when shown
        dialog?.setOnShowListener {
            val bottomSheetDialog = it as BottomSheetDialog
            val sheetInternal: View = bottomSheetDialog.findViewById(com.google.android.material.R.id.design_bottom_sheet)!!
            BottomSheetBehavior.from(sheetInternal).state = BottomSheetBehavior.STATE_COLLAPSED
        }

        val view = inflater.inflate(R.layout.fragment_create_group, container, false)
        ...

        return view
    }
}

Remember using material design implementation in gradle.

implementation "com.google.android.material:material:$version"

Also take a look to material design reference Bottom Sheets