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 Android Support Design Library (v23.2.1)?

https://code.google.com/p/android/issues/detail?id=202396 says:

Bottom sheets are set to STATE_COLLAPSED at first. Call BottomSheetBehavior#setState(STATE_EXPANDED) if you want to expand it. Note that you cannot call the method before view layouts.

The suggested practice requires a view to be inflated first, but I'm not sure how I'll set the BottomSheetBehaviour onto a fragment (BottomSheetDialogFragment).

View bottomSheet = coordinatorLayout.findViewById(R.id.bottom_sheet);  
BottomSheetBehavior behavior = BottomSheetBehavior.from(bottomSheet);  

Answer 1

I wrote a subclass of BottomSheetDialogFragment to handle this:

public class NonCollapsableBottomSheetDialogFragment extends BottomSheetDialogFragment {

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    final BottomSheetDialog bottomSheetDialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);

    bottomSheetDialog.setOnShowListener(new DialogInterface.OnShowListener() {
        @Override
        public void onShow(DialogInterface dialog) {
            FrameLayout bottomSheet = bottomSheetDialog.findViewById(android.support.design.R.id.design_bottom_sheet);

            BottomSheetBehavior behavior = BottomSheetBehavior.from(bottomSheet);
            behavior.setSkipCollapsed(true);
            behavior.setState(BottomSheetBehavior.STATE_EXPANDED);
        }
    });
    return bottomSheetDialog;
}

}

So extend this class instead of BottomSheetDialogFragment to create your own bottom sheet.