Android Dialog Fragment RecyclerView wrap content but max height based on constraints?

Question

So I'm working on creating a dialog fragment to allow user to choose from some options. I have a pretty simple layout inside a constraint layout. TextView on top, recycler view, then two buttons at the bottom.

The problem is, I want the recyclerview to be wrap content, so that if there aren't a lot of options, the dialog will shrink down. However, if there are a lot of options, i'd like it to expand but then start scrolling so all views are visible on the screen.

I can't seem to get past the situation where either it constantly is large. Or if I just allow wrap content, the dialog will grow so large the bottom buttons are missing.

I'm assuming it has something to do with some particular constraint options, but I can't figure out the combination. Any ideas?

EDIT: I know an easy answer is to set a max height on the recycler view. I'm hoping to do that same thing but with constraints, so its not a fixed hard height.

EDIT2: It looks like the constraints will work nicely with wrap as default if the view model's height is fixed. I really can't deal with a fixed height view model though...

Thanks

Do any of the answers here work? (https://stackoverflow.com/questions/40850966/wrap-content-view-inside-a-constraintlayout-stretches-outside-the-screen) `app:layout_constrainedHeight="true"`. — Tyler V, Nov 04 '19 at 00:55
@TylerV Hey they work only if your ViewHolders have a fixed height. If those are wrap content (which i feel like is most view holders) then it doesn't size correctly. My guess is because it doesn't reliably know how to size if its content could be dynamic. This alone with dynamic height view holders causes it to grow to the constraints max at all times. — Kyle, Nov 04 '19 at 21:05

score 1 · Accepted Answer · answered Nov 04 '19 at 01:05

Create a customRecyclerView that override onMeasure method.

public class CustomRecyclerView extends RecyclerView{

    public CustomRecyclerView (Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public CustomRecyclerView (Context context) {
        super(context);
    }

    public CustomRecyclerView (Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
                MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, expandSpec);
    }

}

you can call the recyclerview like this

<com.example.yourpackage.CustomRecyclerView>

So no way to get around it with the existing RecyclerView huh? Seems like a gap between Recyclerviews and DialogFragments. Alright will go with this approach. Thanks. — Kyle, Nov 04 '19 at 20:47

Android Dialog Fragment RecyclerView wrap content but max height based on constraints?

1 Answers1