LayoutInflater ignores XML attributes

Question

I have a problem with my LayoutInflater. First of all here is my item.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="100dp"
    android:layout_height="100dp"
    android:background="@drawable/button" >
 
</RelativeLayout>

(I deleted all unneccessary stuff for this question)

When I set my LayoutInflater in my RecyclerViewAdapter like this:

View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, null);

Everything works fine and it looks like I want it to be:

In many documentations and articles about LayouInflater they recommend using the LayoutInflater like this:

View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, parent, false);

But when I do that it ignores the attributes from the item.xml file :

There are a lot of articles out there who explain that the first method (the one who works for me) should be avoided. Here is one of those articles: https://web.archive.org/web/20190528213406/https://possiblemobile.com/2013/05/layout-inflation-as-intended/

Here is my full RecyclerView.Adapter class:

public class AdapterTest extends RecyclerView.Adapter<AdapterTest.TestViewHolder> {


    @Override
    public TestViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, null);
        return new TestViewHolder(v);
    }

    @Override
    public void onBindViewHolder(final TestViewHolder holder, int position) {


    }

    @Override
    public int getItemCount() {
        return 10;
    }

    public class TestViewHolder extends RecyclerView.ViewHolder {
 

        public TestViewHolder(View itemView) {
            super(itemView); 
        }
    }


}

How can I use the recommended way but still have the results I want?

Answer 1

I fixed it by adding these two lines inside the onCreateViewHolder:

RecyclerView.LayoutParams lp = new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
v.setLayoutParams(lp);

My onCreateViewHolder now looks like this:

@NonNull
@Override
public TestViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {

    View v = LayoutInflater.from(mContext).inflate(R.layout.item, parent, false);
    RecyclerView.LayoutParams lp = new RecyclerView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
    v.setLayoutParams(lp);
    return new TestViewHolder(v);
}

Here is the answer where I got that from: https://stackoverflow.com/a/30692398/7735807

I can't really explain why it works now because my RecyclerView was set on MatchParent width and hight from the beginning on. I'm just glad it works now