We know that how to fetch categories from shopify store there we get each category id that we ll used further to get products.

1. Main activity class to get product list :

public class ProductsListActivity extends AppCompatActivity implements ShopifyOperationInterface {

    private RecyclerView rvProducts;
    private RecyclerView.Adapter mAdapter;
    private ArrayList<Product> mArrayList;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_products_list);

        final String mCollectionId = getIntent().getStringExtra(AppConstant.sKeyCollectionId);
        rvProducts = (RecyclerView)findViewById(R.id.rvProducts);

        TextView tvTitle = (TextView) findViewById(R.id.tvTitle);
        rvProducts.setHasFixedSize(true);
        RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(ProductsListActivity.this);
        rvProducts.setLayoutManager(mLayoutManager);
        rvProducts.setItemAnimator(new DefaultItemAnimator());
        tvTitle.setText(getIntent().getStringExtra(AppConstant.sKeyCollectionName));

        mArrayList = ShopifyOperationsHandler.getProductList(Long.parseLong(mCollectionId), ProductsListActivity.this);

    }

    @Override
    public void success(String aType) {
        if (aType.equalsIgnoreCase(ProductsListActivity.class.getName())) {

            Log.e("list size:", mArrayList.size() + "");

            if (mArrayList != null && mArrayList.size() > 0) {
                rvProducts.setAdapter(mAdapter);
            }
        }
    }
}

2. Adapter class for product list :

public class AdapterProductsList extends RecyclerView.Adapter<AdapterProductsList.MyViewHolder> {

    private ArrayList<Product> mProductsDataArrayList;
    private Activity mActivity;


    public AdapterProductsList(ArrayList<Product> aProductsDataArrayList, Activity aActivity){
        mProductsDataArrayList = aProductsDataArrayList;
        mActivity = aActivity;
    }

    public static class MyViewHolder extends RecyclerView.ViewHolder {

        TextView tvWineName;
        ImageView imgWine;
        Button btnPrice;
        LinearLayout llAddCart;
        ProgressBar progressbarProducts;

        public MyViewHolder(View itemView) {
            super(itemView);
            this.tvWineName = (TextView) itemView.findViewById(R.id.tvWineName);
            this.imgWine = (ImageView) itemView.findViewById(R.id.imgWine);
            this.btnPrice = (Button) itemView.findViewById(R.id.btnPrice);
            this.llAddCart = (LinearLayout)itemView.findViewById(R.id.llAddCart);
            this.progressbarProducts = (ProgressBar)itemView.findViewById(R.id.progressbarProducts);

        }
    }


    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent,int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.item_products, parent, false);

        MyViewHolder myViewHolder = new MyViewHolder(view);

        return myViewHolder;
    }

    @Override
    public void onBindViewHolder(final MyViewHolder holder, final int listPosition) {

        TextView tvWineName = holder.tvWineName;
        ImageView imgWine = holder.imgWine;
        Button btnPrice = holder.btnPrice;
        LinearLayout llAddCart = holder.llAddCart;
        final ProgressBar progressBar = holder.progressbarProducts;

        tvWineName.setText(mProductsDataArrayList.get(listPosition).getTitle());

        btnPrice.setText("$" + mProductsDataArrayList.get(listPosition).getMinimumPrice());
    }

    @Override
    public int getItemCount() {
        return mProductsDataArrayList.size();
    }
}

3. Method to get products list :

public static ArrayList<Product> getProductList(Long aCollectionId, final Activity aActivity){

    final ArrayList<Product> mArrayList = new ArrayList<>();
    initializeProgress(aActivity);
    showProgress(aActivity);

    final ShopifyOperationInterface mShopifyOperationInterface = (ShopifyOperationInterface)aActivity;

    SampleApplication.getBuyClient().getProducts(1, aCollectionId, null, null, new Callback<List<Product>>() {
        @Override
        public void success(List<Product> products) {
            Log.e("products list size:", products.size() + "");
            if (products.size() > 0) {
                for (int i = 0; i < products.size(); i++) {
                    Log.e("products title:", products.get(i).getTitle() + "");
                    mArrayList.add(products.get(i));
                }
            }
            mShopifyOperationInterface.success(ProductsListActivity.class.getName());
        }

        @Override
        public void failure(BuyClientError error) {
            Log.e("products error:", error.getMessage());
            dismissProgress(aActivity);
        }
    });

    dismissProgress(aActivity);
    return mArrayList;

}

4. You can create your own item file like this :

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="5dp"
    android:orientation="vertical">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/list_item_color"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="@dimen/padding_ten"
            android:orientation="horizontal">

            <RelativeLayout
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:gravity="center">

                <ImageView
                    android:id="@+id/imgWine"
                    android:layout_width="@dimen/myceller_wine_size"
                    android:layout_height="@dimen/myceller_wine_size"
                    android:adjustViewBounds="true"
                    android:scaleType="centerInside"
                    android:layout_centerInParent="true"
                    android:src="@drawable/img_placeholder" />

                <ProgressBar
                    android:id="@+id/progressbarProducts"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerInParent="true"
                    android:background="@drawable/progress" />

            </RelativeLayout>

            <RelativeLayout
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="@dimen/padding_ten"
                android:layout_marginRight="@dimen/padding_ten"
                android:orientation="vertical">

                <TextView
                    android:id="@+id/tvWineName"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignParentLeft="true"
                    android:layout_alignParentTop="true"
                    android:layout_marginTop="@dimen/padding_ten"
                    android:layout_toLeftOf="@+id/llAddCart"
                    android:fadingEdge="horizontal"
                    android:marqueeRepeatLimit="marquee_forever"
                    android:paddingLeft="5dp"
                    android:paddingRight="5dp"
                    android:textColor="@color/dark_red"
                    android:textSize="@dimen/text_size_mid"
                    android:textStyle="bold" />

                <Button
                    android:id="@+id/btnPrice"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_below="@id/tvWineName"
                    android:layout_gravity="center"
                    android:layout_marginLeft="@dimen/padding_ten"
                    android:layout_marginTop="@dimen/padding_ten"
                    android:background="@drawable/red_btn_corner"
                    android:padding="5dp"
                    android:text=""
                    android:textColor="@color/white"
                    android:textSize="@dimen/text_size_large" />

                <LinearLayout
                    android:id="@+id/llAddCart"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignParentRight="true">

                    <ImageView
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:padding="@dimen/padding_ten"
                        android:src="@drawable/cart" />

                </LinearLayout>
            </RelativeLayout>

        </LinearLayout>
    </LinearLayout>

</android.support.v7.widget.CardView>

In our next blog you can check how can we add any product into cart.