add recycleview buttons for category

app/src/main/java/com/example/yourcashiertest/activities/MainActivity.java

@@ -5,6 +5,7 @@ import androidx.appcompat.app.AppCompatActivity;
 import androidx.databinding.DataBindingUtil;
 import androidx.lifecycle.Observer;
 import androidx.lifecycle.ViewModelProvider;
+import androidx.recyclerview.widget.LinearLayoutManager;
 
 import android.Manifest;
 
@@ -98,6 +99,7 @@ public class MainActivity extends AppCompatActivity {
             popupMenu.show();
         });
 
+        binding.rvCategory.setLayoutManager(new LinearLayoutManager(MainActivity.this, LinearLayoutManager.HORIZONTAL, false));
         binding.rvProducts.setAdapter(adapter);
         viewModel = new ViewModelProvider(this).get(ProductViewModel.class);
         viewModel.getProducts().observe(this, adapter::setProducts);

app/src/main/res/layout/activity_main.xml

@@ -24,7 +24,7 @@
         <View
             android:id="@+id/rectangle_4"
             android:layout_width="match_parent"
-            android:layout_height="200dp"
+            android:layout_height="150dp"
             android:background="@drawable/rectangle_4"
             app:layout_constraintBottom_toTopOf="@id/rvProducts"
             app:layout_constraintEnd_toEndOf="parent"
@@ -113,13 +113,22 @@
             android:imeOptions="actionSearch"
             android:inputType="textCapWords"
             android:textSize="@dimen/text_default" />
-
+        <androidx.recyclerview.widget.RecyclerView
+            android:id="@+id/rvCategory"
+            android:layout_width="match_parent"
+            android:layout_height="0dp"
+            tools:listitem="@layout/category_item"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent"
+            app:layout_constraintTop_toBottomOf="@id/rectangle_4"
+            app:layout_constraintBottom_toTopOf="@id/rvProducts"
+            />
         <androidx.recyclerview.widget.RecyclerView
             android:id="@+id/rvProducts"
             android:layout_width="match_parent"
             android:layout_height="0dp"
             android:layout_marginVertical="15dp"
-            app:layout_constraintTop_toBottomOf="@id/rectangle_4"
+            app:layout_constraintTop_toBottomOf="@id/rvCategory"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintStart_toStartOf="parent"
             app:layout_constraintEnd_toEndOf="parent"

app/src/main/res/layout/category_item.xml

+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:tools="http://schemas.android.com/tools"
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <data>
+        <variable
+            name="category"
+            type="String" />
+    </data>
+
+    <androidx.constraintlayout.widget.ConstraintLayout
+        android:layout_height="wrap_content"
+        android:layout_width="wrap_content"
+        android:paddingVertical="10dp"
+        android:layout_marginHorizontal="3dp">
+
+        <com.google.android.material.card.MaterialCardView
+            android:id="@+id/cvCategory"
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:backgroundTint="@color/colorPrimaryDark"
+            android:clickable="true"
+            android:focusable="true"
+            android:checkable="true"
+            app:cardCornerRadius="10dp"
+            android:clipToPadding="true"
+            app:layout_constraintTop_toTopOf="parent"
+            app:layout_constraintBottom_toBottomOf="parent"
+            app:layout_constraintStart_toStartOf="parent"
+            app:layout_constraintEnd_toEndOf="parent">
+
+            <RelativeLayout
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:paddingHorizontal="20dp">
+                <TextView
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:text="Example"
+                    android:textStyle="bold"
+                    android:textSize="20sp"
+                    android:textColor="#fff"
+                    tools:text="elizabeth"
+                    android:layout_centerInParent="true"/>
+            </RelativeLayout>
+        </com.google.android.material.card.MaterialCardView>
+    </androidx.constraintlayout.widget.ConstraintLayout>
+</layout>