[Divider] Fixed lastItemDecorated not being applied to horizontal orientation. Also updated the demo to include both orientations.

Resolves #2802

PiperOrigin-RevId: 461247080
(cherry picked from commit 6eeb95f)

Author: leticiarossi

catalog/java/io/material/catalog/divider/DividerItemDecorationDemoFragment.java

@@ -33,10 +33,6 @@
 /** Demo of the MaterialDividerItemDecoration. */
 public class DividerItemDecorationDemoFragment extends DemoFragment {
 
-  private RecyclerView recyclerView;
-  private DividerAdapter adapter;
-  private RecyclerView.LayoutManager layoutManager;
-
   @Nullable
   @Override
   public View onCreateDemoView(
@@ -47,24 +43,34 @@ public View onCreateDemoView(
         layoutInflater.inflate(
             R.layout.cat_divider_recyclerview_fragment, viewGroup, /* attachToRoot */ false);
 
-    recyclerView = view.findViewById(R.id.divider_recyclerview);
-    layoutManager = new LinearLayoutManager(getContext(), LinearLayoutManager.VERTICAL, false);
+    RecyclerView recyclerViewHorizontal = view.findViewById(R.id.divider_recyclerview_horizontal);
+    RecyclerView recyclerViewVertical = view.findViewById(R.id.divider_recyclerview_vertical);
+
+    setUpDividers(recyclerViewHorizontal, LinearLayoutManager.HORIZONTAL);
+    setUpDividers(recyclerViewVertical, LinearLayoutManager.VERTICAL);
+
+    return view;
+  }
+
+  private void setUpDividers(@NonNull RecyclerView recyclerView, int orientation) {
+    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext(),
+        orientation, false);
     recyclerView.setLayoutManager(layoutManager);
 
     MaterialDividerItemDecoration divider =
-        new MaterialDividerItemDecoration(getContext(), LinearLayoutManager.VERTICAL);
+        new MaterialDividerItemDecoration(getContext(), orientation);
     recyclerView.addItemDecoration(divider);
 
-    adapter = new DividerAdapter();
+    DividerAdapter adapter = new DividerAdapter();
     recyclerView.setAdapter(adapter);
-
-    return view;
   }
 
   /** A RecyclerView adapter. */
   private static final class DividerAdapter
       extends RecyclerView.Adapter<DividerAdapter.MyViewHolder> {
 
+    private static final int ITEM_COUNT = 20;
+
     /** Provide a reference to the views for each data item. */
     private static class MyViewHolder extends RecyclerView.ViewHolder {
 
@@ -95,7 +101,7 @@ public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
 
     @Override
     public int getItemCount() {
-      return 30;
+      return ITEM_COUNT;
     }
   }
 }

catalog/java/io/material/catalog/divider/res/layout/cat_divider_recyclerview_fragment.xml

@@ -15,9 +15,40 @@
   limitations under the License.
   -->
 
-<androidx.recyclerview.widget.RecyclerView
-    xmlns:android="http://schemas.android.com/apk/res/android"
-    android:id="@+id/divider_recyclerview"
-    android:layout_height="wrap_content"
+<ScrollView
+  xmlns:android="http://schemas.android.com/apk/res/android"
+  android:layout_width="match_parent"
+  android:layout_height="match_parent">
+  <LinearLayout
     android:layout_width="match_parent"
-    android:layout_margin="16dp"/>
+    android:layout_height="wrap_content"
+    android:layout_margin="16dp"
+    android:orientation="vertical">
+
+    <!-- Horizontal orientation dividers. -->
+    <TextView
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginBottom="16dp"
+      android:textAppearance="?attr/textAppearanceTitleLarge"
+      android:text="@string/cat_divider_item_decoration_horizontal"/>
+    <androidx.recyclerview.widget.RecyclerView
+      android:id="@+id/divider_recyclerview_horizontal"
+      android:layout_marginBottom="16dp"
+      android:layout_height="wrap_content"
+      android:layout_width="match_parent"/>
+
+    <!-- Vertical orientation dividers. -->
+    <TextView
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"
+      android:layout_marginBottom="16dp"
+      android:textAppearance="?attr/textAppearanceTitleLarge"
+      android:text="@string/cat_divider_item_decoration_vertical"/>
+    <androidx.recyclerview.widget.RecyclerView
+        android:id="@+id/divider_recyclerview_vertical"
+        android:layout_height="wrap_content"
+        android:layout_width="match_parent"
+        android:layout_marginBottom="48dp"/>
+  </LinearLayout>
+</ScrollView>

catalog/java/io/material/catalog/divider/res/layout/cat_divider_recyclerview_item.xml

@@ -17,8 +17,7 @@
 
 <TextView
     xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="match_parent"
+    android:layout_width="wrap_content"
     android:layout_height="wrap_content"
-    android:layout_marginTop="8dp"
-    android:layout_marginBottom="8dp"
+    android:layout_margin="8dp"
     android:textAppearance="?attr/textAppearanceSubtitle1"/>

catalog/java/io/material/catalog/divider/res/values/strings.xml

@@ -66,4 +66,12 @@
       description="Label of the item in the MaterialDividerItemDecoration demo [CHAR_LIMIT=20]">
     Item %1$d
   </string>
+  <string name="cat_divider_item_decoration_horizontal"
+    description="Subtitle label for dividers with horizontal orientation [CHAR_LIMIT=NONE]">
+    Layout manager with horizontal orientation
+  </string>
+  <string name="cat_divider_item_decoration_vertical"
+    description="Subtitle label for dividers with vertical orientation [CHAR_LIMIT=NONE]">
+    Layout manager with vertical orientation
+  </string>
 </resources>

lib/java/com/google/android/material/divider/MaterialDividerItemDecoration.java

@@ -352,10 +352,11 @@ private void drawForHorizontalOrientation(@NonNull Canvas canvas, @NonNull Recyc
     bottom -= insetEnd;
 
     int childCount = parent.getChildCount();
-    for (int i = 0; i < childCount; i++) {
+    int dividerCount = lastItemDecorated ? childCount : childCount - 1;
+    for (int i = 0; i < dividerCount; i++) {
       View child = parent.getChildAt(i);
-      parent.getLayoutManager().getDecoratedBoundsWithMargins(child, tempRect);
-      // Take into consideration any translationY added to the view.
+      parent.getDecoratedBoundsWithMargins(child, tempRect);
+      // Take into consideration any translationX added to the view.
       int right = tempRect.right + Math.round(child.getTranslationX());
       int left = right - dividerDrawable.getIntrinsicWidth() - thickness;
       dividerDrawable.setBounds(left, top, right, bottom);