Behavior change to ItemSection and NestedSection (#90)

OnItemClickListener is added to ItemSection and onSectionExpansionToggled behavior is fixed. Test cases for both changes are updated.

Author: DevAhamed

multi-view-adapter/src/main/java/mva2/adapter/ItemSection.java

@@ -23,6 +23,7 @@
 import mva2.adapter.internal.ItemMetaData;
 import mva2.adapter.internal.RecyclerItem;
 import mva2.adapter.util.Mode;
+import mva2.adapter.util.OnItemClickListener;
 
 /**
  * Section which displays a single item inside the RecyclerView. For example, ItemSection can be
@@ -34,6 +35,7 @@
 
   @Nullable private M item;
   @Nullable private ItemMetaData itemMetaData;
+  @Nullable private OnItemClickListener<M> onItemClickListener;
 
   /**
    * No-arg constructor for ItemSection. This sets the {@link ItemSection#item} as null. This
@@ -94,6 +96,16 @@ public void setItem(@NonNull M item) {
     }
   }
 
+  /**
+   * Set the listener to get callback when an item is clicked inside the section. To invoke this
+   * listener, you need to call {@link ItemViewHolder#onItemClick()}
+   *
+   * @param onItemClickListener Listener to be set
+   */
+  public void setOnItemClickListener(@Nullable OnItemClickListener<M> onItemClickListener) {
+    this.onItemClickListener = onItemClickListener;
+  }
+
   //////////////////////////////////////////////////////////////////////////////////////
   /// ------------------------------------------------------------------------------ ///
   /// ---------------------  CAUTION : INTERNAL METHODS AHEAD  --------------------- ///
@@ -102,6 +114,12 @@ public void setItem(@NonNull M item) {
   /// ------------------------------------------------------------------------------ ///
   //////////////////////////////////////////////////////////////////////////////////////
 
+  @Override void onItemClicked(int position) {
+    if (null != onItemClickListener && position == 0 && getCount() > 0) {
+      onItemClickListener.onItemClicked(position, item);
+    }
+  }
+
   @Override Object getItem(int position) {
     return item;
   }

multi-view-adapter/src/main/java/mva2/adapter/ItemViewHolder.java

@@ -104,7 +104,7 @@ public boolean isSectionExpanded() {
    * If you set the {@link OnItemClickListener} for your ListSection, call this method to get
    * notified.
    */
-  public void onClick() {
+  public void onItemClick() {
     adapter.onItemClicked(getAdapterPosition());
   }
 

multi-view-adapter/src/main/java/mva2/adapter/ListSection.java

@@ -338,8 +338,7 @@ public void setDiffUtil(MvaDiffUtil<M> diffUtil) {
 
   /**
    * Set the listener to get callback when an item is clicked inside the section. To invoke this
-   * listener,
-   * you need to call {@link ItemViewHolder#onClick()}
+   * listener, you need to call {@link ItemViewHolder#onItemClick()}
    *
    * @param itemClickListener Listener to be set
    */

multi-view-adapter/src/main/java/mva2/adapter/NestedSection.java

@@ -258,9 +258,7 @@ itemPosition < getCount() && itemPosition >= 0 ? getModeToHonor(expansionMode,
 
   @Override int onSectionExpansionToggled(int itemPosition, @NonNull Mode sectionExpansionMode) {
     Mode mode = getModeToHonor(sectionExpansionMode, this.sectionExpansionMode);
-    if (itemPosition < getCount() && itemPosition >= 0) {
-      onChildSectionExpansionToggled(itemPosition, mode);
-    }
+    onChildSectionExpansionToggled(itemPosition, mode);
     return itemPosition - getCount();
   }
 

multi-view-adapter/src/main/java/mva2/adapter/Section.java

@@ -237,6 +237,7 @@ public void setSpanCount(int spanCount) {
   public void showSection() {
     if (isSectionHidden) {
       isSectionHidden = false;
+      onDataSetChanged();
       onInserted(0, getCount());
     }
   }

multi-view-adapter/src/main/java/mva2/adapter/util/OnItemClickListener.java

@@ -23,12 +23,12 @@
 /**
  * This interface lets you listen to the click event of the items inside the ListSection or
  * ItemSection. You can attach this listener to the section and listen for click events. To pass
- * down the click events to this interface call {@link ItemViewHolder#onClick()} method.
+ * down the click events to this interface call {@link ItemViewHolder#onItemClick()} method.
  *
  * @param <M> Model used in the {@link ListSection} or {@link ItemSection} where this listener is
  *            attached.
  *
- * @see ItemViewHolder#onClick()
+ * @see ItemViewHolder#onItemClick()
  */
 public interface OnItemClickListener<M> {
 

multi-view-adapter/src/test/java/mva2/adapter/CoreExpansionTest.java

@@ -124,7 +124,7 @@
     assertTrue(adapter.isItemExpanded(1));
   }
 
-  @Test public void selectionModeTest_SectionSingle() {
+  @Test public void expansionModeTest_SectionSingle() {
     adapter.setExpansionMode(Mode.MULTIPLE);
     listSection1.setExpansionMode(Mode.SINGLE);
     listSection2.setExpansionMode(Mode.SINGLE);
@@ -141,7 +141,7 @@
     assertTrue(adapter.isItemExpanded(1));
   }
 
-  @Test public void selectionModeTest_SectionSingle_1() {
+  @Test public void expansionModeTest_SectionSingle_1() {
     adapter.setExpansionMode(Mode.MULTIPLE);
     listSection1.setExpansionMode(Mode.SINGLE);
     listSection2.setExpansionMode(Mode.SINGLE);

multi-view-adapter/src/test/java/mva2/adapter/MultiViewAdapterTest.java

@@ -17,15 +17,21 @@
 package mva2.adapter;
 
 import mva2.adapter.testconfig.CommentBinder;
+import mva2.adapter.testconfig.Header;
 import mva2.adapter.testconfig.HeaderBinder;
 import mva2.adapter.testconfig.TestItem;
 import mva2.adapter.testconfig.TestItemBinder;
 import mva2.adapter.util.Mode;
+import mva2.adapter.util.OnItemClickListener;
 import org.junit.Test;
+import org.mockito.Mockito;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -257,4 +263,11 @@ public void getItemViewTypeTest_unRegisterBinders() {
     adapter.addSection(new ListSection<>());
     assertEquals(adapter.getItemCount(), 0);
   }
+
+  @Test public void onItemClicked_test() {
+    OnItemClickListener<Header> listener = Mockito.mock(OnItemClickListener.class);
+    itemSection1.setOnItemClickListener(listener);
+    adapter.onItemClicked(0);
+    verify(listener, times(1)).onItemClicked(anyInt(), any(Header.class));
+  }
 }

multi-view-adapter/src/test/java/mva2/adapter/SectionExpansionTest.java

@@ -0,0 +1,59 @@
+package mva2.adapter;
+
+import mva2.adapter.util.Mode;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.junit.MockitoJUnitRunner;
+
+import static junit.framework.Assert.assertEquals;
+
+@RunWith(MockitoJUnitRunner.class) public class SectionExpansionTest extends BaseTest {
+
+  @Test public void sectionExpansionModeTest_Single() {
+    adapter.removeAllSections();
+    adapter.addSection(itemSection1);
+    adapter.addSection(listSection1);
+    adapter.addSection(headerSection1);
+    adapter.addSection(nestedSection1);
+
+    adapter.setSectionExpansionMode(Mode.SINGLE);
+
+    adapter.collapseAllSections();
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 40);
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 31);
+
+    adapter.onSectionExpansionToggled(30);
+    assertEquals(adapter.getItemCount(), 40);
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 40);
+  }
+
+  @Test public void sectionExpansionModeTest_Multiple() {
+    adapter.removeAllSections();
+    adapter.addSection(itemSection1);
+    adapter.addSection(listSection1);
+    adapter.addSection(headerSection1);
+    adapter.addSection(nestedSection1);
+
+    adapter.setSectionExpansionMode(Mode.MULTIPLE);
+
+    adapter.collapseAllSections();
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 40);
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 31);
+
+    adapter.onSectionExpansionToggled(30);
+    assertEquals(adapter.getItemCount(), 40);
+
+    adapter.onSectionExpansionToggled(19);
+    assertEquals(adapter.getItemCount(), 49);
+  }
+}