1 files changed, 84 insertions, 5 deletions

diff --git a/samples/browseable/RecyclerView/src/com.example.android.recyclerview/RecyclerViewFragment.java b/samples/browseable/RecyclerView/src/com.example.android.recyclerview/RecyclerViewFragment.java
index 4f4a5966a..019657ffb 100644
--- a/samples/browseable/RecyclerView/src/com.example.android.recyclerview/RecyclerViewFragment.java
+++ b/samples/browseable/RecyclerView/src/com.example.android.recyclerview/RecyclerViewFragment.java
@@ -18,21 +18,37 @@ package com.example.android.recyclerview;
 
 import android.os.Bundle;
 import android.support.v4.app.Fragment;
+import android.support.v7.widget.GridLayoutManager;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+import android.widget.RadioButton;
 
 /**
- * Demonstrates the use of RecyclerView with a LinearLayoutManager.
+ * Demonstrates the use of {@link RecyclerView} with a {@link LinearLayoutManager} and a
+ * {@link GridLayoutManager}.
  */
 public class RecyclerViewFragment extends Fragment {
 
     private static final String TAG = "RecyclerViewFragment";
+    private static final String KEY_LAYOUT_MANAGER = "layoutManager";
+    private static final int SPAN_COUNT = 2;
+    private static final int DATASET_COUNT = 60;
+
+    private enum LayoutManagerType {
+        GRID_LAYOUT_MANAGER,
+        LINEAR_LAYOUT_MANAGER
+    }
+
+    protected LayoutManagerType mCurrentLayoutManagerType;
+
+    protected RadioButton mLinearLayoutRadioButton;
+    protected RadioButton mGridLayoutRadioButton;
 
     protected RecyclerView mRecyclerView;
-    protected RecyclerView.Adapter mAdapter;
+    protected CustomAdapter mAdapter;
     protected RecyclerView.LayoutManager mLayoutManager;
     protected String[] mDataset;
 
@@ -58,23 +74,86 @@ public class RecyclerViewFragment extends Fragment {
         // to the way ListView would layout elements. The RecyclerView.LayoutManager defines how
         // elements are laid out.
         mLayoutManager = new LinearLayoutManager(getActivity());
-        mRecyclerView.setLayoutManager(mLayoutManager);
+
+        mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
+
+        if (savedInstanceState != null) {
+            // Restore saved layout manager type.
+            mCurrentLayoutManagerType = (LayoutManagerType) savedInstanceState
+                    .getSerializable(LAYOUT_MANAGER_KEY);
+        }
+        setRecyclerViewLayoutManager(mCurrentLayoutManagerType);
 
         mAdapter = new CustomAdapter(mDataset);
         // Set CustomAdapter as the adapter for RecyclerView.
         mRecyclerView.setAdapter(mAdapter);
         // END_INCLUDE(initializeRecyclerView)
 
+        mLinearLayoutRadioButton = (RadioButton) rootView.findViewById(R.id.linear_layout_rb);
+        mLinearLayoutRadioButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                setRecyclerViewLayoutManager(LayoutManagerType.LINEAR_LAYOUT_MANAGER);
+            }
+        });
+
+        mGridLayoutRadioButton = (RadioButton) rootView.findViewById(R.id.grid_layout_rb);
+        mGridLayoutRadioButton.setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                setRecyclerViewLayoutManager(LayoutManagerType.GRID_LAYOUT_MANAGER);
+            }
+        });
+
         return rootView;
     }
 
     /**
+     * Set RecyclerView's LayoutManager to the one given.
+     *
+     * @param layoutManagerType Type of layout manager to switch to.
+     */
+    public void setRecyclerViewLayoutManager(LayoutManagerType layoutManagerType) {
+        int scrollPosition = 0;
+
+        // If a layout manager has already been set, get current scroll position.
+        if (mRecyclerView.getLayoutManager() != null) {
+            scrollPosition = ((LinearLayoutManager) mRecyclerView.getLayoutManager())
+                    .findFirstCompletelyVisibleItemPosition();
+        }
+
+        switch (layoutManagerType) {
+            case GRID_LAYOUT_MANAGER:
+                mLayoutManager = new GridLayoutManager(getActivity(), SPAN_COUNT);
+                mCurrentLayoutManagerType = LayoutManagerType.GRID_LAYOUT_MANAGER;
+                break;
+            case LINEAR_LAYOUT_MANAGER:
+                mLayoutManager = new LinearLayoutManager(getActivity());
+                mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
+                break;
+            default:
+                mLayoutManager = new LinearLayoutManager(getActivity());
+                mCurrentLayoutManagerType = LayoutManagerType.LINEAR_LAYOUT_MANAGER;
+        }
+
+        mRecyclerView.setLayoutManager(mLayoutManager);
+        mRecyclerView.scrollToPosition(scrollPosition);
+    }
+
+    @Override
+    public void onSaveInstanceState(Bundle savedInstanceState) {
+        // Save currently selected layout manager.
+        savedInstanceState.putSerializable(LAYOUT_MANAGER_KEY, mCurrentLayoutManagerType);
+        super.onSaveInstanceState(savedInstanceState);
+    }
+
+    /**
      * Generates Strings for RecyclerView's adapter. This data would usually come
      * from a local content provider or remote server.
      */
     private void initDataset() {
-        mDataset = new String[60];
-        for (int i=0; i < 60; i++) {
+        mDataset = new String[DATASET_COUNT];
+        for (int i = 0; i < DATASET_COUNT; i++) {
             mDataset[i] = "This is element #" + i;
         }
     }