commit 36147983cb821ede03f569a562133a08cac9bcdf
author Annie Chin <afchin@google.com> Thu Dec 01 15:07:34 2016 -0800
committer Annie Chin <afchin@google.com> Mon Dec 05 15:26:29 2016 -0800
tree 42a6ee6c24925d1cb059798bc6f63ec4d17283f9
parent f1c92ca966b0ad3cd52c50160117e33706f2a361

Implement grouped headers.

Fixes: 32943152
Fixes: 33203390
Fixes: 33105914

-Add divider
-Adjust padding to better match spec
-Make HistoryFormula/Result padding match DisplayFormula/Result padding

Change-Id: I5e5a7e61079b6d1367bf61f4c88dd79555f4bcb7

src/com/android/calculator2/HistoryFragment.java

diff --git a/src/com/android/calculator2/HistoryFragment.java b/src/com/android/calculator2/HistoryFragment.java
index 22adcd3..f65f1e9 100644
--- a/src/com/android/calculator2/HistoryFragment.java
+++ b/src/com/android/calculator2/HistoryFragment.java
@@ -20,7 +20,9 @@
 import android.animation.ObjectAnimator;
 import android.app.Fragment;
 import android.app.FragmentTransaction;
+import android.graphics.Color;
 import android.os.Bundle;
+import android.support.v4.content.ContextCompat;
 import android.support.v7.widget.RecyclerView;
 import android.view.LayoutInflater;
 import android.view.MenuItem;
@@ -96,6 +98,7 @@
         mRecyclerView = (RecyclerView) view.findViewById(R.id.history_recycler_view);
 
         // The size of the RecyclerView is not affected by the adapter's contents.
+        mRecyclerView.setHasFixedSize(true);
         mRecyclerView.setAdapter(mAdapter);
 
         final Toolbar toolbar = (Toolbar) view.findViewById(R.id.history_toolbar);
@@ -153,7 +156,11 @@
             for (long i = 0; i < maxIndex; ++i) {
                 newDataSet.add(null);
             }
-            if (newDataSet.isEmpty()) {
+            final boolean isEmpty = newDataSet.isEmpty();
+            mRecyclerView.setBackgroundColor(isEmpty
+                    ? ContextCompat.getColor(activity, R.color.empty_history_color)
+                    : Color.TRANSPARENT);
+            if (isEmpty) {
                 newDataSet.add(new HistoryItem());
             }
             mDataSet = newDataSet;