QS Animations - first pass, still not spec

Bug: 27201532

Change-Id: I9a2a16f9d769db1f40ae733ad55a07ede4780698
diff --git a/packages/SystemUI/src/com/android/systemui/qs/PagedTileLayout.java b/packages/SystemUI/src/com/android/systemui/qs/PagedTileLayout.java
index 8e9857d..0915ee1 100644
--- a/packages/SystemUI/src/com/android/systemui/qs/PagedTileLayout.java
+++ b/packages/SystemUI/src/com/android/systemui/qs/PagedTileLayout.java
@@ -27,6 +27,7 @@
 
     private int mNumPages;
     private View mDecorGroup;
+    private PageListener mPageListener;
 
     public PagedTileLayout(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -36,10 +37,14 @@
             public void onPageSelected(int position) {
                 if (mPageIndicator == null) return;
                 mPageIndicator.setLocation(position);
+                if (mPageListener != null) {
+                    mPageListener.onPageChanged(position);
+                }
             }
 
             @Override
-            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
+            public void onPageScrolled(int position, float positionOffset,
+                    int positionOffsetPixels) {
                 if (mPageIndicator == null) return;
                 mPageIndicator.setLocation(position + positionOffset);
             }
@@ -80,6 +85,10 @@
         }
     }
 
+    public void setPageListener(PageListener listener) {
+        mPageListener = listener;
+    }
+
     private void postDistributeTiles() {
         removeCallbacks(mDistribute);
         post(mDistribute);
@@ -198,4 +207,8 @@
             return view == object;
         }
     };
+
+    public interface PageListener {
+        void onPageChanged(int page);
+    }
 }