Merge "Fix overscroll distance calculation for stack-from-bottom ListViews"

2 files changed, 30 insertions, 7 deletions

diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index a1c3fa2..ce236c0 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -381,12 +381,12 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
     /**
      * Maximum distance to overscroll by
      */
-    private int mOverscrollMax;
+    int mOverscrollMax;
     
     /**
      * Content height divided by this is the overscroll limit.
      */
-    private static final int OVERSCROLL_LIMIT_DIVISOR = 3;
+    static final int OVERSCROLL_LIMIT_DIVISOR = 3;
 
     /**
      * Used to request a layout when we changed touch mode
@@ -2390,7 +2390,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
         awakenScrollBars();
     }
     
-    private int getOverscrollMax() {
+    int getOverscrollMax() {
         final int childCount = getChildCount();
         if (childCount > 0) {
             return Math.min(mOverscrollMax,
diff --git a/core/java/android/widget/ListView.java b/core/java/android/widget/ListView.java
index 0594844..27700fd 100644
--- a/core/java/android/widget/ListView.java
+++ b/core/java/android/widget/ListView.java
@@ -1250,10 +1250,19 @@ public class ListView extends AbsListView {
     int findMotionRow(int y) {
         int childCount = getChildCount();
         if (childCount > 0) {
-            for (int i = 0; i < childCount; i++) {
-                View v = getChildAt(i);
-                if (y <= v.getBottom()) {
-                    return mFirstPosition + i;
+            if (!mStackFromBottom) {
+                for (int i = 0; i < childCount; i++) {
+                    View v = getChildAt(i);
+                    if (y <= v.getBottom()) {
+                        return mFirstPosition + i;
+                    }
+                }
+            } else {
+                for (int i = childCount - 1; i >= 0; i--) {
+                    View v = getChildAt(i);
+                    if (y >= v.getTop()) {
+                        return mFirstPosition + i;
+                    }
                 }
             }
         }
@@ -3682,6 +3691,20 @@ public class ListView extends AbsListView {
             mCheckedIdStates.clear();
         }
     }
+    
+    @Override
+    int getOverscrollMax() {
+        if (mStackFromBottom) {
+            final int childCount = getChildCount();
+            if (childCount > 0) {
+                return Math.min(mOverscrollMax,
+                        (getHeight() - getChildAt(0).getTop()) / OVERSCROLL_LIMIT_DIVISOR);
+            } else {
+                return mOverscrollMax;
+            }
+        }
+        return super.getOverscrollMax();
+    }
 
     static class SavedState extends BaseSavedState {
         SparseBooleanArray checkState;