diff --git a/src/com/android/launcher3/allapps/AllAppsTransitionController.java b/src/com/android/launcher3/allapps/AllAppsTransitionController.java
index b436fa2..3b370bd 100644
--- a/src/com/android/launcher3/allapps/AllAppsTransitionController.java
+++ b/src/com/android/launcher3/allapps/AllAppsTransitionController.java
@@ -9,7 +9,6 @@
 import android.graphics.Color;
 import android.support.v4.graphics.ColorUtils;
 import android.support.v4.view.animation.FastOutSlowInInterpolator;
-import android.util.Log;
 import android.view.MotionEvent;
 import android.view.View;
 import android.view.animation.AccelerateInterpolator;
@@ -47,11 +46,10 @@
     private final Interpolator mAccelInterpolator = new AccelerateInterpolator(2f);
     private final Interpolator mDecelInterpolator = new DecelerateInterpolator(3f);
     private final Interpolator mFastOutSlowInInterpolator = new FastOutSlowInInterpolator();
-    private final ScrollInterpolator mScrollInterpolator = new ScrollInterpolator();
+    private final VerticalPullDetector.ScrollInterpolator mScrollInterpolator
+            = new VerticalPullDetector.ScrollInterpolator();
 
-    private static final float ANIMATION_DURATION = 1200;
     private static final float PARALLAX_COEFFICIENT = .125f;
-    private static final float FAST_FLING_PX_MS = 10;
     private static final int SINGLE_FRAME_MS = 16;
 
     private AllAppsContainerView mAppsView;
@@ -315,13 +313,7 @@
     }
 
     private void calculateDuration(float velocity, float disp) {
-        // TODO: make these values constants after tuning.
-        float velocityDivisor = Math.max(2f, Math.abs(0.5f * velocity));
-        float travelDistance = Math.max(0.2f, disp / mShiftRange);
-        mAnimationDuration = (long) Math.max(100, ANIMATION_DURATION / velocityDivisor * travelDistance);
-        if (DBG) {
-            Log.d(TAG, String.format("calculateDuration=%d, v=%f, d=%f", mAnimationDuration, velocity, disp));
-        }
+        mAnimationDuration = mDetector.calculateDuration(velocity, disp / mShiftRange);
     }
 
     public boolean animateToAllApps(AnimatorSet animationOut, long duration) {
@@ -511,21 +503,4 @@
         setProgress(mProgress);
     }
 
-    static class ScrollInterpolator implements Interpolator {
-
-        boolean mSteeper;
-
-        public void setVelocityAtZero(float velocity) {
-            mSteeper = velocity > FAST_FLING_PX_MS;
-        }
-
-        public float getInterpolation(float t) {
-            t -= 1.0f;
-            float output = t * t * t;
-            if (mSteeper) {
-                output *= t * t; // Make interpolation initial slope steeper
-            }
-            return output + 1;
-        }
-    }
 }
diff --git a/src/com/android/launcher3/allapps/VerticalPullDetector.java b/src/com/android/launcher3/allapps/VerticalPullDetector.java
index 96e1299..7800c01 100644
--- a/src/com/android/launcher3/allapps/VerticalPullDetector.java
+++ b/src/com/android/launcher3/allapps/VerticalPullDetector.java
@@ -4,6 +4,7 @@
 import android.util.Log;
 import android.view.MotionEvent;
 import android.view.ViewConfiguration;
+import android.view.animation.Interpolator;
 
 /**
  * One dimensional scroll gesture detector for all apps container pull up interaction.
@@ -23,6 +24,9 @@
     public static final int DIRECTION_DOWN = 1 << 1;
     public static final int DIRECTION_BOTH = DIRECTION_DOWN | DIRECTION_UP;
 
+    private static final float ANIMATION_DURATION = 1200;
+    private static final float FAST_FLING_PX_MS = 10;
+
     /**
      * The minimum release velocity in pixels per millisecond that triggers fling..
      */
@@ -112,7 +116,7 @@
         mListener = l;
     }
 
-    interface Listener {
+    public interface Listener {
         void onDragStart(boolean start);
 
         boolean onDrag(float displacement, float velocity);
@@ -272,4 +276,33 @@
     private static float interpolate(float from, float to, float alpha) {
         return (1.0f - alpha) * from + alpha * to;
     }
+
+    public long calculateDuration(float velocity, float progressNeeded) {
+        // TODO: make these values constants after tuning.
+        float velocityDivisor = Math.max(2f, Math.abs(0.5f * velocity));
+        float travelDistance = Math.max(0.2f, progressNeeded);
+        long duration = (long) Math.max(100, ANIMATION_DURATION / velocityDivisor * travelDistance);
+        if (DBG) {
+            Log.d(TAG, String.format("calculateDuration=%d, v=%f, d=%f", duration, velocity, progressNeeded));
+        }
+        return duration;
+    }
+
+    public static class ScrollInterpolator implements Interpolator {
+
+        boolean mSteeper;
+
+        public void setVelocityAtZero(float velocity) {
+            mSteeper = velocity > FAST_FLING_PX_MS;
+        }
+
+        public float getInterpolation(float t) {
+            t -= 1.0f;
+            float output = t * t * t;
+            if (mSteeper) {
+                output *= t * t; // Make interpolation initial slope steeper
+            }
+            return output + 1;
+        }
+    }
 }