DO NOT MERGE Overscroll continues; asset and behavior tweaks.

Change-Id: I367643877a397e7b4fa9bd8c40639ff69436e7f0

4 files changed, 57 insertions, 25 deletions

diff --git a/core/java/android/widget/AbsListView.java b/core/java/android/widget/AbsListView.java
index db50ca15adc4..fe2a43b7abe2 100644
--- a/core/java/android/widget/AbsListView.java
+++ b/core/java/android/widget/AbsListView.java
@@ -507,6 +507,20 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
     private EdgeGlow mEdgeGlowBottom;
 
     /**
+     * An estimate of how many pixels are between the top of the list and
+     * the top of the first position in the adapter, based on the last time
+     * we saw it. Used to hint where to draw edge glows.
+     */
+    private int mFirstPositionDistanceGuess;
+
+    /**
+     * An estimate of how many pixels are between the bottom of the list and
+     * the bottom of the last position in the adapter, based on the last time
+     * we saw it. Used to hint where to draw edge glows.
+     */
+    private int mLastPositionDistanceGuess;
+
+    /**
      * Interface definition for a callback to be invoked when the list or grid
      * has been scrolled.
      */
@@ -632,7 +646,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
         if (mode != OVERSCROLL_NEVER) {
             if (mEdgeGlowTop == null) {
                 final Resources res = getContext().getResources();
-                final Drawable edge = res.getDrawable(R.drawable.edge_light);
+                final Drawable edge = res.getDrawable(R.drawable.overscroll_edge);
                 final Drawable glow = res.getDrawable(R.drawable.overscroll_glow);
                 mEdgeGlowTop = new EdgeGlow(edge, glow);
                 mEdgeGlowBottom = new EdgeGlow(edge, glow);
@@ -1684,6 +1698,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
                 mFlingRunnable.endFling();
                 if (mScrollY != 0) {
                     mScrollY = 0;
+                    finishGlows();
                     invalidate();
                 }
             }
@@ -2041,6 +2056,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
 
                 if (mScrollY != 0) {
                     mScrollY = 0;
+                    finishGlows();
                     invalidate();
                 }
             }
@@ -2518,7 +2534,7 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
                 final int restoreCount = canvas.save();
                 final int width = getWidth();
 
-                canvas.translate(-width / 2, scrollY);
+                canvas.translate(-width / 2, Math.min(0, scrollY + mFirstPositionDistanceGuess));
                 mEdgeGlowTop.setSize(width * 2, getHeight());
                 if (mEdgeGlowTop.draw(canvas)) {
                     invalidate();
@@ -2530,7 +2546,8 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
                 final int width = getWidth();
                 final int height = getHeight();
 
-                canvas.translate(-width / 2, scrollY + height);
+                canvas.translate(-width / 2,
+                        Math.max(height, scrollY + mLastPositionDistanceGuess));
                 canvas.rotate(180, width, 0);
                 mEdgeGlowBottom.setSize(width * 2, height);
                 if (mEdgeGlowBottom.draw(canvas)) {
@@ -3223,6 +3240,18 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
 
         final int firstPosition = mFirstPosition;
 
+        // Update our guesses for where the first and last views are
+        if (firstPosition == 0) {
+            mFirstPositionDistanceGuess = firstTop - mListPadding.top;
+        } else {
+            mFirstPositionDistanceGuess += incrementalDeltaY;
+        }
+        if (firstPosition + childCount == mItemCount) {
+            mLastPositionDistanceGuess = lastBottom + mListPadding.bottom;
+        } else {
+            mLastPositionDistanceGuess += incrementalDeltaY;
+        }
+
         if (firstPosition == 0 && firstTop >= listPadding.top && incrementalDeltaY >= 0) {
             // Don't need to move views down if the top of the first position
             // is already visible
@@ -4167,6 +4196,13 @@ public abstract class AbsListView extends AdapterView<ListAdapter> implements Te
         return result;
     }
 
+    private void finishGlows() {
+        if (mEdgeGlowTop != null) {
+            mEdgeGlowTop.finish();
+            mEdgeGlowBottom.finish();
+        }
+    }
+
     /**
      * Sets the recycler listener to be notified whenever a View is set aside in
      * the recycler for later reuse. This listener can be used to free resources
diff --git a/core/java/android/widget/EdgeGlow.java b/core/java/android/widget/EdgeGlow.java
index 06334a06f8b8..93222e1c00fc 100644
--- a/core/java/android/widget/EdgeGlow.java
+++ b/core/java/android/widget/EdgeGlow.java
@@ -18,7 +18,6 @@ package android.widget;
 
 import android.graphics.Canvas;
 import android.graphics.drawable.Drawable;
-import android.util.Log;
 import android.view.animation.AnimationUtils;
 import android.view.animation.DecelerateInterpolator;
 import android.view.animation.Interpolator;
@@ -30,8 +29,6 @@ import android.view.animation.Interpolator;
 public class EdgeGlow {
     private static final String TAG = "EdgeGlow";
 
-    private static final boolean DEBUG = false;
-
     // Time it will take the effect to fully recede in ms
     private static final int RECEDE_TIME = 1000;
 
@@ -46,7 +43,10 @@ public class EdgeGlow {
     private static final float HELD_GLOW_ALPHA = 0.5f;
     private static final float HELD_GLOW_SCALE_Y = 0.5f;
 
+    private static final float MAX_GLOW_HEIGHT = 0.33f;
+
     private static final float PULL_GLOW_BEGIN = 0.5f;
+    private static final float PULL_EDGE_BEGIN = 0.6f;
 
     // Minimum velocity that will be absorbed
     private static final int MIN_VELOCITY = 750;
@@ -103,6 +103,10 @@ public class EdgeGlow {
         return mState == STATE_IDLE;
     }
 
+    public void finish() {
+        mState = STATE_IDLE;
+    }
+
     /**
      * Call when the object is pulled by the user.
      * @param deltaDistance Change in distance since the last call
@@ -123,7 +127,7 @@ public class EdgeGlow {
         mPullDistance += deltaDistance;
         float distance = Math.abs(mPullDistance);
 
-        mEdgeAlpha = mEdgeAlphaStart = Math.max(HELD_EDGE_ALPHA, Math.min(distance, 1.f));
+        mEdgeAlpha = mEdgeAlphaStart = Math.max(PULL_EDGE_BEGIN, Math.min(distance, 1.f));
         mEdgeScaleY = mEdgeScaleYStart = Math.max(HELD_EDGE_SCALE_Y, Math.min(distance, 2.f));
 
         mGlowAlpha = mGlowAlphaStart = Math.max(0.5f,
@@ -142,8 +146,6 @@ public class EdgeGlow {
         mEdgeScaleYFinish = mEdgeScaleY;
         mGlowAlphaFinish = mGlowAlpha;
         mGlowScaleYFinish = mGlowScaleY;
-
-        if (DEBUG) Log.d(TAG, "onPull(" + distance + ", " + deltaDistance + ")");
     }
 
     /**
@@ -155,7 +157,6 @@ public class EdgeGlow {
         if (mState != STATE_PULL && mState != STATE_PULL_DECAY) {
             return;
         }
-        if (DEBUG) Log.d(TAG, "onRelease");
 
         mState = STATE_RECEDE;
         mEdgeAlphaStart = mEdgeAlpha;
@@ -178,7 +179,6 @@ public class EdgeGlow {
      */
     public void onAbsorb(int velocity) {
         mState = STATE_ABSORB;
-        if (DEBUG) Log.d(TAG, "onAbsorb uncooked velocity: " + velocity);
         velocity = Math.max(MIN_VELOCITY, Math.abs(velocity));
 
         mStartTime = AnimationUtils.currentAnimationTimeMillis();
@@ -193,8 +193,6 @@ public class EdgeGlow {
         mEdgeScaleYFinish = 1.f;
         mGlowAlphaFinish = 1.f;
         mGlowScaleYFinish = Math.min(velocity * 0.001f, 1);
-
-        if (DEBUG) Log.d(TAG, "onAbsorb(" + velocity + "): duration " + mDuration);
     }
 
     /**
@@ -212,8 +210,11 @@ public class EdgeGlow {
         final int edgeHeight = mEdge.getIntrinsicHeight();
         final int glowHeight = mGlow.getIntrinsicHeight();
 
+        final float distScale = (float) mHeight / mWidth;
+
         mGlow.setAlpha((int) (Math.max(0, Math.min(mGlowAlpha, 1)) * 255));
-        mGlow.setBounds(0, 0, mWidth, (int) (glowHeight * mGlowScaleY * 0.5f));
+        mGlow.setBounds(0, 0, mWidth, (int) Math.min(glowHeight * mGlowScaleY * distScale * 0.6f,
+                mHeight * MAX_GLOW_HEIGHT));
         mGlow.draw(canvas);
 
         mEdge.setAlpha((int) (Math.max(0, Math.min(mEdgeAlpha, 1)) * 255));
@@ -222,8 +223,6 @@ public class EdgeGlow {
                 mWidth,
                 (int) (edgeHeight * mEdgeScaleY));
         mEdge.draw(canvas);
-        if (DEBUG) Log.d(TAG, "draw() glow(" + mGlowAlpha + ", " + mGlowScaleY + ") edge(" + mEdgeAlpha +
-                ", " + mEdgeScaleY + ")");
 
         return mState != STATE_IDLE;
     }
@@ -255,7 +254,6 @@ public class EdgeGlow {
                     mEdgeScaleYFinish = 0.1f;
                     mGlowAlphaFinish = 0.f;
                     mGlowScaleYFinish = mGlowScaleY;
-                    if (DEBUG) Log.d(TAG, "STATE_ABSORB => STATE_RECEDE");
                     break;
                 case STATE_PULL:
                     mState = STATE_PULL_DECAY;
@@ -271,14 +269,12 @@ public class EdgeGlow {
                     mEdgeScaleYFinish = Math.min(mEdgeScaleYStart, HELD_EDGE_SCALE_Y);
                     mGlowAlphaFinish = Math.min(mGlowAlphaStart, HELD_GLOW_ALPHA);
                     mGlowScaleYFinish = Math.min(mGlowScaleY, HELD_GLOW_SCALE_Y);
-                    if (DEBUG) Log.d(TAG, "STATE_PULL => STATE_PULL_DECAY");
                     break;
                 case STATE_PULL_DECAY:
                     // Do nothing; wait for release
                     break;
                 case STATE_RECEDE:
                     mState = STATE_IDLE;
-                    if (DEBUG) Log.d(TAG, "STATE_RECEDE => STATE_IDLE");
                     break;
             }
         }
diff --git a/core/java/android/widget/HorizontalScrollView.java b/core/java/android/widget/HorizontalScrollView.java
index 3493f498caa8..129ad8ac64ed 100644
--- a/core/java/android/widget/HorizontalScrollView.java
+++ b/core/java/android/widget/HorizontalScrollView.java
@@ -1374,7 +1374,7 @@ public class HorizontalScrollView extends FrameLayout {
         if (mode != OVERSCROLL_NEVER) {
             if (mEdgeGlowLeft == null) {
                 final Resources res = getContext().getResources();
-                final Drawable edge = res.getDrawable(R.drawable.edge_light);
+                final Drawable edge = res.getDrawable(R.drawable.overscroll_edge);
                 final Drawable glow = res.getDrawable(R.drawable.overscroll_glow);
                 mEdgeGlowLeft = new EdgeGlow(edge, glow);
                 mEdgeGlowRight = new EdgeGlow(edge, glow);
@@ -1396,7 +1396,7 @@ public class HorizontalScrollView extends FrameLayout {
                 final int height = getHeight();
 
                 canvas.rotate(270);
-                canvas.translate(-height * 1.5f, scrollX);
+                canvas.translate(-height * 1.5f, Math.min(0, scrollX));
                 mEdgeGlowLeft.setSize(getHeight() * 2, getWidth());
                 if (mEdgeGlowLeft.draw(canvas)) {
                     invalidate();
@@ -1409,7 +1409,7 @@ public class HorizontalScrollView extends FrameLayout {
                 final int height = getHeight();
 
                 canvas.rotate(90);
-                canvas.translate(-height / 2, -scrollX - width);
+                canvas.translate(-height / 2, -(Math.max(getScrollRange(), scrollX) + width));
                 mEdgeGlowRight.setSize(height * 2, width);
                 if (mEdgeGlowRight.draw(canvas)) {
                     invalidate();
diff --git a/core/java/android/widget/ScrollView.java b/core/java/android/widget/ScrollView.java
index 9d971f6b213f..7b5e4125eca8 100644
--- a/core/java/android/widget/ScrollView.java
+++ b/core/java/android/widget/ScrollView.java
@@ -1374,7 +1374,7 @@ public class ScrollView extends FrameLayout {
         if (mode != OVERSCROLL_NEVER) {
             if (mEdgeGlowTop == null) {
                 final Resources res = getContext().getResources();
-                final Drawable edge = res.getDrawable(R.drawable.edge_light);
+                final Drawable edge = res.getDrawable(R.drawable.overscroll_edge);
                 final Drawable glow = res.getDrawable(R.drawable.overscroll_glow);
                 mEdgeGlowTop = new EdgeGlow(edge, glow);
                 mEdgeGlowBottom = new EdgeGlow(edge, glow);
@@ -1395,7 +1395,7 @@ public class ScrollView extends FrameLayout {
                 final int restoreCount = canvas.save();
                 final int width = getWidth();
 
-                canvas.translate(-width / 2, scrollY);
+                canvas.translate(-width / 2, Math.min(0, scrollY));
                 mEdgeGlowTop.setSize(width * 2, getHeight());
                 if (mEdgeGlowTop.draw(canvas)) {
                     invalidate();
@@ -1407,7 +1407,7 @@ public class ScrollView extends FrameLayout {
                 final int width = getWidth();
                 final int height = getHeight();
 
-                canvas.translate(-width / 2, scrollY + height);
+                canvas.translate(-width / 2, Math.max(getScrollRange(), scrollY) + height);
                 canvas.rotate(180, width, 0);
                 mEdgeGlowBottom.setSize(width * 2, height);
                 if (mEdgeGlowBottom.draw(canvas)) {