commit c6d3ac2385b42e1bc939313a4283e8d28db477b3
author Matt Pietal <mpietal@google.com> Thu Apr 25 14:38:30 2019 -0400
committer Matt Pietal <mpietal@google.com> Thu Apr 25 14:42:19 2019 -0400
tree 5843b0adf5512440251864b5225e83d09c20c46d
parent 22f79f250ca06385340bb7be2e7a274538d399e5

Sharesheet - Modify header scrolling behavior

To align with UX, scroll the listview before the header when
collapsing the sharesheet to its minified state, on both flings and
drags. Fix an issue with the expansion area, whereby state is only
updated if view positions are actually updated.

Bug: 129979914
Test: Visual inspection
Change-Id: I2e32a1a3288a21bcd3ce07819f77760f10d5d929

core/java/com/android/internal/app/ChooserActivity.java

diff --git a/core/java/com/android/internal/app/ChooserActivity.java b/core/java/com/android/internal/app/ChooserActivity.java
index ca2bc7f..26e47fd 100644
--- a/core/java/com/android/internal/app/ChooserActivity.java
+++ b/core/java/com/android/internal/app/ChooserActivity.java
@@ -3042,10 +3042,9 @@
             int yDiff = (int) ((oldy - y) * DIRECT_SHARE_EXPANSION_RATE);
 
             int prevHeight = mDirectShareCurrHeight;
-            mDirectShareCurrHeight = Math.min(mDirectShareCurrHeight + yDiff,
-                    mDirectShareMaxHeight);
-            mDirectShareCurrHeight = Math.max(mDirectShareCurrHeight, mDirectShareMinHeight);
-            yDiff = mDirectShareCurrHeight - prevHeight;
+            int newHeight = Math.min(prevHeight + yDiff, mDirectShareMaxHeight);
+            newHeight = Math.max(newHeight, mDirectShareMinHeight);
+            yDiff = newHeight - prevHeight;
 
             if (view == null || view.getChildCount() == 0 || yDiff == 0) {
                 return;
@@ -3062,7 +3061,7 @@
                     if (child.getTag() != null && child.getTag() instanceof DirectShareViewHolder) {
                         int widthSpec = MeasureSpec.makeMeasureSpec(child.getWidth(),
                                 MeasureSpec.EXACTLY);
-                        int heightSpec = MeasureSpec.makeMeasureSpec(mDirectShareCurrHeight,
+                        int heightSpec = MeasureSpec.makeMeasureSpec(newHeight,
                                 MeasureSpec.EXACTLY);
                         child.measure(widthSpec, heightSpec);
                         child.getLayoutParams().height = child.getMeasuredHeight();
@@ -3073,6 +3072,10 @@
                     }
                 }
             }
+
+            if (foundExpansion) {
+                mDirectShareCurrHeight = newHeight;
+            }
         }
     }
 

core/java/com/android/internal/widget/ResolverDrawerLayout.java

diff --git a/core/java/com/android/internal/widget/ResolverDrawerLayout.java b/core/java/com/android/internal/widget/ResolverDrawerLayout.java
index 66bbe22..6b0d85e 100644
--- a/core/java/com/android/internal/widget/ResolverDrawerLayout.java
+++ b/core/java/com/android/internal/widget/ResolverDrawerLayout.java
@@ -114,6 +114,8 @@
 
     private final Rect mTempRect = new Rect();
 
+    private AbsListView mNestedScrollingChild;
+
     private final ViewTreeObserver.OnTouchModeChangeListener mTouchModeChangeListener =
             new ViewTreeObserver.OnTouchModeChangeListener() {
                 @Override
@@ -317,6 +319,13 @@
         return mIsDragging || mOpenOnClick;
     }
 
+    private boolean isNestedChildScrolled() {
+        return mNestedScrollingChild != null
+                && mNestedScrollingChild.getChildCount() > 0
+                && (mNestedScrollingChild.getFirstVisiblePosition() > 0
+                        || mNestedScrollingChild.getChildAt(0).getTop() < 0);
+    }
+
     @Override
     public boolean onTouchEvent(MotionEvent ev) {
         final int action = ev.getActionMasked();
@@ -359,7 +368,11 @@
                 }
                 if (mIsDragging) {
                     final float dy = y - mLastTouchY;
-                    performDrag(dy);
+                    if (dy > 0 && isNestedChildScrolled()) {
+                        mNestedScrollingChild.smoothScrollBy((int) -dy, 0);
+                    } else {
+                        performDrag(dy);
+                    }
                 }
                 mLastTouchY = y;
             }
@@ -411,6 +424,9 @@
                             smoothScrollTo(mCollapsibleHeight + mUncollapsibleHeight, yvel);
                             mDismissOnScrollerFinished = true;
                         } else {
+                            if (isNestedChildScrolled()) {
+                                mNestedScrollingChild.smoothScrollToPosition(0);
+                            }
                             smoothScrollTo(yvel < 0 ? 0 : mCollapsibleHeight, yvel);
                         }
                     }
@@ -680,7 +696,13 @@
 
     @Override
     public boolean onStartNestedScroll(View child, View target, int nestedScrollAxes) {
-        return (nestedScrollAxes & View.SCROLL_AXIS_VERTICAL) != 0;
+        if ((nestedScrollAxes & View.SCROLL_AXIS_VERTICAL) != 0) {
+            if (child instanceof AbsListView) {
+                mNestedScrollingChild = (AbsListView) child;
+            }
+            return true;
+        }
+        return false;
     }
 
     @Override