Merge changes from topic "am-d3d9c24b-dbc9-40e6-b12a-d4f1ff034e1e" into ub-launcher3-master
* changes:
[automerger] Settling scrolls over clear-all button. am: a9283beebc
Settling scrolls over clear-all button.
diff --git a/quickstep/src/com/android/quickstep/views/RecentsView.java b/quickstep/src/com/android/quickstep/views/RecentsView.java
index 6e70a55..7a04dcd 100644
--- a/quickstep/src/com/android/quickstep/views/RecentsView.java
+++ b/quickstep/src/com/android/quickstep/views/RecentsView.java
@@ -41,7 +41,6 @@
import android.util.ArraySet;
import android.util.AttributeSet;
import android.util.FloatProperty;
-import android.util.Log;
import android.util.SparseBooleanArray;
import android.view.KeyEvent;
import android.view.LayoutInflater;
@@ -315,52 +314,25 @@
final int childCount = getChildCount();
if (mShowEmptyMessage || childCount == 0) return 0;
- // Current visible coordinate of the end of the oldest task.
final View lastChild = getChildAt(childCount - 1);
+
+ // Current visible coordinate of the end of the oldest task.
final int carouselCurrentEnd =
(mIsRtl ? lastChild.getLeft() : lastChild.getRight()) - getScrollX();
- // As the end (let's call it E aka carouselCurrentEnd) of the carousel moves over Clear
- // all button, the button changes trasparency.
- // fullAlphaX and zeroAlphaX are the points of the 100% and 0% alpha correspondingly.
- // Alpha changes linearly between 100% and 0% as E moves through this range. It doesn't
- // change outside of the range.
+ // Visible button-facing end of a centered task.
+ final int centeredTaskEnd = mIsRtl ?
+ getPaddingLeft() + mInsets.left :
+ getWidth() - getPaddingRight() - mInsets.right;
- // Once E hits the border of the Clear-All button that looks towards the most recent
- // task, the whole button is uncovered, and it should have alpha 100%.
- final float fullAlphaX = mIsRtl ?
- mClearAllButton.getX() + mClearAllButton.getWidth() :
- mClearAllButton.getX();
-
- // X coordinate of the carousel scrolled as far as possible in the direction towards the
- // button. Logically, the button is "behind" the least recent task. This is the
- // coordinate of the end of the least recent task in the carousel just after opening,
- // with the most recent task in the center, and the rest of tasks go from that point
- // towards and potentially behind the button.
- final int carouselMotionLimit = getScrollForPage(childCount - 1) - getScrollForPage(0) +
- (mIsRtl ?
- getPaddingLeft() + mInsets.left :
- getWidth() - getPaddingRight() - mInsets.right);
-
- // The carousel might not be able to ever cover a part of the Clear-all button. Then
- // always show the button as 100%. Technically, this check also prevents dividing by zero
- // or getting a negative transparency ratio.
- if (mIsRtl ? carouselMotionLimit >= fullAlphaX : carouselMotionLimit <= fullAlphaX) {
- return 1;
- }
-
- // If the carousel is able to cover the button completely, we make the button completely
- // transparent when E hits the border of the button farthest from the most recent task.
- // Or, the carousel may not be able to move that far towards the button so it completely
- // covers the it. Then we set the motion limit position of the carousel as the point
- // where the button reaches 0 alpha.
- final float zeroAlphaX = mIsRtl ?
- Math.max(mClearAllButton.getX(), carouselMotionLimit) :
- Math.min(mClearAllButton.getX() + mClearAllButton.getWidth(), carouselMotionLimit);
+ // The distance of the carousel travel during which the alpha changes from 0 to 1. This
+ // is the motion between the oldest task in its centered position and the oldest task
+ // scrolled to the end.
+ final int alphaChangeRange = (mIsRtl ? 0 : mMaxScrollX) - getScrollForPage(childCount - 1);
return Utilities.boundToRange(
- (zeroAlphaX - carouselCurrentEnd) /
- (zeroAlphaX - fullAlphaX), 0, 1);
+ ((float) (centeredTaskEnd - carouselCurrentEnd)) /
+ alphaChangeRange, 0, 1);
}
private void updateClearAllButtonAlpha() {