Remove scrim on highlighted spring-loaded panel.

Bug: 27135377
Change-Id: I470955ed082a45ae7dc5f8fdd1f3decb2b573dbc

res/drawable/bg_celllayout.xml

@@ -22,13 +22,14 @@
 
     <item>
         <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" >
-            <solid android:color="#3fffffff" />
+            <solid android:color="@color/spring_loaded_panel_color" />
         </shape>
     </item>
     <item>
         <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" >
-            <solid android:color="#3fffffff" />
-            <stroke android:width="1dp" android:color="#fff" />
+            <stroke
+                android:width="@dimen/spring_loaded_panel_border"
+                android:color="@color/spring_loaded_highlighted_panel_border_color" />
         </shape>
     </item>
 

res/values/colors.xml

@@ -39,6 +39,9 @@
     <color name="outline_color">#FFFFFFFF</color>
     <color name="launcher_accent_color">#ff009688</color>
 
+    <color name="spring_loaded_panel_color">#40FFFFFF</color>
+    <color name="spring_loaded_highlighted_panel_border_color">#FFF</color>
+
     <!-- Containers -->
     <color name="container_fastscroll_thumb_inactive_color">#009688</color>
     <color name="container_fastscroll_thumb_active_color">#009688</color>

res/values/dimens.xml

@@ -134,6 +134,8 @@
 
     <dimen name="drag_flingToDeleteMinVelocity">-1500dp</dimen>
 
+    <dimen name="spring_loaded_panel_border">1dp</dimen>
+
 <!-- Theme -->
     <dimen name="quantum_panel_outer_padding">4dp</dimen>
 

src/com/android/launcher3/Hotseat.java

@@ -55,7 +55,7 @@ public class Hotseat extends FrameLayout
         mHasVerticalHotseat = mLauncher.getDeviceProfile().isVerticalBarLayout();
     }
 
-    CellLayout getLayout() {
+    public CellLayout getLayout() {
         return mContent;
     }
 

src/com/android/launcher3/PagedView.java

@@ -625,17 +625,23 @@ public abstract class PagedView extends ViewGroup implements ViewGroup.OnHierarc
 
     // we moved this functionality to a helper function so SmoothPagedView can reuse it
     protected boolean computeScrollHelper() {
+        return computeScrollHelper(true);
+    }
+
+    protected boolean computeScrollHelper(boolean shouldInvalidate) {
         if (mScroller.computeScrollOffset()) {
             // Don't bother scrolling if the page does not need to be moved
             if (getScrollX() != mScroller.getCurrX()
-                || getScrollY() != mScroller.getCurrY()) {
+                    || getScrollY() != mScroller.getCurrY()) {
                 float scaleX = mFreeScroll ? getScaleX() : 1f;
                 int scrollX = (int) (mScroller.getCurrX() * (1 / scaleX));
                 scrollTo(scrollX, mScroller.getCurrY());
             }
-            invalidate();
+            if (shouldInvalidate) {
+                invalidate();
+            }
             return true;
-        } else if (mNextPage != INVALID_PAGE) {
+        } else if (mNextPage != INVALID_PAGE && shouldInvalidate) {
             sendScrollAccessibilityEvent();
 
             mCurrentPage = validateNewPage(mNextPage);

src/com/android/launcher3/Workspace.java

@@ -149,7 +149,7 @@ public class Workspace extends PagedView
      */
     @Thunk CellLayout mDragTargetLayout = null;
     /**
-     * The CellLayout that we will show as glowing
+     * The CellLayout that we will show as highlighted
      */
     private CellLayout mDragOverlappingLayout = null;
 
@@ -1421,6 +1421,10 @@ public class Workspace extends PagedView
         mWallpaperOffset.syncWithScroll();
     }
 
+    public void computeScrollWithoutInvalidation() {
+        computeScrollHelper(false);
+    }
+
     @Override
     protected void determineScrollingStart(MotionEvent ev, float touchSlopScale) {
         if (!isSwitchingState()) {
@@ -2836,7 +2840,13 @@ public class Workspace extends PagedView
         if (mDragOverlappingLayout != null) {
             mDragOverlappingLayout.setIsDragOverlapping(true);
         }
-        invalidate();
+        // Invalidating the scrim will also force this CellLayout
+        // to be invalidated so that it is highlighted if necessary.
+        mLauncher.getDragLayer().invalidateScrim();
+    }
+
+    public CellLayout getCurrentDragOverlappingLayout() {
+        return mDragOverlappingLayout;
     }
 
     void setCurrentDropOverCell(int x, int y) {

src/com/android/launcher3/dragndrop/DragLayer.java

@@ -26,6 +26,7 @@ import android.content.res.Resources;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Rect;
+import android.graphics.Region;
 import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
 import android.view.DragEvent;
@@ -42,6 +43,7 @@ import android.widget.TextView;
 
 import com.android.launcher3.AppWidgetResizeFrame;
 import com.android.launcher3.CellLayout;
+import com.android.launcher3.Hotseat;
 import com.android.launcher3.InsettableFrameLayout;
 import com.android.launcher3.ItemInfo;
 import com.android.launcher3.Launcher;
@@ -92,6 +94,7 @@ public class DragLayer extends InsettableFrameLayout {
 
     private boolean mHoverPointClosesFolder = false;
     private final Rect mHitRect = new Rect();
+    private final Rect mHighlightRect = new Rect();
 
     private TouchCompleteListener mTouchCompleteListener;
 
@@ -922,12 +925,29 @@ public class DragLayer extends InsettableFrameLayout {
         invalidate();
     }
 
+    public void invalidateScrim() {
+        if (mBackgroundAlpha > 0.0f) {
+            invalidate();
+        }
+    }
+
     @Override
     protected void dispatchDraw(Canvas canvas) {
         // Draw the background below children.
         if (mBackgroundAlpha > 0.0f) {
+            // Update the scroll position first to ensure scrim cutout is in the right place.
+            mLauncher.getWorkspace().computeScrollWithoutInvalidation();
+
             int alpha = (int) (mBackgroundAlpha * 255);
+            CellLayout currCellLayout = mLauncher.getWorkspace().getCurrentDragOverlappingLayout();
+            canvas.save();
+            if (currCellLayout != null && currCellLayout != mLauncher.getHotseat().getLayout()) {
+                // Cut a hole in the darkening scrim on the page that should be highlighted, if any.
+                getDescendantRectRelativeToSelf(currCellLayout, mHighlightRect);
+                canvas.clipRect(mHighlightRect, Region.Op.DIFFERENCE);
+            }
             canvas.drawColor((alpha << 24) | SCRIM_COLOR);
+            canvas.restore();
         }
 
         super.dispatchDraw(canvas);