Stop jumping to workspace from hotseat on quick drop.

Regression occurred in ag/1315317.

In that change, Launcher#enterSpringLoadedDragMode() was moved from
the end of startDrag() to the end of onDragStart(). This changed the
sequence of events from:

beginDragShared() --> DragController#startDrag() --> onDragStart -->
dropTarget.onDragOver() --> Launcher#enterSpringLoadedDragMode()

to:

beginDragShared() --> DragController#startDrag() --> onDragStart -->
Launcher#enterSpringLoadedDragMode() --> onDragOver()

Basically, the key difference is that onDragOver() is called after
enterSpringLoadedDragMode(). This matters, because onDragOver()
returns early if Workspace#transitionStateShouldAllowDrop() returns
false, which it does during the spring loaded transition. This meant
that onDragOver() didn't update the layout to be Hotseat, and thus
the current workspace page was used as default, since that is what
was set in onDragEnter(). To fix it, I've copied the logic in
onDragOver() that checks to see if the drag is over the hotseat first
to a new method that onDragEnter() now calls as well.

Bug: 31245181
Change-Id: Ie758921b25fc96516a09c32bdc9706da941522df

1 files changed, 42 insertions, 41 deletions

diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index c499beeb3..0e25b1ef9 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -25,7 +25,6 @@ import android.animation.PropertyValuesHolder;
 import android.animation.ValueAnimator;
 import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.annotation.SuppressLint;
-import android.annotation.TargetApi;
 import android.app.WallpaperManager;
 import android.appwidget.AppWidgetHostView;
 import android.appwidget.AppWidgetProviderInfo;
@@ -39,7 +38,6 @@ import android.graphics.Point;
 import android.graphics.PointF;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
-import android.os.Build;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Parcelable;
@@ -2800,9 +2798,7 @@ public class Workspace extends PagedView
         mAddToExistingFolderOnDrop = false;
 
         mDropToLayout = null;
-        CellLayout layout = getCurrentDropLayout();
-        setCurrentDropLayout(layout);
-        setCurrentDragOverlappingLayout(layout);
+        setDropLayoutForDragObject(d);
 
         if (!workspaceInModalState() && FeatureFlags.LAUNCHER3_LEGACY_WORKSPACE_DND) {
             mLauncher.getDragLayer().showPageHints();
@@ -3061,7 +3057,6 @@ public class Workspace extends PagedView
         // Skip drag over events while we are dragging over side pages
         if (mInScrollArea || !transitionStateShouldAllowDrop()) return;
 
-        CellLayout layout = null;
         ItemInfo item = d.dragInfo;
         if (item == null) {
             if (ProviderConfig.IS_DOGFOOD_BUILD) {
@@ -3075,43 +3070,15 @@ public class Workspace extends PagedView
         mDragViewVisualCenter = d.getVisualCenter(mDragViewVisualCenter);
 
         final View child = (mDragInfo == null) ? null : mDragInfo.cell;
-        // Identify whether we have dragged over a side page
-        if (workspaceInModalState()) {
-            if (mLauncher.getHotseat() != null && !isDragWidget(d)) {
-                if (isPointInSelfOverHotseat(d.x, d.y)) {
-                    layout = mLauncher.getHotseat().getLayout();
-                }
-            }
-            if (layout == null) {
-                layout = findMatchingPageForDragOver(d.dragView, d.x, d.y, false);
-            }
-            if (layout != mDragTargetLayout) {
-                setCurrentDropLayout(layout);
-                setCurrentDragOverlappingLayout(layout);
-
-                boolean isInSpringLoadedMode = (mState == State.SPRING_LOADED);
-                if (isInSpringLoadedMode) {
-                    if (mLauncher.isHotseatLayout(layout)) {
-                        mSpringLoadedDragController.cancel();
-                    } else {
-                        mSpringLoadedDragController.setAlarm(mDragTargetLayout);
-                    }
-                }
-            }
-        } else {
-            // Test to see if we are over the hotseat otherwise just use the current page
-            if (mLauncher.getHotseat() != null && !isDragWidget(d)) {
-                if (isPointInSelfOverHotseat(d.x, d.y)) {
-                    layout = mLauncher.getHotseat().getLayout();
+        if (setDropLayoutForDragObject(d)) {
+            boolean isInSpringLoadedMode = (mState == State.SPRING_LOADED);
+            if (isInSpringLoadedMode) {
+                if (mLauncher.isHotseatLayout(mDragTargetLayout)) {
+                    mSpringLoadedDragController.cancel();
+                } else {
+                    mSpringLoadedDragController.setAlarm(mDragTargetLayout);
                 }
             }
-            if (layout == null) {
-                layout = getCurrentDropLayout();
-            }
-            if (layout != mDragTargetLayout) {
-                setCurrentDropLayout(layout);
-                setCurrentDragOverlappingLayout(layout);
-            }
         }
 
         // Handle the drag over
@@ -3176,6 +3143,40 @@ public class Workspace extends PagedView
         }
     }
 
+    /**
+     * Updates {@link #mDragTargetLayout} and {@link #mDragOverlappingLayout}
+     * based on the DragObject's position.
+     *
+     * The layout will be:
+     * - The Hotseat if the drag object is over it
+     * - A side page if we are in spring-loaded mode and the drag object is over it
+     * - The current page otherwise
+     *
+     * @return whether the layout is different from the current {@link #mDragTargetLayout}.
+     */
+    private boolean setDropLayoutForDragObject(DragObject d) {
+        CellLayout layout = null;
+        // Test to see if we are over the hotseat first
+        if (mLauncher.getHotseat() != null && !isDragWidget(d)) {
+            if (isPointInSelfOverHotseat(d.x, d.y)) {
+                layout = mLauncher.getHotseat().getLayout();
+            }
+        }
+        if (layout == null) {
+            // Identify whether we have dragged over a side page,
+            // otherwise just use the current page
+            layout = workspaceInModalState() ?
+                    findMatchingPageForDragOver(d.dragView, d.x, d.y, false)
+                    : getCurrentDropLayout();
+        }
+        if (layout != mDragTargetLayout) {
+            setCurrentDropLayout(layout);
+            setCurrentDragOverlappingLayout(layout);
+            return true;
+        }
+        return false;
+    }
+
     private void manageFolderFeedback(CellLayout targetLayout,
             int[] targetCell, float distance, DragObject dragObject) {
         if (distance > mMaxDistanceForFolderCreation) return;