Working around incorrect wallpaper offsets being calculated in RTL.

- When launcher starts up, onCreate() triggers the launcher model loader
  to start, which calls bindScreens() to add the workspace pages.  
  However, layout does not happen until the device is unlocked, which 
  means that even though the default screen index and children are there
  the page scrolls are calculated incorrectly, and even in RTL, the 
  page scroll for the 0th screen is zero (it should be at the right
  most edge of the workspace).  This CL works around this by deferring 
  until the first layout after bindScreens() to unlock the wallpaper
  offset from its default bounds.  The workaround is only applied when 
  the launcher activity is first created.

Bug: 28795125
Change-Id: I33da0d7f934f5337d26e69f068f579a32897a837

1 files changed, 16 insertions, 1 deletions

diff --git a/src/com/android/launcher3/Workspace.java b/src/com/android/launcher3/Workspace.java
index 3c057e6fd..264da04d8 100644
--- a/src/com/android/launcher3/Workspace.java
+++ b/src/com/android/launcher3/Workspace.java
@@ -90,7 +90,6 @@ import com.android.launcher3.widget.PendingAddWidgetInfo;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
-import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * The workspace is a wide area with a wallpaper and a finite number of pages.
@@ -253,6 +252,7 @@ public class Workspace extends PagedView
     private boolean mWorkspaceFadeInAdjacentScreens;
 
     final WallpaperOffsetInterpolator mWallpaperOffset;
+    private boolean mUnlockWallpaperFromDefaultPageOnLayout;
 
     @Thunk Runnable mDelayedResizeRunnable;
     private Runnable mDelayedSnapToPageRunnable;
@@ -1616,6 +1616,17 @@ public class Workspace extends PagedView
         });
     }
 
+    public void lockWallpaperToDefaultPage() {
+        mWallpaperOffset.setLockToDefaultPage(true);
+    }
+
+    public void unlockWallpaperFromDefaultPageOnNextLayout() {
+        if (mWallpaperOffset.isLockedToDefaultPage()) {
+            mUnlockWallpaperFromDefaultPageOnLayout = true;
+            requestLayout();
+        }
+    }
+
     protected void snapToPage(int whichPage, Runnable r) {
         snapToPage(whichPage, SLOW_PAGE_SNAP_ANIMATION_DURATION, r);
     }
@@ -1797,6 +1808,10 @@ public class Workspace extends PagedView
 
     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+        if (mUnlockWallpaperFromDefaultPageOnLayout) {
+            mWallpaperOffset.setLockToDefaultPage(false);
+            mUnlockWallpaperFromDefaultPageOnLayout = false;
+        }
         if (mFirstLayout && mCurrentPage >= 0 && mCurrentPage < getChildCount()) {
             mWallpaperOffset.syncWithScroll();
             mWallpaperOffset.jumpToFinal();