Fix issue #5371530: SYSTEMUI_FLAG_HIDE_NAVIGATION reasserts itself immediately

This cleans up how ui flags are managed between the client and window manager.
It still reports the global UI mode state to the callback, but we now only clear
certain flags when the system goes out of a state (currently this just means the
hide nav bar mode), and don't corrupt other flags in the application when the
global state changes.

Also introduces a sequence number between the app and window manager, to avoid
using bad old data coming from the app during these transitions.

Change-Id: I40bbd12d9b7b69fc0ff1c7dc0cb58a933d4dfb23

Author: Dianne Hackborn

core/java/android/service/wallpaper/WallpaperService.java

@@ -565,7 +565,7 @@ void updateSurface(boolean forceRelayout, boolean forceReport, boolean redrawNee
                         mLayout.windowAnimations =
                                 com.android.internal.R.style.Animation_Wallpaper;
                         mInputChannel = new InputChannel();
-                        if (mSession.add(mWindow, mLayout, View.VISIBLE, mContentInsets,
+                        if (mSession.add(mWindow, mWindow.mSeq, mLayout, View.VISIBLE, mContentInsets,
                                 mInputChannel) < 0) {
                             Log.w(TAG, "Failed to add window while updating wallpaper surface.");
                             return;
@@ -580,7 +580,7 @@ void updateSurface(boolean forceRelayout, boolean forceReport, boolean redrawNee
                     mDrawingAllowed = true;
 
                     final int relayoutResult = mSession.relayout(
-                        mWindow, mLayout, mWidth, mHeight,
+                        mWindow, mWindow.mSeq, mLayout, mWidth, mHeight,
                             View.VISIBLE, false, mWinFrame, mContentInsets,
                             mVisibleInsets, mConfiguration, mSurfaceHolder.mSurface);
 

core/java/android/view/IWindow.aidl

@@ -74,5 +74,6 @@ oneway interface IWindow {
     /**
      * System chrome visibility changes
      */
-     void dispatchSystemUiVisibilityChanged(int visibility);
+     void dispatchSystemUiVisibilityChanged(int seq, int globalVisibility,
+            int localValue, int localChanges);
 }

core/java/android/view/IWindowSession.aidl

@@ -34,10 +34,10 @@ import android.view.Surface;
  * {@hide}
  */
 interface IWindowSession {
-    int add(IWindow window, in WindowManager.LayoutParams attrs,
+    int add(IWindow window, int seq, in WindowManager.LayoutParams attrs,
             in int viewVisibility, out Rect outContentInsets,
             out InputChannel outInputChannel);
-    int addWithoutInputChannel(IWindow window, in WindowManager.LayoutParams attrs,
+    int addWithoutInputChannel(IWindow window, int seq, in WindowManager.LayoutParams attrs,
             in int viewVisibility, out Rect outContentInsets);
     void remove(IWindow window);
 
@@ -49,6 +49,7 @@ interface IWindowSession {
      * to draw the window's contents.
      * 
      * @param window The window being modified.
+     * @param seq Ordering sequence number.
      * @param attrs If non-null, new attributes to apply to the window.
      * @param requestedWidth The width the window wants to be.
      * @param requestedHeight The height the window wants to be.
@@ -77,7 +78,7 @@ interface IWindowSession {
      * @return int Result flags: {@link WindowManagerImpl#RELAYOUT_SHOW_FOCUS},
      * {@link WindowManagerImpl#RELAYOUT_FIRST_TIME}.
      */
-    int relayout(IWindow window, in WindowManager.LayoutParams attrs,
+    int relayout(IWindow window, int seq, in WindowManager.LayoutParams attrs,
             int requestedWidth, int requestedHeight, int viewVisibility,
             boolean insetsPending, out Rect outFrame, out Rect outContentInsets,
             out Rect outVisibleInsets, out Configuration outConfig,

core/java/android/view/SurfaceView.java

@@ -266,7 +266,7 @@ protected void hideSurface() {
             try {
                 DisplayMetrics metrics = getResources().getDisplayMetrics();
                 mLayout.x = metrics.widthPixels * 3;
-                mSession.relayout(mWindow, mLayout, mWidth, mHeight, VISIBLE, false,
+                mSession.relayout(mWindow, mWindow.mSeq, mLayout, mWidth, mHeight, VISIBLE, false,
                         mWinFrame, mContentInsets, mVisibleInsets, mConfiguration, mSurface);
             } catch (RemoteException e) {
                 // Ignore
@@ -492,7 +492,7 @@ private void updateWindow(boolean force, boolean redrawNeeded) {
                     mWindow = new MyWindow(this);
                     mLayout.type = mWindowType;
                     mLayout.gravity = Gravity.LEFT|Gravity.TOP;
-                    mSession.addWithoutInputChannel(mWindow, mLayout,
+                    mSession.addWithoutInputChannel(mWindow, mWindow.mSeq, mLayout,
                             mVisible ? VISIBLE : GONE, mContentInsets);
                 }
 
@@ -513,7 +513,7 @@ private void updateWindow(boolean force, boolean redrawNeeded) {
                     mDrawingStopped = !visible;
 
                     final int relayoutResult = mSession.relayout(
-                        mWindow, mLayout, mWidth, mHeight,
+                        mWindow, mWindow.mSeq, mLayout, mWidth, mHeight,
                             visible ? VISIBLE : GONE, false, mWinFrame, mContentInsets,
                             mVisibleInsets, mConfiguration, mSurface);
                     if ((relayoutResult&WindowManagerImpl.RELAYOUT_FIRST_TIME) != 0) {

core/java/android/view/View.java

@@ -1924,6 +1924,15 @@ public class View implements Drawable.Callback, Drawable.Callback2, KeyEvent.Cal
      */
     public static final int PUBLIC_STATUS_BAR_VISIBILITY_MASK = 0x0000FFFF;
 
+    /**
+     * These are the system UI flags that can be cleared by events outside
+     * of an application.  Currently this is just the ability to tap on the
+     * screen while hiding the navigation bar to have it return.
+     * @hide
+     */
+    public static final int SYSTEM_UI_CLEARABLE_FLAGS =
+            SYSTEM_UI_FLAG_LOW_PROFILE | SYSTEM_UI_FLAG_HIDE_NAVIGATION;
+
     /**
      * Find views that render the specified text.
      *
@@ -13027,6 +13036,8 @@ public void setOnSystemUiVisibilityChangeListener(OnSystemUiVisibilityChangeList
     }
 
     /**
+     * Dispatch callbacks to {@link #setOnSystemUiVisibilityChangeListener} down
+     * the view hierarchy.
      */
     public void dispatchSystemUiVisibilityChanged(int visibility) {
         if (mOnSystemUiVisibilityChangeListener != null) {
@@ -13035,6 +13046,13 @@ public void dispatchSystemUiVisibilityChanged(int visibility) {
         }
     }
 
+    void updateLocalSystemUiVisibility(int localValue, int localChanges) {
+        int val = (mSystemUiVisibility&~localChanges) | (localValue&localChanges);
+        if (val != mSystemUiVisibility) {
+            setSystemUiVisibility(val);
+        }
+    }
+
     /**
      * Creates an image that the system displays during the drag and drop
      * operation. This is called a "drag shadow". The default implementation
@@ -14108,7 +14126,8 @@ public interface OnCreateContextMenuListener {
 
     /**
      * Interface definition for a callback to be invoked when the status bar changes
-     * visibility.
+     * visibility.  This reports <strong>global</strong> changes to the system UI
+     * state, not just what the application is requesting.
      *
      * @see View#setOnSystemUiVisibilityChangeListener(android.view.View.OnSystemUiVisibilityChangeListener) 
      */
@@ -14118,7 +14137,9 @@ public interface OnSystemUiVisibilityChangeListener {
          * {@link View#setSystemUiVisibility(int)}.
          *
          * @param visibility  Bitwise-or of flags {@link #SYSTEM_UI_FLAG_LOW_PROFILE} or
-         * {@link #SYSTEM_UI_FLAG_HIDE_NAVIGATION}.
+         * {@link #SYSTEM_UI_FLAG_HIDE_NAVIGATION}.  This tells you the
+         * <strong>global</strong> state of the UI visibility flags, not what your
+         * app is currently applying.
          */
         public void onSystemUiVisibilityChange(int visibility);
     }
@@ -14375,6 +14396,11 @@ public void setPooled(boolean isPooled) {
          */
         boolean mRecomputeGlobalAttributes;
 
+        /**
+         * Always report new attributes at next traversal.
+         */
+        boolean mForceReportNewAttributes;
+
         /**
          * Set during a traveral if any views want to keep the screen on.
          */

core/java/android/view/ViewGroup.java

@@ -1200,6 +1200,18 @@ public void dispatchSystemUiVisibilityChanged(int visible) {
         }
     }
 
+    @Override
+    void updateLocalSystemUiVisibility(int localValue, int localChanges) {
+        super.updateLocalSystemUiVisibility(localValue, localChanges);
+
+        final int count = mChildrenCount;
+        final View[] children = mChildren;
+        for (int i=0; i <count; i++) {
+            final View child = children[i];
+            child.updateLocalSystemUiVisibility(localValue, localChanges);
+        }
+    }
+
     /**
      * {@inheritDoc}
      */

core/java/android/view/ViewRootImpl.java

@@ -165,6 +165,8 @@ public final class ViewRootImpl extends Handler implements ViewParent,
 
     final int mTargetSdkVersion;
 
+    int mSeq;
+
     View mView;
     View mFocusedView;
     View mRealFocusedView;  // this is not set to null in touch mode
@@ -308,6 +310,13 @@ public static IWindowSession getWindowSession(Looper mainLooper) {
             return sWindowSession;
         }
     }
+
+    static final class SystemUiVisibilityInfo {
+        int seq;
+        int globalVisibility;
+        int localValue;
+        int localChanges;
+    }
 
     public ViewRootImpl(Context context) {
         super();
@@ -465,7 +474,7 @@ public void setView(View view, WindowManager.LayoutParams attrs, View panelParen
                 }
                 try {
                     mOrigWindowType = mWindowAttributes.type;
-                    res = sWindowSession.add(mWindow, mWindowAttributes,
+                    res = sWindowSession.add(mWindow, mSeq, mWindowAttributes,
                             getHostVisibility(), mAttachInfo.mContentInsets,
                             mInputChannel);
                 } catch (RemoteException e) {
@@ -1045,16 +1054,21 @@ private void performTraversals() {
             attachInfo.mRecomputeGlobalAttributes = false;
             boolean oldScreenOn = attachInfo.mKeepScreenOn;
             int oldVis = attachInfo.mSystemUiVisibility;
+            boolean oldHasSystemUiListeners = attachInfo.mHasSystemUiListeners;
             attachInfo.mKeepScreenOn = false;
             attachInfo.mSystemUiVisibility = 0;
             attachInfo.mHasSystemUiListeners = false;
             host.dispatchCollectViewAttributes(0);
             if (attachInfo.mKeepScreenOn != oldScreenOn
                     || attachInfo.mSystemUiVisibility != oldVis
-                    || attachInfo.mHasSystemUiListeners) {
+                    || attachInfo.mHasSystemUiListeners != oldHasSystemUiListeners) {
                 params = lp;
             }
         }
+        if (attachInfo.mForceReportNewAttributes) {
+            attachInfo.mForceReportNewAttributes = false;
+            params = lp;
+        }
 
         if (mFirst || attachInfo.mViewVisibilityChanged) {
             attachInfo.mViewVisibilityChanged = false;
@@ -1136,9 +1150,7 @@ private void performTraversals() {
                         params.flags |= WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON;
                     }
                     params.subtreeSystemUiVisibility = attachInfo.mSystemUiVisibility;
-                    params.hasSystemUiListeners = attachInfo.mHasSystemUiListeners
-                            || params.subtreeSystemUiVisibility != 0
-                            || params.systemUiVisibility != 0;
+                    params.hasSystemUiListeners = attachInfo.mHasSystemUiListeners;
                 }
                 if (DEBUG_LAYOUT) {
                     Log.i(TAG, "host=w:" + host.getMeasuredWidth() + ", h:" +
@@ -2545,7 +2557,7 @@ public void handleMessage(Message msg) {
             handleDragEvent(event);
         } break;
         case DISPATCH_SYSTEM_UI_VISIBILITY: {
-            handleDispatchSystemUiVisibilityChanged(msg.arg1);
+            handleDispatchSystemUiVisibilityChanged((SystemUiVisibilityInfo)msg.obj);
         } break;
         case UPDATE_CONFIGURATION: {
             Configuration config = (Configuration)msg.obj;
@@ -3429,12 +3441,27 @@ private void handleDragEvent(DragEvent event) {
         event.recycle();
     }
 
-    public void handleDispatchSystemUiVisibilityChanged(int visibility) {
+    public void handleDispatchSystemUiVisibilityChanged(SystemUiVisibilityInfo args) {
+        if (mSeq != args.seq) {
+            // The sequence has changed, so we need to update our value and make
+            // sure to do a traversal afterward so the window manager is given our
+            // most recent data.
+            mSeq = args.seq;
+            mAttachInfo.mForceReportNewAttributes = true;
+            scheduleTraversals();            
+        }
         if (mView == null) return;
-        if (mAttachInfo != null) {
-            mAttachInfo.mSystemUiVisibility = visibility;
+        if (args.localChanges != 0) {
+            if (mAttachInfo != null) {
+                mAttachInfo.mSystemUiVisibility =
+                        (mAttachInfo.mSystemUiVisibility&~args.localChanges)
+                        | (args.localValue&args.localChanges);
+            }
+            mView.updateLocalSystemUiVisibility(args.localValue, args.localChanges);
+            mAttachInfo.mRecomputeGlobalAttributes = true;
+            scheduleTraversals();            
         }
-        mView.dispatchSystemUiVisibilityChanged(visibility);
+        mView.dispatchSystemUiVisibilityChanged(args.globalVisibility);
     }
 
     public void getLastTouchPoint(Point outLocation) {
@@ -3493,7 +3520,7 @@ private int relayoutWindow(WindowManager.LayoutParams params, int viewVisibility
             }
         }
         int relayoutResult = sWindowSession.relayout(
-                mWindow, params,
+                mWindow, mSeq, params,
                 (int) (mView.getMeasuredWidth() * appScale + 0.5f),
                 (int) (mView.getMeasuredHeight() * appScale + 0.5f),
                 viewVisibility, insetsPending, mWinFrame,
@@ -3796,8 +3823,14 @@ public void dispatchDragEvent(DragEvent event) {
         sendMessage(msg);
     }
 
-    public void dispatchSystemUiVisibilityChanged(int visibility) {
-        sendMessage(obtainMessage(DISPATCH_SYSTEM_UI_VISIBILITY, visibility, 0));
+    public void dispatchSystemUiVisibilityChanged(int seq, int globalVisibility,
+            int localValue, int localChanges) {
+        SystemUiVisibilityInfo args = new SystemUiVisibilityInfo();
+        args.seq = seq;
+        args.globalVisibility = globalVisibility;
+        args.localValue = localValue;
+        args.localChanges = localChanges;
+        sendMessage(obtainMessage(DISPATCH_SYSTEM_UI_VISIBILITY, args));
     }
 
     /**
@@ -4052,10 +4085,12 @@ public void dispatchDragEvent(DragEvent event) {
             }
         }
 
-        public void dispatchSystemUiVisibilityChanged(int visibility) {
+        public void dispatchSystemUiVisibilityChanged(int seq, int globalVisibility,
+                int localValue, int localChanges) {
             final ViewRootImpl viewAncestor = mViewAncestor.get();
             if (viewAncestor != null) {
-                viewAncestor.dispatchSystemUiVisibilityChanged(visibility);
+                viewAncestor.dispatchSystemUiVisibilityChanged(seq, globalVisibility,
+                        localValue, localChanges);
             }
         }
     }

core/java/android/view/WindowManagerPolicy.java

@@ -236,6 +236,12 @@ public void computeFrameLw(Rect parentFrame, Rect displayFrame,
          */
         public WindowManager.LayoutParams getAttrs();
 
+        /**
+         * Retrieve the current system UI visibility flags associated with
+         * this window.
+         */
+        public int getSystemUiVisibility();
+
         /**
          * Get the layer at which this window's surface will be Z-ordered.
          */

core/java/com/android/internal/view/BaseIWindow.java

@@ -27,6 +27,7 @@
 
 public class BaseIWindow extends IWindow.Stub {
     private IWindowSession mSession;
+    public int mSeq;
 
     public void setSession(IWindowSession session) {
         mSession = session;
@@ -69,7 +70,9 @@ public void dispatchWallpaperOffsets(float x, float y, float xStep, float yStep,
     public void dispatchDragEvent(DragEvent event) {
     }
 
-    public void dispatchSystemUiVisibilityChanged(int visibility) {
+    public void dispatchSystemUiVisibilityChanged(int seq, int globalUi,
+            int localValue, int localChanges) {
+        mSeq = seq;
     }
 
     public void dispatchWallpaperCommand(String action, int x, int y,

policy/src/com/android/internal/policy/impl/PhoneWindowManager.java

@@ -3497,8 +3497,7 @@ private void updateSystemUiVisibility() {
         // If there is no window focused, there will be nobody to handle the events
         // anyway, so just hang on in whatever state we're in until things settle down.
         if (mFocusedWindow != null) {
-            final WindowManager.LayoutParams params = mFocusedWindow.getAttrs();
-            final int visibility = params.systemUiVisibility | params.subtreeSystemUiVisibility;
+            final int visibility = mFocusedWindow.getSystemUiVisibility();
             mHandler.post(new Runnable() {
                     public void run() {
                         if (mStatusBarService == null) {