Use the display's actual state in the view hierarchy.

Previously, the view hierarchy would suppress drawing whenever the
PowerManager.isScreenOn() method returned false.  However, this method
really describes the interactive state of the device rather than the
actual display state.  This is especially a problem when there are
multiple displays but it also breaks drawing while in doze mode.

This change makes the view hierarchy consider the actual state of the
display instead on an individual basis.

Bug: 13133142
Change-Id: I69870b6b14a3504607a30562aa48c3452f777c1f

1 files changed, 46 insertions, 36 deletions

diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index 1848a8f..521cfbf 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -36,6 +36,8 @@ import android.graphics.PorterDuff;
 import android.graphics.Rect;
 import android.graphics.Region;
 import android.graphics.drawable.Drawable;
+import android.hardware.display.DisplayManager;
+import android.hardware.display.DisplayManager.DisplayListener;
 import android.media.AudioManager;
 import android.os.Binder;
 import android.os.Bundle;
@@ -134,6 +136,7 @@ public final class ViewRootImpl implements ViewParent,
     final Context mContext;
     final IWindowSession mWindowSession;
     final Display mDisplay;
+    final DisplayManager mDisplayManager;
     final String mBasePackageName;
 
     final int[] mTmpLocation = new int[2];
@@ -368,9 +371,7 @@ public final class ViewRootImpl implements ViewParent,
         mNoncompatDensity = context.getResources().getDisplayMetrics().noncompatDensityDpi;
         mFallbackEventHandler = PolicyManager.makeNewFallbackEventHandler(context);
         mChoreographer = Choreographer.getInstance();
-
-        PowerManager powerManager = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
-        mAttachInfo.mScreenOn = powerManager.isScreenOn();
+        mDisplayManager = (DisplayManager)context.getSystemService(Context.DISPLAY_SERVICE);
         loadSystemProperties();
     }
 
@@ -425,6 +426,10 @@ public final class ViewRootImpl implements ViewParent,
         synchronized (this) {
             if (mView == null) {
                 mView = view;
+
+                mAttachInfo.mDisplayState = mDisplay.getState();
+                mDisplayManager.registerDisplayListener(mDisplayListener, mHandler);
+
                 mViewLayoutDirectionInitial = mView.getRawLayoutDirection();
                 mFallbackEventHandler.setView(view);
                 mWindowAttributes.copyFrom(attrs);
@@ -794,18 +799,43 @@ public final class ViewRootImpl implements ViewParent,
         scheduleTraversals();
     }
 
-    void handleScreenStateChange(boolean on) {
-        if (on != mAttachInfo.mScreenOn) {
-            mAttachInfo.mScreenOn = on;
-            if (mView != null) {
-                mView.dispatchScreenStateChanged(on ? View.SCREEN_STATE_ON : View.SCREEN_STATE_OFF);
-            }
-            if (on) {
-                mFullRedrawNeeded = true;
-                scheduleTraversals();
+    private final DisplayListener mDisplayListener = new DisplayListener() {
+        @Override
+        public void onDisplayChanged(int displayId) {
+            if (mView != null && mDisplay.getDisplayId() == displayId) {
+                final int oldDisplayState = mAttachInfo.mDisplayState;
+                final int newDisplayState = mDisplay.getState();
+                if (oldDisplayState != newDisplayState) {
+                    mAttachInfo.mDisplayState = newDisplayState;
+                    if (oldDisplayState != Display.STATE_UNKNOWN) {
+                        final int oldScreenState = toViewScreenState(oldDisplayState);
+                        final int newScreenState = toViewScreenState(newDisplayState);
+                        if (oldScreenState != newScreenState) {
+                            mView.dispatchScreenStateChanged(newScreenState);
+                        }
+                        if (oldDisplayState == Display.STATE_OFF) {
+                            // Draw was suppressed so we need to for it to happen here.
+                            mFullRedrawNeeded = true;
+                            scheduleTraversals();
+                        }
+                    }
+                }
             }
         }
-    }
+
+        @Override
+        public void onDisplayRemoved(int displayId) {
+        }
+
+        @Override
+        public void onDisplayAdded(int displayId) {
+        }
+
+        private int toViewScreenState(int displayState) {
+            return displayState == Display.STATE_OFF ?
+                    View.SCREEN_STATE_OFF : View.SCREEN_STATE_ON;
+        }
+    };
 
     @Override
     public void requestFitSystemWindows() {
@@ -2236,7 +2266,7 @@ public final class ViewRootImpl implements ViewParent,
     }
 
     private void performDraw() {
-        if (!mAttachInfo.mScreenOn && !mReportNextDraw) {
+        if (mAttachInfo.mDisplayState == Display.STATE_OFF && !mReportNextDraw) {
             return;
         }
 
@@ -2872,6 +2902,8 @@ public final class ViewRootImpl implements ViewParent,
             mInputChannel = null;
         }
 
+        mDisplayManager.unregisterDisplayListener(mDisplayListener);
+
         unscheduleTraversals();
     }
 
@@ -2951,7 +2983,6 @@ public final class ViewRootImpl implements ViewParent,
     private final static int MSG_DISPATCH_SYSTEM_UI_VISIBILITY = 17;
     private final static int MSG_UPDATE_CONFIGURATION = 18;
     private final static int MSG_PROCESS_INPUT_EVENTS = 19;
-    private final static int MSG_DISPATCH_SCREEN_STATE = 20;
     private final static int MSG_CLEAR_ACCESSIBILITY_FOCUS_HOST = 21;
     private final static int MSG_DISPATCH_DONE_ANIMATING = 22;
     private final static int MSG_INVALIDATE_WORLD = 23;
@@ -2998,8 +3029,6 @@ public final class ViewRootImpl implements ViewParent,
                     return "MSG_UPDATE_CONFIGURATION";
                 case MSG_PROCESS_INPUT_EVENTS:
                     return "MSG_PROCESS_INPUT_EVENTS";
-                case MSG_DISPATCH_SCREEN_STATE:
-                    return "MSG_DISPATCH_SCREEN_STATE";
                 case MSG_CLEAR_ACCESSIBILITY_FOCUS_HOST:
                     return "MSG_CLEAR_ACCESSIBILITY_FOCUS_HOST";
                 case MSG_DISPATCH_DONE_ANIMATING:
@@ -3215,11 +3244,6 @@ public final class ViewRootImpl implements ViewParent,
                 }
                 updateConfiguration(config, false);
             } break;
-            case MSG_DISPATCH_SCREEN_STATE: {
-                if (mView != null) {
-                    handleScreenStateChange(msg.arg1 == 1);
-                }
-            } break;
             case MSG_CLEAR_ACCESSIBILITY_FOCUS_HOST: {
                 setAccessibilityFocus(null, null);
             } break;
@@ -5805,12 +5829,6 @@ public final class ViewRootImpl implements ViewParent,
         mHandler.sendMessage(msg);
     }
 
-    public void dispatchScreenStateChange(boolean on) {
-        Message msg = mHandler.obtainMessage(MSG_DISPATCH_SCREEN_STATE);
-        msg.arg1 = on ? 1 : 0;
-        mHandler.sendMessage(msg);
-    }
-
     public void dispatchGetNewSurface() {
         Message msg = mHandler.obtainMessage(MSG_DISPATCH_GET_NEW_SURFACE);
         mHandler.sendMessage(msg);
@@ -6149,14 +6167,6 @@ public final class ViewRootImpl implements ViewParent,
         }
 
         @Override
-        public void dispatchScreenState(boolean on) {
-            final ViewRootImpl viewAncestor = mViewAncestor.get();
-            if (viewAncestor != null) {
-                viewAncestor.dispatchScreenStateChange(on);
-            }
-        }
-
-        @Override
         public void dispatchGetNewSurface() {
             final ViewRootImpl viewAncestor = mViewAncestor.get();
             if (viewAncestor != null) {