commit acfac6187dd9d13d55b566a77a5da867a1813573
author Alex Chau <alexchau@google.com> Mon Oct 19 18:00:39 2020 +0100
committer Alex Chau <alexchau@google.com> Tue Oct 20 20:19:57 2020 +0100
tree 7ecb76d30f948159da1089f78ae12d7d136cbc48
parent b03d2b41616d479ba360fa4f97e57722c7f57b8e

Use Diplay.getMetrics in DisplayController

- This is a workaround of b/163815566, where DisplayMetrics is stale
  when onDisplayChanged is called.
- Instead of relying on stale DisplayConext, get the DisplayMetrics
  from the Display directly.
- Also optimized how DisplayController.Info is created by passing in
  Display only
- Use mDisplayContext.getDisplay directly if availalbe

Bug: 163815566, 160544577
Test: DPI looks correct on device boot
Change-Id: I2a7454bb8cf2073ce592e8662781b87fc998444f
(cherry picked from commit 177c38243dc3bf245d1f7db3c265dfb56522f441)

src/com/android/launcher3/InvariantDeviceProfile.java

diff --git a/src/com/android/launcher3/InvariantDeviceProfile.java b/src/com/android/launcher3/InvariantDeviceProfile.java
index 370bd6f..ff53b5f 100644
--- a/src/com/android/launcher3/InvariantDeviceProfile.java
+++ b/src/com/android/launcher3/InvariantDeviceProfile.java
@@ -201,7 +201,7 @@
                 DisplayController.getDefaultDisplay(context).getInfo(),
                 getPredefinedDeviceProfiles(context, gridName));
 
-        Info myInfo = new Info(context, display);
+        Info myInfo = new Info(display);
         DisplayOption myDisplayOption = invDistWeightedInterpolate(
                 myInfo, getPredefinedDeviceProfiles(context, gridName));
 

src/com/android/launcher3/util/DisplayController.java

diff --git a/src/com/android/launcher3/util/DisplayController.java b/src/com/android/launcher3/util/DisplayController.java
index 355c949..3ab736a 100644
--- a/src/com/android/launcher3/util/DisplayController.java
+++ b/src/com/android/launcher3/util/DisplayController.java
@@ -31,6 +31,8 @@
 
 import androidx.annotation.VisibleForTesting;
 
+import com.android.launcher3.Utilities;
+
 import java.util.ArrayList;
 
 /**
@@ -157,13 +159,13 @@
         private final ArrayList<DisplayInfoChangeListener> mListeners = new ArrayList<>();
         private DisplayController.Info mInfo;
 
-        private DisplayHolder(Context displayContext) {
+        private DisplayHolder(Context displayContext, Display display) {
             mDisplayContext = displayContext;
             // Note that the Display object must be obtained from DisplayManager which is
             // associated to the display context, so the Display is isolated from Activity and
             // Application to provide the actual state of device that excludes the additional
             // adjustment and override.
-            mInfo = new DisplayController.Info(mDisplayContext);
+            mInfo = new DisplayController.Info(display);
             mId = mInfo.id;
         }
 
@@ -180,22 +182,31 @@
         }
 
         protected void handleOnChange() {
+            Display display = Utilities.ATLEAST_R
+                    ? mDisplayContext.getDisplay()
+                    : mDisplayContext
+                        .getSystemService(DisplayManager.class)
+                        .getDisplay(mId);
+            if (display == null) {
+                return;
+            }
+
             Info oldInfo = mInfo;
-            Info info = new Info(mDisplayContext);
+            Info newInfo = new Info(display);
 
             int change = 0;
-            if (info.hasDifferentSize(oldInfo)) {
+            if (newInfo.hasDifferentSize(oldInfo)) {
                 change |= CHANGE_SIZE;
             }
-            if (oldInfo.rotation != info.rotation) {
+            if (newInfo.rotation != oldInfo.rotation) {
                 change |= CHANGE_ROTATION;
             }
-            if (info.singleFrameMs != oldInfo.singleFrameMs) {
+            if (newInfo.singleFrameMs != oldInfo.singleFrameMs) {
                 change |= CHANGE_FRAME_DELAY;
             }
 
             if (change != 0) {
-                mInfo = info;
+                mInfo = newInfo;
                 final int flags = change;
                 MAIN_EXECUTOR.execute(() -> notifyChange(flags));
             }
@@ -216,7 +227,7 @@
             // Use application context to create display context so that it can have its own
             // Resources.
             Context displayContext = context.getApplicationContext().createDisplayContext(display);
-            return new DisplayHolder(displayContext);
+            return new DisplayHolder(displayContext, display);
         }
     }
 
@@ -244,12 +255,7 @@
             this.metrics = metrics;
         }
 
-        private Info(Context context) {
-            this(context, context.getSystemService(DisplayManager.class)
-                    .getDisplay(DEFAULT_DISPLAY));
-        }
-
-        public Info(Context context, Display display) {
+        public Info(Display display) {
             id = display.getDisplayId();
             rotation = display.getRotation();
 
@@ -262,7 +268,8 @@
             display.getRealSize(realSize);
             display.getCurrentSizeRange(smallestSize, largestSize);
 
-            metrics = context.getResources().getDisplayMetrics();
+            metrics = new DisplayMetrics();
+            display.getMetrics(metrics);
         }
 
         private boolean hasDifferentSize(Info info) {