Improve the performance when loading image wallpaper colors

When SystemUI start up, ColorExtractor will get wallpaper colors so
status bar can use it to update theme, however, this will also block
SystemUI start up process if the wallpaper is image wallpaper.
In order to break the latency, we can extract getWallpaperColors
method from ColorExtractor's contructor, and do it at another thread,
so it won't block SystemUI start up.

Bug: 124279857
Test: atest ColorExtractorTest
Test: Manual test change theme feature can work normally.

Change-Id: I8589b28a17b0a2b33b4bbbda2265080af983f26a

3 files changed, 38 insertions, 13 deletions

diff --git a/core/java/com/android/internal/colorextraction/ColorExtractor.java b/core/java/com/android/internal/colorextraction/ColorExtractor.java
index 258d081c6ad8..d9fd3b5bd6d8 100644
--- a/core/java/com/android/internal/colorextraction/ColorExtractor.java
+++ b/core/java/com/android/internal/colorextraction/ColorExtractor.java
@@ -21,7 +21,7 @@ import android.annotation.Nullable;
 import android.app.WallpaperColors;
 import android.app.WallpaperManager;
 import android.content.Context;
-import android.os.Trace;
+import android.os.AsyncTask;
 import android.util.Log;
 import android.util.SparseArray;
 
@@ -53,11 +53,11 @@ public class ColorExtractor implements WallpaperManager.OnColorsChangedListener
     protected WallpaperColors mLockColors;
 
     public ColorExtractor(Context context) {
-        this(context, new Tonal(context));
+        this(context, new Tonal(context), true /* immediately */);
     }
 
     @VisibleForTesting
-    public ColorExtractor(Context context, ExtractionType extractionType) {
+    public ColorExtractor(Context context, ExtractionType extractionType, boolean immediately) {
         mContext = context;
         mExtractionType = extractionType;
 
@@ -71,23 +71,48 @@ public class ColorExtractor implements WallpaperManager.OnColorsChangedListener
         }
 
         mOnColorsChangedListeners = new ArrayList<>();
-        GradientColors[] systemColors = mGradientColors.get(WallpaperManager.FLAG_SYSTEM);
-        GradientColors[] lockColors = mGradientColors.get(WallpaperManager.FLAG_LOCK);
 
         WallpaperManager wallpaperManager = mContext.getSystemService(WallpaperManager.class);
         if (wallpaperManager == null) {
             Log.w(TAG, "Can't listen to color changes!");
         } else {
             wallpaperManager.addOnColorsChangedListener(this, null /* handler */);
+            initExtractColors(wallpaperManager, immediately);
+        }
+    }
 
-            // Initialize all gradients with the current colors
-            Trace.beginSection("ColorExtractor#getWallpaperColors");
+    private void initExtractColors(WallpaperManager wallpaperManager, boolean immediately) {
+        if (immediately) {
             mSystemColors = wallpaperManager.getWallpaperColors(WallpaperManager.FLAG_SYSTEM);
             mLockColors = wallpaperManager.getWallpaperColors(WallpaperManager.FLAG_LOCK);
-            Trace.endSection();
+            extractWallpaperColors();
+        } else {
+            new LoadWallpaperColors().executeOnExecutor(
+                    AsyncTask.THREAD_POOL_EXECUTOR, wallpaperManager);
+        }
+    }
+
+    private class LoadWallpaperColors extends AsyncTask<WallpaperManager, Void, Void> {
+        private WallpaperColors mSystemColors;
+        private WallpaperColors mLockColors;
+        @Override
+        protected Void doInBackground(WallpaperManager... params) {
+            mSystemColors = params[0].getWallpaperColors(WallpaperManager.FLAG_SYSTEM);
+            mLockColors = params[0].getWallpaperColors(WallpaperManager.FLAG_LOCK);
+            return null;
+        }
+        @Override
+        protected void onPostExecute(Void b) {
+            ColorExtractor.this.mSystemColors = mSystemColors;
+            ColorExtractor.this.mLockColors = mLockColors;
+            extractWallpaperColors();
+            triggerColorsChanged(WallpaperManager.FLAG_SYSTEM | WallpaperManager.FLAG_LOCK);
         }
+    }
 
-        // Initialize all gradients with the current colors
+    private void extractWallpaperColors() {
+        GradientColors[] systemColors = mGradientColors.get(WallpaperManager.FLAG_SYSTEM);
+        GradientColors[] lockColors = mGradientColors.get(WallpaperManager.FLAG_LOCK);
         extractInto(mSystemColors,
                 systemColors[TYPE_NORMAL],
                 systemColors[TYPE_DARK],
diff --git a/packages/SystemUI/src/com/android/systemui/colorextraction/SysuiColorExtractor.java b/packages/SystemUI/src/com/android/systemui/colorextraction/SysuiColorExtractor.java
index 900ea72d856c..a74c3287e1f1 100644
--- a/packages/SystemUI/src/com/android/systemui/colorextraction/SysuiColorExtractor.java
+++ b/packages/SystemUI/src/com/android/systemui/colorextraction/SysuiColorExtractor.java
@@ -61,7 +61,7 @@ public class SysuiColorExtractor extends ColorExtractor implements Dumpable {
 
     @VisibleForTesting
     public SysuiColorExtractor(Context context, ExtractionType type, boolean registerVisibility) {
-        super(context, type);
+        super(context, type, false /* immediately */);
         mTonal = type instanceof Tonal ? (Tonal) type : new Tonal(context);
         mWpHiddenColors = new GradientColors();
 
diff --git a/tests/Internal/src/com/android/internal/colorextraction/ColorExtractorTest.java b/tests/Internal/src/com/android/internal/colorextraction/ColorExtractorTest.java
index cb6a83d2644b..39608a40b416 100644
--- a/tests/Internal/src/com/android/internal/colorextraction/ColorExtractorTest.java
+++ b/tests/Internal/src/com/android/internal/colorextraction/ColorExtractorTest.java
@@ -56,7 +56,7 @@ public class ColorExtractorTest {
     @Test
     public void ColorExtractor_extractWhenInitialized() {
         ExtractionType type = mock(Tonal.class);
-        new ColorExtractor(mContext, type);
+        new ColorExtractor(mContext, type, true);
         // 1 for lock and 1 for system
         verify(type, times(2))
                 .extractInto(any(), any(), any(), any());
@@ -83,7 +83,7 @@ public class ColorExtractorTest {
                     outGradientColorsDark.set(colorsExpectedDark);
                     outGradientColorsExtraDark.set(colorsExpectedExtraDark);
                 };
-        ColorExtractor extractor = new ColorExtractor(mContext, type);
+        ColorExtractor extractor = new ColorExtractor(mContext, type, true);
 
         GradientColors colors = extractor.getColors(WallpaperManager.FLAG_SYSTEM,
                 ColorExtractor.TYPE_NORMAL);
@@ -98,7 +98,7 @@ public class ColorExtractorTest {
     public void addOnColorsChangedListener_invokesListener() {
         ColorExtractor.OnColorsChangedListener mockedListeners =
                 mock(ColorExtractor.OnColorsChangedListener.class);
-        ColorExtractor extractor = new ColorExtractor(mContext, new Tonal(mContext));
+        ColorExtractor extractor = new ColorExtractor(mContext, new Tonal(mContext), true);
         extractor.addOnColorsChangedListener(mockedListeners);
 
         extractor.onColorsChanged(new WallpaperColors(Color.valueOf(Color.RED), null, null),