Merge "Support nav button color transitions"

core/java/android/inputmethodservice/NavigationBarController.java

@@ -19,6 +19,7 @@ package android.inputmethodservice;
 import static android.content.Intent.ACTION_OVERLAY_CHANGED;
 import static android.view.WindowInsetsController.APPEARANCE_LIGHT_NAVIGATION_BARS;
 
+import android.animation.ValueAnimator;
 import android.annotation.FloatRange;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
@@ -44,6 +45,8 @@ import android.view.Window;
 import android.view.WindowInsets;
 import android.view.WindowInsetsController.Appearance;
 import android.view.WindowManagerPolicyConstants;
+import android.view.animation.Interpolator;
+import android.view.animation.PathInterpolator;
 import android.widget.FrameLayout;
 
 import java.util.Objects;
@@ -115,6 +118,12 @@ final class NavigationBarController {
     }
 
     private static final class Impl implements Callback {
+        private static final int DEFAULT_COLOR_ADAPT_TRANSITION_TIME = 1700;
+
+        // Copied from com.android.systemui.animation.Interpolators#LEGACY_DECELERATE
+        private static final Interpolator LEGACY_DECELERATE =
+                new PathInterpolator(0f, 0f, 0.2f, 1f);
+
         @NonNull
         private final InputMethodService mService;
 
@@ -133,6 +142,12 @@ final class NavigationBarController {
         @Appearance
         private int mAppearance;
 
+        @FloatRange(from = 0.0f, to = 1.0f)
+        private float mDarkIntensity;
+
+        @Nullable
+        private ValueAnimator mTintAnimator;
+
         Impl(@NonNull InputMethodService inputMethodService) {
             mService = inputMethodService;
         }
@@ -368,6 +383,10 @@ final class NavigationBarController {
             if (mDestroyed) {
                 return;
             }
+            if (mTintAnimator != null) {
+                mTintAnimator.cancel();
+                mTintAnimator = null;
+            }
             if (mSystemOverlayChangedReceiver != null) {
                 mService.unregisterReceiver(mSystemOverlayChangedReceiver);
                 mSystemOverlayChangedReceiver = null;
@@ -416,10 +435,24 @@ final class NavigationBarController {
             }
 
             final float targetDarkIntensity = calculateTargetDarkIntensity(mAppearance);
-            setIconTintInternal(targetDarkIntensity);
+
+            if (mTintAnimator != null) {
+                mTintAnimator.cancel();
+            }
+            mTintAnimator = ValueAnimator.ofFloat(mDarkIntensity, targetDarkIntensity);
+            mTintAnimator.addUpdateListener(
+                    animation -> setIconTintInternal((Float) animation.getAnimatedValue()));
+            mTintAnimator.setDuration(DEFAULT_COLOR_ADAPT_TRANSITION_TIME);
+            mTintAnimator.setStartDelay(0);
+            mTintAnimator.setInterpolator(LEGACY_DECELERATE);
+            mTintAnimator.start();
         }
 
         private void setIconTintInternal(float darkIntensity) {
+            mDarkIntensity = darkIntensity;
+            if (mNavigationBarFrame == null) {
+                return;
+            }
             final NavigationBarView navigationBarView =
                     mNavigationBarFrame.findViewByPredicate(NavigationBarView.class::isInstance);
             if (navigationBarView == null) {
@@ -439,6 +472,7 @@ final class NavigationBarController {
             return "{mRenderGesturalNavButtons=" + mRenderGesturalNavButtons
                     + " mNavigationBarFrame=" + mNavigationBarFrame
                     + " mAppearance=0x" + Integer.toHexString(mAppearance)
+                    + " mDarkIntensity=" + mDarkIntensity
                     + "}";
         }
     }