Fade in background scrim when resuming from screen off.

This change hides the hard cut off that appears when the Launcher
window is transitioning upwards when resuming from when the screen
is off.

Bug: 36446766

Change-Id: I0c0fe13ee9e08d27b94916d0407ef431d82b8d6a

src/com/android/launcher3/Launcher.java

@@ -18,7 +18,9 @@ package com.android.launcher3;
 
 import android.Manifest;
 import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
 import android.animation.AnimatorSet;
+import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
@@ -267,6 +269,8 @@ public class Launcher extends BaseActivity
     private boolean mHasFocus = false;
     private boolean mAttached = false;
 
+    private ObjectAnimator mScrimAnimator;
+
     private PopupDataProvider mPopupDataProvider;
 
     private View.OnTouchListener mHapticFeedbackTouchListener;
@@ -920,6 +924,24 @@ public class Launcher extends BaseActivity
         if (!isWorkspaceLoading()) {
             NotificationListener.setNotificationsChangedListener(mPopupDataProvider);
         }
+
+        if (mIsResumeFromActionScreenOff && mDragLayer.getBackground() != null) {
+            if (mScrimAnimator != null) {
+                mScrimAnimator.cancel();
+            }
+            mDragLayer.getBackground().setAlpha(0);
+            mScrimAnimator = ObjectAnimator.ofInt(mDragLayer.getBackground(),
+                    LauncherAnimUtils.DRAWABLE_ALPHA, 0, 255);
+            mScrimAnimator.addListener(new AnimatorListenerAdapter() {
+                @Override
+                public void onAnimationEnd(Animator animation) {
+                    mScrimAnimator = null;
+                }
+            });
+            mScrimAnimator.setDuration(600);
+            mScrimAnimator.setStartDelay(getWindow().getTransitionBackgroundFadeDuration());
+            mScrimAnimator.start();
+        }
     }
 
     @Override

src/com/android/launcher3/LauncherAnimUtils.java

@@ -21,6 +21,7 @@ import android.animation.AnimatorSet;
 import android.animation.ObjectAnimator;
 import android.animation.PropertyValuesHolder;
 import android.animation.ValueAnimator;
+import android.graphics.drawable.Drawable;
 import android.util.Property;
 import android.view.View;
 import android.view.ViewTreeObserver;
@@ -128,4 +129,16 @@ public class LauncherAnimUtils {
         return anim;
     }
 
+    public static final Property<Drawable, Integer> DRAWABLE_ALPHA =
+            new Property<Drawable, Integer>(Integer.TYPE, "drawableAlpha") {
+                @Override
+                public Integer get(Drawable drawable) {
+                    return drawable.getAlpha();
+                }
+
+                @Override
+                public void set(Drawable drawable, Integer alpha) {
+                    drawable.setAlpha(alpha);
+                }
+            };
 }

src/com/android/launcher3/allapps/AllAppsBackgroundDrawable.java

@@ -25,6 +25,7 @@ import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.view.Gravity;
 
+import com.android.launcher3.LauncherAnimUtils;
 import com.android.launcher3.R;
 
 /**
@@ -119,7 +120,8 @@ public class AllAppsBackgroundDrawable extends Drawable {
         int finalAlphaI = (int) (finalAlpha * 255f);
         if (getAlpha() != finalAlphaI) {
             mBackgroundAnim = cancelAnimator(mBackgroundAnim);
-            mBackgroundAnim = ObjectAnimator.ofInt(this, "alpha", finalAlphaI);
+            mBackgroundAnim = ObjectAnimator.ofInt(this, LauncherAnimUtils.DRAWABLE_ALPHA,
+                    finalAlphaI);
             mBackgroundAnim.setDuration(duration);
             mBackgroundAnim.start();
         }