ScrimState.java

 /*
  * Copyright (C) 2017 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License
  */

 package com.android.systemui.statusbar.phone;

 import android.graphics.Color;
 import android.os.Trace;
 import android.util.MathUtils;

 import com.android.keyguard.KeyguardUpdateMonitor;
 import com.android.systemui.statusbar.ScrimView;
 import com.android.systemui.statusbar.stack.StackStateAnimator;

 /**
  * Possible states of the ScrimController state machine.
  */
 public enum ScrimState {

     /**
      * Initial state.
      */
     UNINITIALIZED(-1),

     /**
      * On the lock screen.
      */
     KEYGUARD(0) {

         @Override
         public void prepare(ScrimState previousState) {
             mBlankScreen = false;
             if (previousState == ScrimState.AOD) {
                 mAnimationDuration = StackStateAnimator.ANIMATION_DURATION_WAKEUP;
                 if (mDisplayRequiresBlanking) {
                     // DisplayPowerManager will blank the screen, we'll just
                     // set our scrim to black in this frame to avoid flickering and
                     // fade it out afterwards.
                     mBlankScreen = true;
                 }
             } else {
                 mAnimationDuration = ScrimController.ANIMATION_DURATION;
             }
             mCurrentBehindAlpha = mScrimBehindAlphaKeyguard;
             mCurrentInFrontAlpha = 0;
         }

         @Override
         public float getBehindAlpha(float busynessFactor) {
             return MathUtils.map(0 /* start */, 1 /* stop */,
                    mScrimBehindAlphaKeyguard, ScrimController.GRADIENT_SCRIM_ALPHA_BUSY,
                    busynessFactor);
         }
     },

     /**
      * Showing password challenge on the keyguard.
      */
     BOUNCER(1) {
         @Override
         public void prepare(ScrimState previousState) {
             mCurrentBehindAlpha = ScrimController.GRADIENT_SCRIM_ALPHA_BUSY;
             mCurrentInFrontAlpha = 0f;
         }
     },

     /**
      * Showing password challenge on top of a FLAG_SHOW_WHEN_LOCKED activity.
      */
     BOUNCER_SCRIMMED(2) {
         @Override
         public void prepare(ScrimState previousState) {
             mCurrentBehindAlpha = 0;
             mCurrentInFrontAlpha = ScrimController.GRADIENT_SCRIM_ALPHA_BUSY;
         }
     },

     /**
      * Changing screen brightness from quick settings.
      */
     BRIGHTNESS_MIRROR(3) {
         @Override
         public void prepare(ScrimState previousState) {
             mCurrentBehindAlpha = 0;
             mCurrentInFrontAlpha = 0;
         }
     },

     /**
      * Always on display or screen off.
      */
     AOD(4) {
         @Override
         public void prepare(ScrimState previousState) {
             final boolean alwaysOnEnabled = mDozeParameters.getAlwaysOn();
             mBlankScreen = mDisplayRequiresBlanking;
             mCurrentBehindAlpha = mWallpaperSupportsAmbientMode
                     && !mKeyguardUpdateMonitor.hasLockscreenWallpaper() ? 0f : 1f;
             mCurrentInFrontAlpha = alwaysOnEnabled ? mAodFrontScrimAlpha : 1f;
             mCurrentInFrontTint = Color.BLACK;
             mCurrentBehindTint = Color.BLACK;
             mAnimationDuration = ScrimController.ANIMATION_DURATION_LONG;
             // DisplayPowerManager may blank the screen for us,
             // in this case we just need to set our state.
             mAnimateChange = mDozeParameters.shouldControlScreenOff();
         }

         @Override
         public boolean isLowPowerState() {
             return true;
         }
     },

     /**
      * When phone wakes up because you received a notification.
      */
     PULSING(5) {
         @Override
         public void prepare(ScrimState previousState) {
             mCurrentInFrontAlpha = 0;
             mCurrentInFrontTint = Color.BLACK;
             mCurrentBehindAlpha = mWallpaperSupportsAmbientMode
                     && !mKeyguardUpdateMonitor.hasLockscreenWallpaper() ? 0f : 1f;
             mCurrentBehindTint = Color.BLACK;
             mBlankScreen = mDisplayRequiresBlanking;
         }
     },

     /**
      * Unlocked on top of an app (launcher or any other activity.)
      */
     UNLOCKED(6) {
         @Override
         public void prepare(ScrimState previousState) {
             mCurrentBehindAlpha = 0;
             mCurrentInFrontAlpha = 0;
             mAnimationDuration = StatusBar.FADE_KEYGUARD_DURATION;

             if (previousState == ScrimState.AOD || previousState == ScrimState.PULSING) {
                 // Fade from black to transparent when coming directly from AOD
                 updateScrimColor(mScrimInFront, 1, Color.BLACK);
                 updateScrimColor(mScrimBehind, 1, Color.BLACK);
                 // Scrims should still be black at the end of the transition.
                 mCurrentInFrontTint = Color.BLACK;
                 mCurrentBehindTint = Color.BLACK;
                 mBlankScreen = true;
             } else {
                 mCurrentInFrontTint = Color.TRANSPARENT;
                 mCurrentBehindTint = Color.TRANSPARENT;
                 mBlankScreen = false;
             }
         }
     };

     boolean mBlankScreen = false;
     long mAnimationDuration = ScrimController.ANIMATION_DURATION;
     int mCurrentInFrontTint = Color.TRANSPARENT;
     int mCurrentBehindTint = Color.TRANSPARENT;
     boolean mAnimateChange = true;
     float mCurrentInFrontAlpha;
     float mCurrentBehindAlpha;
     float mAodFrontScrimAlpha;
     float mScrimBehindAlphaKeyguard;
     ScrimView mScrimInFront;
     ScrimView mScrimBehind;
     DozeParameters mDozeParameters;
     boolean mDisplayRequiresBlanking;
     boolean mWallpaperSupportsAmbientMode;
     KeyguardUpdateMonitor mKeyguardUpdateMonitor;
     int mIndex;

     ScrimState(int index) {
         mIndex = index;
     }

     public void init(ScrimView scrimInFront, ScrimView scrimBehind, DozeParameters dozeParameters) {
         mScrimInFront = scrimInFront;
         mScrimBehind = scrimBehind;
         mDozeParameters = dozeParameters;
         mDisplayRequiresBlanking = dozeParameters.getDisplayNeedsBlanking();
         mKeyguardUpdateMonitor = KeyguardUpdateMonitor.getInstance(scrimInFront.getContext());
     }

     public void prepare(ScrimState previousState) {
     }

     public int getIndex() {
         return mIndex;
     }

     public float getFrontAlpha() {
         return mCurrentInFrontAlpha;
     }

     public float getBehindAlpha(float busyness) {
         return mCurrentBehindAlpha;
     }

     public int getFrontTint() {
         return mCurrentInFrontTint;
     }

     public int getBehindTint() {
         return mCurrentBehindTint;
     }

     public long getAnimationDuration() {
         return mAnimationDuration;
     }

     public boolean getBlanksScreen() {
         return mBlankScreen;
     }

     public void updateScrimColor(ScrimView scrim, float alpha, int tint) {
         Trace.traceCounter(Trace.TRACE_TAG_APP,
                 scrim == mScrimInFront ? "front_scrim_alpha" : "back_scrim_alpha",
                 (int) (alpha * 255));

         Trace.traceCounter(Trace.TRACE_TAG_APP,
                 scrim == mScrimInFront ? "front_scrim_tint" : "back_scrim_tint",
                 Color.alpha(tint));

         scrim.setTint(tint);
         scrim.setViewAlpha(alpha);
     }

     public boolean getAnimateChange() {
         return mAnimateChange;
     }

     public void setAodFrontScrimAlpha(float aodFrontScrimAlpha) {
         mAodFrontScrimAlpha = aodFrontScrimAlpha;
     }

     public void setScrimBehindAlphaKeyguard(float scrimBehindAlphaKeyguard) {
         mScrimBehindAlphaKeyguard = scrimBehindAlphaKeyguard;
     }

     public void setWallpaperSupportsAmbientMode(boolean wallpaperSupportsAmbientMode) {
         mWallpaperSupportsAmbientMode = wallpaperSupportsAmbientMode;
     }

     public boolean isLowPowerState() {
         return false;
     }
 }