1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License
15  */
16 
17 package com.android.systemui.statusbar;
18 
19 import android.animation.Animator;
20 import android.animation.AnimatorListenerAdapter;
21 import android.animation.ValueAnimator;
22 import android.content.Context;
23 import android.graphics.Canvas;
24 import android.graphics.Color;
25 import android.graphics.PorterDuff;
26 import android.util.AttributeSet;
27 import android.view.View;
28 import android.view.animation.Interpolator;
29 
30 /**
31  * A view which can draw a scrim
32  */
33 public class ScrimView extends View
34 {
35     private int mScrimColor;
36     private boolean mIsEmpty = true;
37     private boolean mDrawAsSrc;
38     private float mViewAlpha = 1.0f;
39     private ValueAnimator mAlphaAnimator;
40     private ValueAnimator.AnimatorUpdateListener mAlphaUpdateListener
41             = new ValueAnimator.AnimatorUpdateListener() {
42         @Override
43         public void onAnimationUpdate(ValueAnimator animation) {
44             mViewAlpha = (float) animation.getAnimatedValue();
45             invalidate();
46         }
47     };
48     private AnimatorListenerAdapter mClearAnimatorListener = new AnimatorListenerAdapter() {
49         @Override
50         public void onAnimationEnd(Animator animation) {
51             mAlphaAnimator = null;
52         }
53     };
54 
ScrimView(Context context)55     public ScrimView(Context context) {
56         this(context, null);
57     }
58 
ScrimView(Context context, AttributeSet attrs)59     public ScrimView(Context context, AttributeSet attrs) {
60         this(context, attrs, 0);
61     }
62 
ScrimView(Context context, AttributeSet attrs, int defStyleAttr)63     public ScrimView(Context context, AttributeSet attrs, int defStyleAttr) {
64         this(context, attrs, defStyleAttr, 0);
65     }
66 
ScrimView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)67     public ScrimView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
68         super(context, attrs, defStyleAttr, defStyleRes);
69     }
70 
71     @Override
onDraw(Canvas canvas)72     protected void onDraw(Canvas canvas) {
73         if (mDrawAsSrc || (!mIsEmpty && mViewAlpha > 0f)) {
74             PorterDuff.Mode mode = mDrawAsSrc ? PorterDuff.Mode.SRC : PorterDuff.Mode.SRC_OVER;
75             int color = mScrimColor;
76             color = Color.argb((int) (Color.alpha(color) * mViewAlpha), Color.red(color),
77                     Color.green(color), Color.blue(color));
78             canvas.drawColor(color, mode);
79         }
80     }
81 
setDrawAsSrc(boolean asSrc)82     public void setDrawAsSrc(boolean asSrc) {
83         mDrawAsSrc = asSrc;
84         invalidate();
85     }
86 
setScrimColor(int color)87     public void setScrimColor(int color) {
88         if (color != mScrimColor) {
89             mIsEmpty = Color.alpha(color) == 0;
90             mScrimColor = color;
91             invalidate();
92         }
93     }
94 
getScrimColor()95     public int getScrimColor() {
96         return mScrimColor;
97     }
98 
99     @Override
hasOverlappingRendering()100     public boolean hasOverlappingRendering() {
101         return false;
102     }
103 
setViewAlpha(float alpha)104     public void setViewAlpha(float alpha) {
105         if (mAlphaAnimator != null) {
106             mAlphaAnimator.cancel();
107         }
108         mViewAlpha = alpha;
109         invalidate();
110     }
111 
animateViewAlpha(float alpha, long durationOut, Interpolator interpolator)112     public void animateViewAlpha(float alpha, long durationOut, Interpolator interpolator) {
113         if (mAlphaAnimator != null) {
114             mAlphaAnimator.cancel();
115         }
116         mAlphaAnimator = ValueAnimator.ofFloat(mViewAlpha, alpha);
117         mAlphaAnimator.addUpdateListener(mAlphaUpdateListener);
118         mAlphaAnimator.addListener(mClearAnimatorListener);
119         mAlphaAnimator.setInterpolator(interpolator);
120         mAlphaAnimator.setDuration(durationOut);
121         mAlphaAnimator.start();
122     }
123 }
124