ViewInvertHelper.java revision c18010f6720f606003cde3cd376ddacaca30f6e5 
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
17package com.android.systemui;
18
19import android.animation.Animator;
20import android.animation.AnimatorListenerAdapter;
21import android.animation.ValueAnimator;
22import android.content.Context;
23import android.graphics.ColorMatrix;
24import android.graphics.ColorMatrixColorFilter;
25import android.graphics.Paint;
26import android.view.View;
27
28import com.android.systemui.statusbar.Interpolators;
29
30import java.util.ArrayList;
31
32/**
33 * Helper to invert the colors of views and fade between the states.
34 */
35public class ViewInvertHelper {
36
37    private final Paint mDarkPaint = new Paint();
38    private final ColorMatrix mMatrix = new ColorMatrix();
39    private final ColorMatrix mGrayscaleMatrix = new ColorMatrix();
40    private final long mFadeDuration;
41    private final ArrayList<View> mTargets = new ArrayList<>();
42
43    public ViewInvertHelper(View v, long fadeDuration) {
44        this(v.getContext(), fadeDuration);
45        addTarget(v);
46    }
47    public ViewInvertHelper(Context context, long fadeDuration) {
48        mFadeDuration = fadeDuration;
49    }
50
51    private static ArrayList<View> constructArray(View target) {
52        final ArrayList<View> views = new ArrayList<>();
53        views.add(target);
54        return views;
55    }
56
57    public void clearTargets() {
58        mTargets.clear();
59    }
60
61    public void addTarget(View target) {
62        mTargets.add(target);
63    }
64
65    public void fade(final boolean invert, long delay) {
66        float startIntensity = invert ? 0f : 1f;
67        float endIntensity = invert ? 1f : 0f;
68        ValueAnimator animator = ValueAnimator.ofFloat(startIntensity, endIntensity);
69        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
70            @Override
71            public void onAnimationUpdate(ValueAnimator animation) {
72                updateInvertPaint((Float) animation.getAnimatedValue());
73                for (int i = 0; i < mTargets.size(); i++) {
74                    mTargets.get(i).setLayerType(View.LAYER_TYPE_HARDWARE, mDarkPaint);
75                }
76            }
77        });
78        animator.addListener(new AnimatorListenerAdapter() {
79            @Override
80            public void onAnimationEnd(Animator animation) {
81                if (!invert) {
82                    for (int i = 0; i < mTargets.size(); i++) {
83                        mTargets.get(i).setLayerType(View.LAYER_TYPE_NONE, null);
84                    }
85                }
86            }
87        });
88        animator.setDuration(mFadeDuration);
89        animator.setInterpolator(Interpolators.LINEAR_OUT_SLOW_IN);
90        animator.setStartDelay(delay);
91        animator.start();
92    }
93
94    public void update(boolean invert) {
95        if (invert) {
96            updateInvertPaint(1f);
97            for (int i = 0; i < mTargets.size(); i++) {
98                mTargets.get(i).setLayerType(View.LAYER_TYPE_HARDWARE, mDarkPaint);
99            }
100        } else {
101            for (int i = 0; i < mTargets.size(); i++) {
102                mTargets.get(i).setLayerType(View.LAYER_TYPE_NONE, null);
103            }
104        }
105    }
106
107    private void updateInvertPaint(float intensity) {
108        float components = 1 - 2 * intensity;
109        final float[] invert = {
110                components, 0f,         0f,         0f, 255f * intensity,
111                0f,         components, 0f,         0f, 255f * intensity,
112                0f,         0f,         components, 0f, 255f * intensity,
113                0f,         0f,         0f,         1f, 0f
114        };
115        mMatrix.set(invert);
116        mGrayscaleMatrix.setSaturation(1 - intensity);
117        mMatrix.preConcat(mGrayscaleMatrix);
118        mDarkPaint.setColorFilter(new ColorMatrixColorFilter(mMatrix));
119    }
120
121    public void setInverted(boolean invert, boolean fade, long delay) {
122        if (fade) {
123            fade(invert, delay);
124        } else {
125            update(invert);
126        }
127    }
128}