1/*
2 * Copyright (C) 2016 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.statusbar;
18
19import android.view.View;
20
21import com.android.systemui.Interpolators;
22import com.android.systemui.statusbar.stack.StackStateAnimator;
23
24/**
25 * A helper to fade views in and out.
26 */
27public class CrossFadeHelper {
28    public static final long ANIMATION_DURATION_LENGTH = 210;
29
30    public static void fadeOut(final View view, final Runnable endRunnable) {
31        fadeOut(view, ANIMATION_DURATION_LENGTH, 0, endRunnable);
32    }
33
34    public static void fadeOut(final View view, long duration, int delay,
35            final Runnable endRunnable) {
36        view.animate().cancel();
37        view.animate()
38                .alpha(0f)
39                .setDuration(duration)
40                .setInterpolator(Interpolators.ALPHA_OUT)
41                .setStartDelay(delay)
42                .withEndAction(new Runnable() {
43                    @Override
44                    public void run() {
45                        if (endRunnable != null) {
46                            endRunnable.run();
47                        }
48                        view.setVisibility(View.INVISIBLE);
49                    }
50                });
51        if (view.hasOverlappingRendering()) {
52            view.animate().withLayer();
53        }
54    }
55
56    public static void fadeOut(View view, float fadeOutAmount) {
57        fadeOut(view, fadeOutAmount, true /* remap */);
58    }
59
60    /**
61     * Fade out a view by a given progress amount
62     * @param view the view to fade out
63     * @param fadeOutAmount how much the view is faded out. 0 means not at all and 1 means fully
64     *                      faded out
65     * @param remap whether the fade amount should be remapped to the shorter duration
66     * {@link #ANIMATION_DURATION_LENGTH} from the normal fade duration
67     * {@link StackStateAnimator#ANIMATION_DURATION_STANDARD} in order to have a faster fading.
68     *
69     * @see #fadeIn(View, float, boolean)
70     */
71    public static void fadeOut(View view, float fadeOutAmount, boolean remap) {
72        view.animate().cancel();
73        if (fadeOutAmount == 1.0f) {
74            view.setVisibility(View.INVISIBLE);
75        } else if (view.getVisibility() == View.INVISIBLE) {
76            view.setVisibility(View.VISIBLE);
77        }
78        if (remap) {
79            fadeOutAmount = mapToFadeDuration(fadeOutAmount);
80        }
81        float alpha = Interpolators.ALPHA_OUT.getInterpolation(1.0f - fadeOutAmount);
82        view.setAlpha(alpha);
83        updateLayerType(view, alpha);
84    }
85
86    private static float mapToFadeDuration(float fadeOutAmount) {
87        // Assuming a linear interpolator, we can easily map it to our new duration
88        float endPoint = (float) ANIMATION_DURATION_LENGTH
89                / (float) StackStateAnimator.ANIMATION_DURATION_STANDARD;
90        return Math.min(fadeOutAmount / endPoint, 1.0f);
91    }
92
93    private static void updateLayerType(View view, float alpha) {
94        if (view.hasOverlappingRendering() && alpha > 0.0f && alpha < 1.0f) {
95            view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
96        } else if (view.getLayerType() == View.LAYER_TYPE_HARDWARE) {
97            view.setLayerType(View.LAYER_TYPE_NONE, null);
98        }
99    }
100
101    public static void fadeIn(final View view) {
102        fadeIn(view, ANIMATION_DURATION_LENGTH, 0);
103    }
104
105    public static void fadeIn(final View view, long duration, int delay) {
106        view.animate().cancel();
107        if (view.getVisibility() == View.INVISIBLE) {
108            view.setAlpha(0.0f);
109            view.setVisibility(View.VISIBLE);
110        }
111        view.animate()
112                .alpha(1f)
113                .setDuration(duration)
114                .setStartDelay(delay)
115                .setInterpolator(Interpolators.ALPHA_IN)
116                .withEndAction(null);
117        if (view.hasOverlappingRendering()) {
118            view.animate().withLayer();
119        }
120    }
121
122    public static void fadeIn(View view, float fadeInAmount) {
123        fadeIn(view, fadeInAmount, true /* remap */);
124    }
125
126    /**
127     * Fade in a view by a given progress amount
128     * @param view the view to fade in
129     * @param fadeInAmount how much the view is faded in. 0 means not at all and 1 means fully
130     *                     faded in.
131     * @param remap whether the fade amount should be remapped to the shorter duration
132     * {@link #ANIMATION_DURATION_LENGTH} from the normal fade duration
133     * {@link StackStateAnimator#ANIMATION_DURATION_STANDARD} in order to have a faster fading.
134     *
135     * @see #fadeOut(View, float, boolean)
136     */
137    public static void fadeIn(View view, float fadeInAmount, boolean remap) {
138        view.animate().cancel();
139        if (view.getVisibility() == View.INVISIBLE) {
140            view.setVisibility(View.VISIBLE);
141        }
142        if (remap) {
143            fadeInAmount = mapToFadeDuration(fadeInAmount);
144        }
145        float alpha = Interpolators.ALPHA_IN.getInterpolation(fadeInAmount);
146        view.setAlpha(alpha);
147        updateLayerType(view, alpha);
148    }
149}
150