1/*
2 * Copyright (C) 2015 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 android.support.design.widget;
18
19import android.util.StateSet;
20
21import java.util.ArrayList;
22
23final class StateListAnimator {
24
25    private final ArrayList<Tuple> mTuples = new ArrayList<>();
26
27    private Tuple mLastMatch = null;
28    ValueAnimatorCompat mRunningAnimator = null;
29
30    private final ValueAnimatorCompat.AnimatorListener mAnimationListener
31            = new ValueAnimatorCompat.AnimatorListenerAdapter() {
32        @Override
33        public void onAnimationEnd(ValueAnimatorCompat animator) {
34            if (mRunningAnimator == animator) {
35                mRunningAnimator = null;
36            }
37        }
38    };
39
40    /**
41     * Associates the given Animation with the provided drawable state specs so that it will be run
42     * when the View's drawable state matches the specs.
43     *
44     * @param specs    The drawable state specs to match against
45     * @param animator The animator to run when the specs match
46     */
47    public void addState(int[] specs, ValueAnimatorCompat animator) {
48        Tuple tuple = new Tuple(specs, animator);
49        animator.addListener(mAnimationListener);
50        mTuples.add(tuple);
51    }
52
53    /**
54     * Called by View
55     */
56    void setState(int[] state) {
57        Tuple match = null;
58        final int count = mTuples.size();
59        for (int i = 0; i < count; i++) {
60            final Tuple tuple = mTuples.get(i);
61            if (StateSet.stateSetMatches(tuple.mSpecs, state)) {
62                match = tuple;
63                break;
64            }
65        }
66        if (match == mLastMatch) {
67            return;
68        }
69        if (mLastMatch != null) {
70            cancel();
71        }
72
73        mLastMatch = match;
74
75        if (match != null) {
76            start(match);
77        }
78    }
79
80    private void start(Tuple match) {
81        mRunningAnimator = match.mAnimator;
82        mRunningAnimator.start();
83    }
84
85    private void cancel() {
86        if (mRunningAnimator != null) {
87            mRunningAnimator.cancel();
88            mRunningAnimator = null;
89        }
90    }
91
92    /**
93     * If there is an animation running for a recent state change, ends it.
94     *
95     * <p>This causes the animation to assign the end value(s) to the View.</p>
96     */
97    public void jumpToCurrentState() {
98        if (mRunningAnimator != null) {
99            mRunningAnimator.end();
100            mRunningAnimator = null;
101        }
102    }
103
104    static class Tuple {
105        final int[] mSpecs;
106        final ValueAnimatorCompat mAnimator;
107
108        Tuple(int[] specs, ValueAnimatorCompat animator) {
109            mSpecs = specs;
110            mAnimator = animator;
111        }
112    }
113}