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; 20import android.view.View; 21import android.view.animation.Animation; 22 23import java.lang.ref.WeakReference; 24import java.util.ArrayList; 25 26final class StateListAnimator { 27 28 private final ArrayList<Tuple> mTuples = new ArrayList<>(); 29 30 private Tuple mLastMatch = null; 31 private Animation mRunningAnimation = null; 32 private WeakReference<View> mViewRef; 33 34 private Animation.AnimationListener mAnimationListener = new Animation.AnimationListener() { 35 @Override 36 public void onAnimationEnd(Animation animation) { 37 if (mRunningAnimation == animation) { 38 mRunningAnimation = null; 39 } 40 } 41 42 @Override 43 public void onAnimationStart(Animation animation) { 44 // no-op 45 } 46 47 @Override 48 public void onAnimationRepeat(Animation animation) { 49 // no-op 50 } 51 }; 52 53 /** 54 * Associates the given Animation with the provided drawable state specs so that it will be run 55 * when the View's drawable state matches the specs. 56 * 57 * @param specs The drawable state specs to match against 58 * @param animation The Animation to run when the specs match 59 */ 60 public void addState(int[] specs, Animation animation) { 61 Tuple tuple = new Tuple(specs, animation); 62 animation.setAnimationListener(mAnimationListener); 63 mTuples.add(tuple); 64 } 65 66 /** 67 * Returns the current {@link Animation} which is started because of a state 68 * change. 69 * 70 * @return The currently running Animation or null if no Animation is running 71 */ 72 Animation getRunningAnimation() { 73 return mRunningAnimation; 74 } 75 76 77 View getTarget() { 78 return mViewRef == null ? null : mViewRef.get(); 79 } 80 81 void setTarget(View view) { 82 final View current = getTarget(); 83 if (current == view) { 84 return; 85 } 86 if (current != null) { 87 clearTarget(); 88 } 89 if (view != null) { 90 mViewRef = new WeakReference<>(view); 91 } 92 } 93 94 private void clearTarget() { 95 final View view = getTarget(); 96 final int size = mTuples.size(); 97 for (int i = 0; i < size; i++) { 98 Animation anim = mTuples.get(i).mAnimation; 99 if (view.getAnimation() == anim) { 100 view.clearAnimation(); 101 } 102 } 103 mViewRef = null; 104 mLastMatch = null; 105 mRunningAnimation = null; 106 } 107 108 /** 109 * Called by View 110 */ 111 void setState(int[] state) { 112 Tuple match = null; 113 final int count = mTuples.size(); 114 for (int i = 0; i < count; i++) { 115 final Tuple tuple = mTuples.get(i); 116 if (StateSet.stateSetMatches(tuple.mSpecs, state)) { 117 match = tuple; 118 break; 119 } 120 } 121 if (match == mLastMatch) { 122 return; 123 } 124 if (mLastMatch != null) { 125 cancel(); 126 } 127 128 mLastMatch = match; 129 130 View view = mViewRef.get(); 131 if (match != null && view != null && view.getVisibility() == View.VISIBLE ) { 132 start(match); 133 } 134 } 135 136 private void start(Tuple match) { 137 mRunningAnimation = match.mAnimation; 138 139 View view = getTarget(); 140 if (view != null) { 141 view.startAnimation(mRunningAnimation); 142 } 143 } 144 145 private void cancel() { 146 if (mRunningAnimation != null) { 147 final View view = getTarget(); 148 if (view != null && view.getAnimation() == mRunningAnimation) { 149 view.clearAnimation(); 150 } 151 mRunningAnimation = null; 152 } 153 } 154 155 /** 156 * @hide 157 */ 158 ArrayList<Tuple> getTuples() { 159 return mTuples; 160 } 161 162 /** 163 * If there is an animation running for a recent state change, ends it. <p> This causes the 164 * animation to assign the end value(s) to the View. 165 */ 166 public void jumpToCurrentState() { 167 if (mRunningAnimation != null) { 168 final View view = getTarget(); 169 if (view != null && view.getAnimation() == mRunningAnimation) { 170 view.clearAnimation(); 171 } 172 } 173 } 174 175 static class Tuple { 176 final int[] mSpecs; 177 final Animation mAnimation; 178 179 private Tuple(int[] specs, Animation Animation) { 180 mSpecs = specs; 181 mAnimation = Animation; 182 } 183 184 int[] getSpecs() { 185 return mSpecs; 186 } 187 188 Animation getAnimation() { 189 return mAnimation; 190 } 191 } 192}