1 /* 2 * Copyright (C) 2017 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 androidx.transition; 18 19 import android.animation.Animator; 20 import android.animation.TimeInterpolator; 21 import android.content.Context; 22 import android.graphics.Rect; 23 import android.util.AttributeSet; 24 import android.view.View; 25 import android.view.ViewGroup; 26 import android.view.animation.AccelerateInterpolator; 27 import android.view.animation.DecelerateInterpolator; 28 29 import androidx.annotation.NonNull; 30 31 /** 32 * This transition tracks changes to the visibility of target views in the 33 * start and end scenes and moves views in or out from the edges of the 34 * scene. Visibility is determined by both the 35 * {@link View#setVisibility(int)} state of the view as well as whether it 36 * is parented in the current view hierarchy. Disappearing Views are 37 * limited as described in {@link Visibility#onDisappear(android.view.ViewGroup, 38 * TransitionValues, int, TransitionValues, int)}. 39 * <p>Views move away from the focal View or the center of the Scene if 40 * no epicenter was provided.</p> 41 */ 42 public class Explode extends Visibility { 43 44 private static final TimeInterpolator sDecelerate = new DecelerateInterpolator(); 45 private static final TimeInterpolator sAccelerate = new AccelerateInterpolator(); 46 private static final String PROPNAME_SCREEN_BOUNDS = "android:explode:screenBounds"; 47 48 private int[] mTempLoc = new int[2]; 49 Explode()50 public Explode() { 51 setPropagation(new CircularPropagation()); 52 } 53 Explode(Context context, AttributeSet attrs)54 public Explode(Context context, AttributeSet attrs) { 55 super(context, attrs); 56 setPropagation(new CircularPropagation()); 57 } 58 captureValues(TransitionValues transitionValues)59 private void captureValues(TransitionValues transitionValues) { 60 View view = transitionValues.view; 61 view.getLocationOnScreen(mTempLoc); 62 int left = mTempLoc[0]; 63 int top = mTempLoc[1]; 64 int right = left + view.getWidth(); 65 int bottom = top + view.getHeight(); 66 transitionValues.values.put(PROPNAME_SCREEN_BOUNDS, new Rect(left, top, right, bottom)); 67 } 68 69 @Override captureStartValues(@onNull TransitionValues transitionValues)70 public void captureStartValues(@NonNull TransitionValues transitionValues) { 71 super.captureStartValues(transitionValues); 72 captureValues(transitionValues); 73 } 74 75 @Override captureEndValues(@onNull TransitionValues transitionValues)76 public void captureEndValues(@NonNull TransitionValues transitionValues) { 77 super.captureEndValues(transitionValues); 78 captureValues(transitionValues); 79 } 80 81 @Override onAppear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues)82 public Animator onAppear(ViewGroup sceneRoot, View view, 83 TransitionValues startValues, TransitionValues endValues) { 84 if (endValues == null) { 85 return null; 86 } 87 Rect bounds = (Rect) endValues.values.get(PROPNAME_SCREEN_BOUNDS); 88 float endX = view.getTranslationX(); 89 float endY = view.getTranslationY(); 90 calculateOut(sceneRoot, bounds, mTempLoc); 91 float startX = endX + mTempLoc[0]; 92 float startY = endY + mTempLoc[1]; 93 94 return TranslationAnimationCreator.createAnimation(view, endValues, bounds.left, bounds.top, 95 startX, startY, endX, endY, sDecelerate); 96 } 97 98 @Override onDisappear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues)99 public Animator onDisappear(ViewGroup sceneRoot, View view, 100 TransitionValues startValues, TransitionValues endValues) { 101 if (startValues == null) { 102 return null; 103 } 104 Rect bounds = (Rect) startValues.values.get(PROPNAME_SCREEN_BOUNDS); 105 int viewPosX = bounds.left; 106 int viewPosY = bounds.top; 107 float startX = view.getTranslationX(); 108 float startY = view.getTranslationY(); 109 float endX = startX; 110 float endY = startY; 111 int[] interruptedPosition = (int[]) startValues.view.getTag(R.id.transition_position); 112 if (interruptedPosition != null) { 113 // We want to have the end position relative to the interrupted position, not 114 // the position it was supposed to start at. 115 endX += interruptedPosition[0] - bounds.left; 116 endY += interruptedPosition[1] - bounds.top; 117 bounds.offsetTo(interruptedPosition[0], interruptedPosition[1]); 118 } 119 calculateOut(sceneRoot, bounds, mTempLoc); 120 endX += mTempLoc[0]; 121 endY += mTempLoc[1]; 122 123 return TranslationAnimationCreator.createAnimation(view, startValues, 124 viewPosX, viewPosY, startX, startY, endX, endY, sAccelerate); 125 } 126 calculateOut(View sceneRoot, Rect bounds, int[] outVector)127 private void calculateOut(View sceneRoot, Rect bounds, int[] outVector) { 128 sceneRoot.getLocationOnScreen(mTempLoc); 129 int sceneRootX = mTempLoc[0]; 130 int sceneRootY = mTempLoc[1]; 131 int focalX; 132 int focalY; 133 134 Rect epicenter = getEpicenter(); 135 if (epicenter == null) { 136 focalX = sceneRootX + (sceneRoot.getWidth() / 2) 137 + Math.round(sceneRoot.getTranslationX()); 138 focalY = sceneRootY + (sceneRoot.getHeight() / 2) 139 + Math.round(sceneRoot.getTranslationY()); 140 } else { 141 focalX = epicenter.centerX(); 142 focalY = epicenter.centerY(); 143 } 144 145 int centerX = bounds.centerX(); 146 int centerY = bounds.centerY(); 147 float xVector = centerX - focalX; 148 float yVector = centerY - focalY; 149 150 if (xVector == 0 && yVector == 0) { 151 // Random direction when View is centered on focal View. 152 xVector = (float) (Math.random() * 2) - 1; 153 yVector = (float) (Math.random() * 2) - 1; 154 } 155 float vectorSize = calculateDistance(xVector, yVector); 156 xVector /= vectorSize; 157 yVector /= vectorSize; 158 159 float maxDistance = 160 calculateMaxDistance(sceneRoot, focalX - sceneRootX, focalY - sceneRootY); 161 162 outVector[0] = Math.round(maxDistance * xVector); 163 outVector[1] = Math.round(maxDistance * yVector); 164 } 165 calculateMaxDistance(View sceneRoot, int focalX, int focalY)166 private static float calculateMaxDistance(View sceneRoot, int focalX, int focalY) { 167 int maxX = Math.max(focalX, sceneRoot.getWidth() - focalX); 168 int maxY = Math.max(focalY, sceneRoot.getHeight() - focalY); 169 return calculateDistance(maxX, maxY); 170 } 171 calculateDistance(float x, float y)172 private static float calculateDistance(float x, float y) { 173 return (float) Math.sqrt((x * x) + (y * y)); 174 } 175 176 } 177