/* * Copyright (C) 2013 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.transition; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.animation.ObjectAnimator; import android.util.Log; import android.view.View; import android.view.ViewGroup; /** * This transition tracks changes to the visibility of target views in the * start and end scenes and fades views in or out when they become visible * or non-visible. Visibility is determined by both the * {@link View#setVisibility(int)} state of the view as well as whether it * is parented in the current view hierarchy. * *

A Fade transition can be described in a resource file by using the * tag fade, along with the standard * attributes of {@link android.R.styleable#Fade} and * {@link android.R.styleable#Transition}.

*/ public class Fade extends Visibility { private static boolean DBG = Transition.DBG && false; private static final String LOG_TAG = "Fade"; private static final String PROPNAME_ALPHA = "android:fade:alpha"; private static final String PROPNAME_SCREEN_X = "android:fade:screenX"; private static final String PROPNAME_SCREEN_Y = "android:fade:screenY"; /** * Fading mode used in {@link #Fade(int)} to make the transition * operate on targets that are appearing. Maybe be combined with * {@link #OUT} to fade both in and out. */ public static final int IN = 0x1; /** * Fading mode used in {@link #Fade(int)} to make the transition * operate on targets that are disappearing. Maybe be combined with * {@link #IN} to fade both in and out. */ public static final int OUT = 0x2; private int mFadingMode; /** * Constructs a Fade transition that will fade targets in and out. */ public Fade() { this(IN | OUT); } /** * Constructs a Fade transition that will fade targets in * and/or out, according to the value of fadingMode. * * @param fadingMode The behavior of this transition, a combination of * {@link #IN} and {@link #OUT}. */ public Fade(int fadingMode) { mFadingMode = fadingMode; } /** * Utility method to handle creating and running the Animator. */ private Animator createAnimation(View view, float startAlpha, float endAlpha, AnimatorListenerAdapter listener) { if (startAlpha == endAlpha) { // run listener if we're noop'ing the animation, to get the end-state results now if (listener != null) { listener.onAnimationEnd(null); } return null; } final ObjectAnimator anim = ObjectAnimator.ofFloat(view, "alpha", startAlpha, endAlpha); if (DBG) { Log.d(LOG_TAG, "Created animator " + anim); } if (listener != null) { anim.addListener(listener); anim.addPauseListener(listener); } return anim; } private void captureValues(TransitionValues transitionValues) { float alpha = transitionValues.view.getAlpha(); transitionValues.values.put(PROPNAME_ALPHA, alpha); int[] loc = new int[2]; transitionValues.view.getLocationOnScreen(loc); transitionValues.values.put(PROPNAME_SCREEN_X, loc[0]); transitionValues.values.put(PROPNAME_SCREEN_Y, loc[1]); } @Override public void captureStartValues(TransitionValues transitionValues) { super.captureStartValues(transitionValues); captureValues(transitionValues); } @Override public void captureEndValues(TransitionValues transitionValues) { super.captureEndValues(transitionValues); } @Override public Animator createAnimator(ViewGroup sceneRoot, TransitionValues startValues, TransitionValues endValues) { Animator animator = super.createAnimator(sceneRoot, startValues, endValues); if (animator == null && startValues != null && endValues != null) { boolean endVisible = isVisible(endValues); final View endView = endValues.view; float endAlpha = endView.getAlpha(); float startAlpha = (Float) startValues.values.get(PROPNAME_ALPHA); if ((endVisible && startAlpha < endAlpha && (mFadingMode & Fade.IN) != 0) || (!endVisible && startAlpha > endAlpha && (mFadingMode & Fade.OUT) != 0)) { animator = createAnimation(endView, startAlpha, endAlpha, null); } } return animator; } @Override public Animator onAppear(ViewGroup sceneRoot, TransitionValues startValues, int startVisibility, TransitionValues endValues, int endVisibility) { if ((mFadingMode & IN) != IN || endValues == null) { return null; } final View endView = endValues.view; if (DBG) { View startView = (startValues != null) ? startValues.view : null; Log.d(LOG_TAG, "Fade.onAppear: startView, startVis, endView, endVis = " + startView + ", " + startVisibility + ", " + endView + ", " + endVisibility); } // if alpha < 1, just fade it in from the current value if (endView.getAlpha() == 1.0f) { endView.setAlpha(0); TransitionListener transitionListener = new TransitionListenerAdapter() { boolean mCanceled = false; float mPausedAlpha; @Override public void onTransitionCancel(Transition transition) { endView.setAlpha(1); mCanceled = true; } @Override public void onTransitionEnd(Transition transition) { if (!mCanceled) { endView.setAlpha(1); } } @Override public void onTransitionPause(Transition transition) { mPausedAlpha = endView.getAlpha(); endView.setAlpha(1); } @Override public void onTransitionResume(Transition transition) { endView.setAlpha(mPausedAlpha); } }; addListener(transitionListener); } return createAnimation(endView, endView.getAlpha(), 1, null); } @Override public Animator onDisappear(ViewGroup sceneRoot, TransitionValues startValues, int startVisibility, TransitionValues endValues, int endVisibility) { if ((mFadingMode & OUT) != OUT) { return null; } View view; View startView = (startValues != null) ? startValues.view : null; View endView = (endValues != null) ? endValues.view : null; if (DBG) { Log.d(LOG_TAG, "Fade.onDisappear: startView, startVis, endView, endVis = " + startView + ", " + startVisibility + ", " + endView + ", " + endVisibility); } View overlayView = null; View viewToKeep = null; if (endView == null || endView.getParent() == null) { // view was removed: add the start view to the Overlay view = startView; overlayView = view; } else { // visibility change if (endVisibility == View.INVISIBLE) { view = endView; viewToKeep = view; } else { // Becoming GONE if (startView == endView) { view = endView; viewToKeep = view; } else { view = startView; overlayView = view; } } } final int finalVisibility = endVisibility; // TODO: add automatic facility to Visibility superclass for keeping views around if (overlayView != null) { // TODO: Need to do this for general case of adding to overlay int screenX = (Integer) startValues.values.get(PROPNAME_SCREEN_X); int screenY = (Integer) startValues.values.get(PROPNAME_SCREEN_Y); int[] loc = new int[2]; sceneRoot.getLocationOnScreen(loc); overlayView.offsetLeftAndRight((screenX - loc[0]) - overlayView.getLeft()); overlayView.offsetTopAndBottom((screenY - loc[1]) - overlayView.getTop()); sceneRoot.getOverlay().add(overlayView); // TODO: add automatic facility to Visibility superclass for keeping views around final float startAlpha = view.getAlpha(); float endAlpha = 0; final View finalView = view; final View finalOverlayView = overlayView; final View finalViewToKeep = viewToKeep; final ViewGroup finalSceneRoot = sceneRoot; final AnimatorListenerAdapter endListener = new AnimatorListenerAdapter() { @Override public void onAnimationEnd(Animator animation) { finalView.setAlpha(startAlpha); // TODO: restore view offset from overlay repositioning if (finalViewToKeep != null) { finalViewToKeep.setVisibility(finalVisibility); } if (finalOverlayView != null) { finalSceneRoot.getOverlay().remove(finalOverlayView); } } @Override public void onAnimationPause(Animator animation) { if (finalOverlayView != null) { finalSceneRoot.getOverlay().remove(finalOverlayView); } } @Override public void onAnimationResume(Animator animation) { if (finalOverlayView != null) { finalSceneRoot.getOverlay().add(finalOverlayView); } } }; return createAnimation(view, startAlpha, endAlpha, endListener); } if (viewToKeep != null) { // TODO: find a different way to do this, like just changing the view to be // VISIBLE for the duration of the transition viewToKeep.setVisibility((View.VISIBLE)); // TODO: add automatic facility to Visibility superclass for keeping views around final float startAlpha = view.getAlpha(); float endAlpha = 0; final View finalView = view; final View finalOverlayView = overlayView; final View finalViewToKeep = viewToKeep; final ViewGroup finalSceneRoot = sceneRoot; final AnimatorListenerAdapter endListener = new AnimatorListenerAdapter() { boolean mCanceled = false; float mPausedAlpha = -1; @Override public void onAnimationPause(Animator animation) { if (finalViewToKeep != null && !mCanceled) { finalViewToKeep.setVisibility(finalVisibility); } mPausedAlpha = finalView.getAlpha(); finalView.setAlpha(startAlpha); } @Override public void onAnimationResume(Animator animation) { if (finalViewToKeep != null && !mCanceled) { finalViewToKeep.setVisibility(View.VISIBLE); } finalView.setAlpha(mPausedAlpha); } @Override public void onAnimationCancel(Animator animation) { mCanceled = true; if (mPausedAlpha >= 0) { finalView.setAlpha(mPausedAlpha); } } @Override public void onAnimationEnd(Animator animation) { if (!mCanceled) { finalView.setAlpha(startAlpha); } // TODO: restore view offset from overlay repositioning if (finalViewToKeep != null && !mCanceled) { finalViewToKeep.setVisibility(finalVisibility); } if (finalOverlayView != null) { finalSceneRoot.getOverlay().remove(finalOverlayView); } } }; return createAnimation(view, startAlpha, endAlpha, endListener); } return null; } }