| /* |
| * 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.content.Context; |
| import android.content.res.TypedArray; |
| import android.util.AttributeSet; |
| import android.util.Log; |
| import android.view.View; |
| import android.view.ViewGroup; |
| |
| import com.android.internal.R; |
| |
| /** |
| * 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. |
| * |
| * <p>The ability of this transition to fade out a particular view, and the |
| * way that that fading operation takes place, is based on |
| * the situation of the view in the view hierarchy. For example, if a view was |
| * simply removed from its parent, then the view will be added into a {@link |
| * android.view.ViewGroupOverlay} while fading. If a visible view is |
| * changed to be {@link View#GONE} or {@link View#INVISIBLE}, then the |
| * visibility will be changed to {@link View#VISIBLE} for the duration of |
| * the animation. However, if a view is in a hierarchy which is also altering |
| * its visibility, the situation can be more complicated. In general, if a |
| * view that is no longer in the hierarchy in the end scene still has a |
| * parent (so its parent hierarchy was removed, but it was not removed from |
| * its parent), then it will be left alone to avoid side-effects from |
| * improperly removing it from its parent. The only exception to this is if |
| * the previous {@link Scene} was |
| * {@link Scene#getSceneForLayout(android.view.ViewGroup, int, android.content.Context) |
| * created from a layout resource file}, then it is considered safe to un-parent |
| * the starting scene view in order to fade it out.</p> |
| * |
| * <p>A Fade transition can be described in a resource file by using the |
| * tag <code>fade</code>, along with the standard |
| * attributes of {@link android.R.styleable#Fade} and |
| * {@link android.R.styleable#Transition}.</p> |
| */ |
| public class Fade extends Visibility { |
| static final String PROPNAME_TRANSITION_ALPHA = "android:fade:transitionAlpha"; |
| |
| private static boolean DBG = Transition.DBG && false; |
| |
| private static final String LOG_TAG = "Fade"; |
| |
| /** |
| * 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. Equivalent to |
| * {@link Visibility#MODE_IN}. |
| */ |
| public static final int IN = Visibility.MODE_IN; |
| |
| /** |
| * 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. Equivalent to |
| * {@link Visibility#MODE_OUT}. |
| */ |
| public static final int OUT = Visibility.MODE_OUT; |
| |
| /** |
| * Constructs a Fade transition that will fade targets in and out. |
| */ |
| public Fade() { |
| } |
| |
| /** |
| * 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) { |
| setMode(fadingMode); |
| } |
| |
| public Fade(Context context, AttributeSet attrs) { |
| super(context, attrs); |
| TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.Fade); |
| int fadingMode = a.getInt(R.styleable.Fade_fadingMode, getMode()); |
| setMode(fadingMode); |
| } |
| |
| @Override |
| public void captureStartValues(TransitionValues transitionValues) { |
| super.captureStartValues(transitionValues); |
| transitionValues.values.put(PROPNAME_TRANSITION_ALPHA, |
| transitionValues.view.getTransitionAlpha()); |
| } |
| |
| /** |
| * Utility method to handle creating and running the Animator. |
| */ |
| private Animator createAnimation(final View view, float startAlpha, final float endAlpha) { |
| if (startAlpha == endAlpha) { |
| return null; |
| } |
| view.setTransitionAlpha(startAlpha); |
| final ObjectAnimator anim = ObjectAnimator.ofFloat(view, "transitionAlpha", endAlpha); |
| if (DBG) { |
| Log.d(LOG_TAG, "Created animator " + anim); |
| } |
| final FadeAnimatorListener listener = new FadeAnimatorListener(view); |
| anim.addListener(listener); |
| addListener(new TransitionListenerAdapter() { |
| @Override |
| public void onTransitionEnd(Transition transition) { |
| view.setTransitionAlpha(1); |
| transition.removeListener(this); |
| } |
| }); |
| return anim; |
| } |
| |
| @Override |
| public Animator onAppear(ViewGroup sceneRoot, View view, |
| TransitionValues startValues, |
| TransitionValues endValues) { |
| if (DBG) { |
| View startView = (startValues != null) ? startValues.view : null; |
| Log.d(LOG_TAG, "Fade.onAppear: startView, startVis, endView, endVis = " + |
| startView + ", " + view); |
| } |
| float startAlpha = getStartAlpha(startValues, 0); |
| if (startAlpha == 1) { |
| startAlpha = 0; |
| } |
| return createAnimation(view, startAlpha, 1); |
| } |
| |
| @Override |
| public Animator onDisappear(ViewGroup sceneRoot, final View view, TransitionValues startValues, |
| TransitionValues endValues) { |
| float startAlpha = getStartAlpha(startValues, 1); |
| return createAnimation(view, startAlpha, 0); |
| } |
| |
| private static float getStartAlpha(TransitionValues startValues, float fallbackValue) { |
| float startAlpha = fallbackValue; |
| if (startValues != null) { |
| Float startAlphaFloat = (Float) startValues.values.get(PROPNAME_TRANSITION_ALPHA); |
| if (startAlphaFloat != null) { |
| startAlpha = startAlphaFloat; |
| } |
| } |
| return startAlpha; |
| } |
| |
| private static class FadeAnimatorListener extends AnimatorListenerAdapter { |
| private final View mView; |
| private boolean mLayerTypeChanged = false; |
| |
| public FadeAnimatorListener(View view) { |
| mView = view; |
| } |
| |
| @Override |
| public void onAnimationStart(Animator animator) { |
| if (mView.hasOverlappingRendering() && mView.getLayerType() == View.LAYER_TYPE_NONE) { |
| mLayerTypeChanged = true; |
| mView.setLayerType(View.LAYER_TYPE_HARDWARE, null); |
| } |
| } |
| |
| @Override |
| public void onAnimationEnd(Animator animator) { |
| mView.setTransitionAlpha(1); |
| if (mLayerTypeChanged) { |
| mView.setLayerType(View.LAYER_TYPE_NONE, null); |
| } |
| } |
| } |
| } |