1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5  * in compliance with the License. You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software distributed under the License
10  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11  * or implied. See the License for the specific language governing permissions and limitations under
12  * the License.
13  */
14 package androidx.leanback.widget;
15 
16 import android.app.Activity;
17 import android.os.Handler;
18 import android.text.TextUtils;
19 import android.util.Log;
20 
21 import androidx.core.app.ActivityCompat;
22 import androidx.core.view.ViewCompat;
23 import androidx.leanback.transition.TransitionHelper;
24 import androidx.leanback.transition.TransitionListener;
25 import androidx.leanback.widget.FullWidthDetailsOverviewRowPresenter.ViewHolder;
26 
27 import java.lang.ref.WeakReference;
28 
29 /**
30  * Helper class to assist delayed shared element activity transition for view created by
31  * {@link FullWidthDetailsOverviewRowPresenter}. User must call
32  * {@link #setSharedElementEnterTransition(Activity, String, long)} during activity onCreate() and
33  * call {@link FullWidthDetailsOverviewRowPresenter#setListener(FullWidthDetailsOverviewRowPresenter.Listener)}.
34  * The helper implements {@link FullWidthDetailsOverviewRowPresenter.Listener} and starts delayed
35  * activity transition once {@link FullWidthDetailsOverviewRowPresenter.Listener#onBindLogo(ViewHolder)}
36  * is called.
37  */
38 public class FullWidthDetailsOverviewSharedElementHelper extends
39         FullWidthDetailsOverviewRowPresenter.Listener {
40 
41     static final String TAG = "DetailsTransitionHelper";
42     static final boolean DEBUG = false;
43 
44     private static final long DEFAULT_TIMEOUT = 5000;
45 
46     static class TransitionTimeOutRunnable implements Runnable {
47         WeakReference<FullWidthDetailsOverviewSharedElementHelper> mHelperRef;
48 
TransitionTimeOutRunnable(FullWidthDetailsOverviewSharedElementHelper helper)49         TransitionTimeOutRunnable(FullWidthDetailsOverviewSharedElementHelper helper) {
50             mHelperRef = new WeakReference<FullWidthDetailsOverviewSharedElementHelper>(helper);
51         }
52 
53         @Override
run()54         public void run() {
55             FullWidthDetailsOverviewSharedElementHelper helper = mHelperRef.get();
56             if (helper == null) {
57                 return;
58             }
59             if (DEBUG) {
60                 Log.d(TAG, "timeout " + helper.mActivityToRunTransition);
61             }
62             helper.startPostponedEnterTransition();
63         }
64     }
65 
66     ViewHolder mViewHolder;
67     Activity mActivityToRunTransition;
68     private boolean mStartedPostpone;
69     String mSharedElementName;
70     private boolean mAutoStartSharedElementTransition = true;
71 
setSharedElementEnterTransition(Activity activity, String sharedElementName)72     public void setSharedElementEnterTransition(Activity activity, String sharedElementName) {
73         setSharedElementEnterTransition(activity, sharedElementName, DEFAULT_TIMEOUT);
74     }
75 
setSharedElementEnterTransition(Activity activity, String sharedElementName, long timeoutMs)76     public void setSharedElementEnterTransition(Activity activity, String sharedElementName,
77             long timeoutMs) {
78         if ((activity == null && !TextUtils.isEmpty(sharedElementName))
79                 || (activity != null && TextUtils.isEmpty(sharedElementName))) {
80             throw new IllegalArgumentException();
81         }
82         if (activity == mActivityToRunTransition
83                 && TextUtils.equals(sharedElementName, mSharedElementName)) {
84             return;
85         }
86         mActivityToRunTransition = activity;
87         mSharedElementName = sharedElementName;
88         if (DEBUG) {
89             Log.d(TAG, "postponeEnterTransition " + mActivityToRunTransition);
90         }
91         Object transition = TransitionHelper.getSharedElementEnterTransition(activity.getWindow());
92         setAutoStartSharedElementTransition(transition != null);
93         ActivityCompat.postponeEnterTransition(mActivityToRunTransition);
94         if (timeoutMs > 0) {
95             new Handler().postDelayed(new TransitionTimeOutRunnable(this), timeoutMs);
96         }
97     }
98 
99     /**
100      * Enable or disable auto startPostponedEnterTransition() when bound to logo. When it's
101      * disabled, app must call {@link #startPostponedEnterTransition()} to kick off
102      * windowEnterTransition. By default, it is disabled when there is no
103      * windowEnterSharedElementTransition set on the activity.
104      */
setAutoStartSharedElementTransition(boolean enabled)105     public void setAutoStartSharedElementTransition(boolean enabled) {
106         mAutoStartSharedElementTransition = enabled;
107     }
108 
109     /**
110      * Returns true if auto startPostponedEnterTransition() when bound to logo. When it's
111      * disabled, app must call {@link #startPostponedEnterTransition()} to kick off
112      * windowEnterTransition. By default, it is disabled when there is no
113      * windowEnterSharedElementTransition set on the activity.
114      */
getAutoStartSharedElementTransition()115     public boolean getAutoStartSharedElementTransition() {
116         return mAutoStartSharedElementTransition;
117     }
118 
119     @Override
onBindLogo(ViewHolder vh)120     public void onBindLogo(ViewHolder vh) {
121         if (DEBUG) {
122             Log.d(TAG, "onBindLogo, could start transition of " + mActivityToRunTransition);
123         }
124         mViewHolder = vh;
125         if (!mAutoStartSharedElementTransition) {
126             return;
127         }
128         if (mViewHolder != null) {
129             if (DEBUG) {
130                 Log.d(TAG, "rebind? clear transitionName on current viewHolder "
131                         + mViewHolder.getOverviewView());
132             }
133             ViewCompat.setTransitionName(mViewHolder.getLogoViewHolder().view, null);
134         }
135         // After we got a image drawable,  we can determine size of right panel.
136         // We want right panel to have fixed size so that the right panel don't change size
137         // when the overview is layout as a small bounds in transition.
138         mViewHolder.getDetailsDescriptionFrame().postOnAnimation(new Runnable() {
139             @Override
140             public void run() {
141                 if (DEBUG) {
142                     Log.d(TAG, "setTransitionName "+mViewHolder.getOverviewView());
143                 }
144                 ViewCompat.setTransitionName(mViewHolder.getLogoViewHolder().view,
145                         mSharedElementName);
146                 Object transition = TransitionHelper.getSharedElementEnterTransition(
147                         mActivityToRunTransition.getWindow());
148                 if (transition != null) {
149                     TransitionHelper.addTransitionListener(transition, new TransitionListener() {
150                         @Override
151                         public void onTransitionEnd(Object transition) {
152                             if (DEBUG) {
153                                 Log.d(TAG, "onTransitionEnd " + mActivityToRunTransition);
154                             }
155                             // after transition if the action row still focused, transfer
156                             // focus to its children
157                             if (mViewHolder.getActionsRow().isFocused()) {
158                                 mViewHolder.getActionsRow().requestFocus();
159                             }
160                             TransitionHelper.removeTransitionListener(transition, this);
161                         }
162                     });
163                 }
164                 startPostponedEnterTransitionInternal();
165             }
166         });
167     }
168 
169     /**
170      * Manually start postponed enter transition.
171      */
startPostponedEnterTransition()172     public void startPostponedEnterTransition() {
173         new Handler().post(new Runnable(){
174             @Override
175             public void run() {
176                 startPostponedEnterTransitionInternal();
177             }
178         });
179     }
180 
startPostponedEnterTransitionInternal()181     void startPostponedEnterTransitionInternal() {
182         if (!mStartedPostpone && mViewHolder != null) {
183             if (DEBUG) {
184                 Log.d(TAG, "startPostponedEnterTransition " + mActivityToRunTransition);
185             }
186             ActivityCompat.startPostponedEnterTransition(mActivityToRunTransition);
187             mStartedPostpone = true;
188         }
189     }
190 }
191