ActivityTransitionState.java revision 1fecfb2ddcdf4335ff543bdd549b8e4d36139da8 
1/*
2 * Copyright (C) 2014 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 */
16package android.app;
17
18import android.os.Bundle;
19import android.os.ResultReceiver;
20import android.util.ArrayMap;
21import android.util.SparseArray;
22import android.view.View;
23import android.view.Window;
24
25import java.lang.ref.WeakReference;
26import java.util.ArrayList;
27
28/**
29 * This class contains all persistence-related functionality for Activity Transitions.
30 * Activities start exit and enter Activity Transitions through this class.
31 */
32class ActivityTransitionState {
33
34    private static final String ENTERING_SHARED_ELEMENTS = "android:enteringSharedElements";
35
36    private static final String EXITING_MAPPED_FROM = "android:exitingMappedFrom";
37
38    private static final String EXITING_MAPPED_TO = "android:exitingMappedTo";
39
40    /**
41     * The shared elements that the calling Activity has said that they transferred to this
42     * Activity.
43     */
44    private ArrayList<String> mEnteringNames;
45
46    /**
47     * The names of shared elements that were shared to the called Activity.
48     */
49    private ArrayList<String> mExitingFrom;
50
51    /**
52     * The names of local Views that were shared out, mapped to those elements in mExitingFrom.
53     */
54    private ArrayList<String> mExitingTo;
55
56    /**
57     * The local Views that were shared out, mapped to those elements in mExitingFrom.
58     */
59    private ArrayList<View> mExitingToView;
60
61    /**
62     * The ExitTransitionCoordinator used to start an Activity. Used to make the elements restore
63     * Visibility of exited Views.
64     */
65    private ExitTransitionCoordinator mCalledExitCoordinator;
66
67    /**
68     * We must be able to cancel entering transitions to stop changing the Window to
69     * opaque when we exit before making the Window opaque.
70     */
71    private EnterTransitionCoordinator mEnterTransitionCoordinator;
72
73    /**
74     * ActivityOptions used on entering this Activity.
75     */
76    private ActivityOptions mEnterActivityOptions;
77
78    /**
79     * Has an exit transition been started? If so, we don't want to double-exit.
80     */
81    private boolean mHasExited;
82
83    /**
84     * Postpone painting and starting the enter transition until this is false.
85     */
86    private boolean mIsEnterPostponed;
87
88    /**
89     * Potential exit transition coordinators.
90     */
91    private SparseArray<WeakReference<ExitTransitionCoordinator>> mExitTransitionCoordinators;
92
93    /**
94     * Next key for mExitTransitionCoordinator.
95     */
96    private int mExitTransitionCoordinatorsKey = 1;
97
98    public ActivityTransitionState() {
99    }
100
101    public int addExitTransitionCoordinator(ExitTransitionCoordinator exitTransitionCoordinator) {
102        if (mExitTransitionCoordinators == null) {
103            mExitTransitionCoordinators =
104                    new SparseArray<WeakReference<ExitTransitionCoordinator>>();
105        }
106        WeakReference<ExitTransitionCoordinator> ref = new WeakReference(exitTransitionCoordinator);
107        // clean up old references:
108        for (int i = mExitTransitionCoordinators.size() - 1; i >= 0; i--) {
109            WeakReference<ExitTransitionCoordinator> oldRef
110                    = mExitTransitionCoordinators.valueAt(i);
111            if (oldRef.get() == null) {
112                mExitTransitionCoordinators.removeAt(i);
113            }
114        }
115        int newKey = mExitTransitionCoordinatorsKey++;
116        mExitTransitionCoordinators.append(newKey, ref);
117        return newKey;
118    }
119
120    public void readState(Bundle bundle) {
121        if (bundle != null) {
122            if (mEnterTransitionCoordinator == null || mEnterTransitionCoordinator.isReturning()) {
123                mEnteringNames = bundle.getStringArrayList(ENTERING_SHARED_ELEMENTS);
124            }
125            if (mEnterTransitionCoordinator == null) {
126                mExitingFrom = bundle.getStringArrayList(EXITING_MAPPED_FROM);
127                mExitingTo = bundle.getStringArrayList(EXITING_MAPPED_TO);
128            }
129        }
130    }
131
132    public void saveState(Bundle bundle) {
133        if (mEnteringNames != null) {
134            bundle.putStringArrayList(ENTERING_SHARED_ELEMENTS, mEnteringNames);
135        }
136        if (mExitingFrom != null) {
137            bundle.putStringArrayList(EXITING_MAPPED_FROM, mExitingFrom);
138            bundle.putStringArrayList(EXITING_MAPPED_TO, mExitingTo);
139        }
140    }
141
142    public void setEnterActivityOptions(Activity activity, ActivityOptions options) {
143        if (activity.getWindow().hasFeature(Window.FEATURE_CONTENT_TRANSITIONS)
144                && options != null && mEnterActivityOptions == null
145                && options.getAnimationType() == ActivityOptions.ANIM_SCENE_TRANSITION) {
146            mEnterActivityOptions = options;
147            if (mEnterActivityOptions.isReturning()) {
148                int result = mEnterActivityOptions.getResultCode();
149                if (result != 0) {
150                    activity.onActivityReenter(result, mEnterActivityOptions.getResultData());
151                }
152            }
153        }
154    }
155
156    public void enterReady(Activity activity) {
157        if (mEnterActivityOptions == null) {
158            return;
159        }
160        mHasExited = false;
161        ArrayList<String> sharedElementNames = mEnterActivityOptions.getSharedElementNames();
162        ResultReceiver resultReceiver = mEnterActivityOptions.getResultReceiver();
163        if (mEnterActivityOptions.isReturning()) {
164            restoreExitedViews();
165            activity.getWindow().getDecorView().setVisibility(View.VISIBLE);
166        }
167        mEnterTransitionCoordinator = new EnterTransitionCoordinator(activity,
168                resultReceiver, sharedElementNames, mEnterActivityOptions.isReturning());
169
170        if (!mIsEnterPostponed) {
171            startEnter();
172        }
173    }
174
175    public void postponeEnterTransition() {
176        mIsEnterPostponed = true;
177    }
178
179    public void startPostponedEnterTransition() {
180        if (mIsEnterPostponed) {
181            mIsEnterPostponed = false;
182            if (mEnterTransitionCoordinator != null) {
183                startEnter();
184            }
185        }
186    }
187
188    private void startEnter() {
189        if (mEnterActivityOptions.isReturning()) {
190            if (mExitingToView != null) {
191                mEnterTransitionCoordinator.viewInstancesReady(mExitingFrom, mExitingToView);
192            } else {
193                mEnterTransitionCoordinator.namedViewsReady(mExitingFrom, mExitingTo);
194            }
195        } else {
196            mEnterTransitionCoordinator.namedViewsReady(null, null);
197            mEnteringNames = mEnterTransitionCoordinator.getAllSharedElementNames();
198        }
199
200        mExitingFrom = null;
201        mExitingTo = null;
202        mExitingToView = null;
203        mEnterActivityOptions = null;
204    }
205
206    public void onStop() {
207        restoreExitedViews();
208        if (mEnterTransitionCoordinator != null) {
209            mEnterTransitionCoordinator.stop();
210            mEnterTransitionCoordinator = null;
211        }
212    }
213
214    public void onResume() {
215        restoreExitedViews();
216    }
217
218    private void restoreExitedViews() {
219        if (mCalledExitCoordinator != null) {
220            mCalledExitCoordinator.resetViews();
221            mCalledExitCoordinator = null;
222        }
223    }
224
225    public boolean startExitBackTransition(Activity activity) {
226        if (mEnteringNames == null) {
227            return false;
228        } else {
229            if (!mHasExited) {
230                mHasExited = true;
231                if (mEnterTransitionCoordinator != null) {
232                    mEnterTransitionCoordinator.stop();
233                    mEnterTransitionCoordinator = null;
234                }
235                ArrayMap<String, View> sharedElements = new ArrayMap<String, View>();
236                activity.getWindow().getDecorView().findNamedViews(sharedElements);
237
238                ExitTransitionCoordinator exitCoordinator =
239                        new ExitTransitionCoordinator(activity, mEnteringNames, null, null, true);
240                exitCoordinator.startExit(activity.mResultCode, activity.mResultData);
241            }
242            return true;
243        }
244    }
245
246    public void startExitOutTransition(Activity activity, Bundle options) {
247        if (!activity.getWindow().hasFeature(Window.FEATURE_CONTENT_TRANSITIONS)) {
248            return;
249        }
250        ActivityOptions activityOptions = new ActivityOptions(options);
251        if (activityOptions.getAnimationType() == ActivityOptions.ANIM_SCENE_TRANSITION) {
252            int key = activityOptions.getExitCoordinatorKey();
253            int index = mExitTransitionCoordinators.indexOfKey(key);
254            if (index >= 0) {
255                mCalledExitCoordinator = mExitTransitionCoordinators.valueAt(index).get();
256                mExitTransitionCoordinators.removeAt(index);
257                if (mCalledExitCoordinator != null) {
258                    mExitingFrom = mCalledExitCoordinator.getAcceptedNames();
259                    mExitingTo = mCalledExitCoordinator.getMappedNames();
260                    mExitingToView = mCalledExitCoordinator.getMappedViews();
261                    mCalledExitCoordinator.startExit();
262                }
263            }
264        }
265    }
266}
267